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09.09.24 TAB Agenda 6 - Iris Ave CEAPCITY OF BOULDER TRANSPORTATION ADVISORY BOARD AGENDA ITEM MEETING DATE: September 9, 2024 AGENDA TITLE: Public hearing and consideration of a recommendation regarding the Iris Avenue Transportation Improvements Project Community and Environmental Assessment Process (CEAP) PRESENTERS: Valerie Watson, Interim Director of Transportation and Mobility Stephen Rijo, Transportation Planning Manager Gerrit Slatter, Principal Transportation Projects Engineer Devin Joslin, Principal Traffic Engineer Lindsay Merz, Civil Engineering Manager Melanie Sloan, Transportation Principal Project Manager Daniel Sheeter, Transportation Principal Planner EXECUTIVE SUMMARY The purpose of the Iris Avenue Transportation Improvements Project is to make Iris Avenue between Broadway and 28th Street safer, more comfortable, and connected. The project will address the actions of the Vision Zero Action Plan by implementing proven safety countermeasures on this priority Core Arterial Network (CAN) corridor that is also on the High Risk Network (HRN). The HRN is a small percentage (7%) of city streets that have nearly half of all fatal and serious injury crashes in the city. The CAN is a connected system of protected bicycle lanes, intersection enhancements, pedestrian facilities, and transit facility upgrades to create safe, comfortable connections along Boulder’s main corridors. Staff completed a Community Environmental Assessment Process (CEAP) that included robust community and stakeholder engagement, analysis of existing conditions data, consideration of policy and plan guidance, and evaluation of conceptual alternatives using a CEAP checklist and project specific evaluation criteria. The CEAP identified Alternative B as the recommended alternative because it best balances community priorities, plan and policy guidance, and issues identified by the existing conditions data which demonstrate the need for crash reduction, moderating vehicle speeds, providing bike and pedestrian safety and comfort and preserving existing public street trees. Alternative B can achieve these safety benefits with minimal added travel time and lower costs and time to implement than other conceptual design alternatives. 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 1 of 111 Alternative B reconfigures vehicle lanes between 13th Street and Folsom/26th Street from four to three, including a center turn lane, incorporates protected intersection elements, implements traffic signal changes to separate turning vehicles from people walking and biking at major intersections, makes spot improvements to existing sidewalks, and provides a two-way protected bike lane on the north side of the street. The center turn lane and two-way protected bike lane each provide dedicated space for emergency response during day-to-day and disaster scenarios respectively. Alternative B can be implemented within the existing curb-to-curb width and so preserves existing public street trees. It is estimated, based on recently completed similar projects, to cost about $5 million in today’s dollars to implement and take three to four times less time to implement than the two design alternatives that maintain the existing number of vehicle lanes. Traffic modeling completed for the project found these benefits can be achieved with a potential travel time increase ranging from 2 to 58 seconds for 95% of trips on the corridor, and the slowest trips with a maximum of 2 minutes and 9 seconds with Alternative B. Staff first introduced the project to TAB at its April 11, 2022 meeting, provided project updates at the October 10, 2022, July 10, 2023, and April 8, 2024 meetings. Since that last meeting, staff have completed the CEAP, identified a recommended alternative, and gathered public input on the evaluation and recommendation. The purpose of this item is for TAB to review the CEAP and the recommended conceptual design alternative and provide a recommendation to city council to inform the next stage of the project design process. BACKGROUND Iris Avenue, from 28th Street to Broadway, is an important east-west corridor in north Boulder that provides direct, convenient connections to everyday neighborhood destinations and supports travel within Boulder and between Boulder and communities along the Diagonal Highway (Figure 1). Iris Avenue’s role in the local and regional transportation network is important today – and will only become more important in the coming years as local and regional land use and transportation projects are completed. Figure 1: Iris Avenue Transportation Improvements Project Limits 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 2 of 111 However, Iris Avenue does not provide the safest, most comfortable connections regardless of how you travel. In 2019, the Transportation Master Plan and the Low Stress Walk and Bike Network Plan recommended greater separation and protection between vehicle and bicycle lanes on Iris Avenue and a need for pedestrian improvements in key areas due to the road having more than three vehicle lanes, the posted speed limit set at 35 miles per hour, and average daily traffic being greater than 6,000 vehicles. In 2022, the Safe Streets Report (SSR) found between 2018 and 2020, 14,500 people were involved in a crash in Boulder, resulting in 150 serious injuries. Sixty-seven percent of severe traffic crashes, those that result in serious injury or fatality, occur on arterial streets. The report found these severe injury crashes occurred at several intersections on Iris Ave: 28th Street, Folsom/26th Street, and Broadway. The SSR also identified Areas of Concern: crash types that disproportionately affect certain groups, like young people and seniors. Data from the Iris project revealed that one in ten pedestrians or cyclists traveling on or across Iris on an average day were young, elderly, or disabled. Community input shared a common sentiment: people feel unsafe walking or biking along and across Iris, yet hundreds do so every day. In response to the findings of the SSR, City Council, in partnership with the Transportation Advisory Board (TAB), elevated work on the Core Arterial Network (CAN) as one of its 10 priorities for city department efforts. Council reaffirmed CAN as a priority in April 2024. The CAN is the connected system of protected bicycle lanes, intersection enhancements, pedestrian facilities, and transit facility upgrades that will help reduce the potential for severe crashes and make it more comfortable and convenient for people to get where they need to go along Boulder’s main corridors, including Iris Avenue. In 2023, the 2023-2027 Vision Zero Action Plan (VZAP) identified specific actions and strategies to address the findings of the SSR. The High Risk Network (HRN) was developed as part of the plan as a way to focus actions on places where severe crashes occur or are more likely to occur in the future. The HRN has an outsized proportion of previous severe crash incidence: the HRN represents only 7% of the city’s street network but nearly half of all severe crashes occur on these streets. The HRN also identifies locations where more than five of the six most common risk factors for future crashes are present. Proactively managing risk and mitigating crashes on this small percentage of streets can have an outsized impact on reducing fatal and serious injury crashes citywide and achieve the greatest impact in the shortest amount of time. Iris Avenue, from 19th to 28th streets, is on the HRN. Two core strategies of the VZAP are to work on the CAN and the HRN. Action 3 of the plan commits the city to implement capital projects by 2027 to improve safety and comfort on priority CAN corridors that are also on the HRN, which includes Iris Avenue. The Iris Avenue Transportation Improvements project completed a CEAP to identify a recommended alternative that incorporates proven safety countermeasures with a focus on increasing mobility choices, improving safety for everyone, making walking, biking, scooting, and taking transit more attractive and convenient, and improving connections to local, citywide and regional destinations. 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 3 of 111 An update on the progress of the Iris Avenue project with detail on the conceptual design alternatives, project considerations, and community priorities was provided to City Council at a study session on June 27, 2024. ANALYSIS The recommended alternative is Alternative B: Two-Way Protected Bike Lane and No Change to Roadway Width (Figure 2). The CEAP evaluation supporting this recommendation can be found in Attachment A – Iris Avenue Transportation Improvements Project Community and Environmental Assessment Process (CEAP). Alternative B is recommended because it best balances community priorities, plan and policy guidance, and issues identified by the existing conditions data for crash reduction, moderating vehicle speeds, providing bike and pedestrian safety and comfort, and preserving existing public street trees, with minimal added travel time and lower costs and time to implement that other conceptual design alternatives. 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 4 of 111 Figure 2: Iris Avenue Project Recommended Design: Alternative B 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 5 of 111 Figure 3 Iris Alternatives Evaluation Results 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 6 of 111 Alternative B achieves these benefits by: • Reconfiguring the roadway with vehicle lane repurposing (between 13th Street and Folsom/26th Street) from four vehicle lanes to two vehicle lanes with a center turn lane, and moderates vehicle speeds and reduces the corridor’s common crash types: rear ends and approach turn crashes. o The center turn lane supports vehicles turning in and out of side streets and driveways by:  Removing turning vehicles from the vehicle travel lane, reducing the potential for rear rend crashes.  Giving drivers a safe place to wait for a gap in traffic to complete their turn, reducing the potential for approach turn crashes. o Existing conditions data, Federal Highway Administration guidance 1 and traffic modeling indicate three vehicle lanes provides sufficient capacity for the number of vehicles that use Iris Avenue today.  Traffic modeling utilized existing vehicle, bicycle and pedestrian volumes, an approach supported by the Boulder Valley Comprehensive Plan transportation and land use assumptions, 2023 Travel Diary Study findings of reduced single occupancy vehicle use and increased bicycling over the past nine years, and ten years of historic data that show vehicle volumes have remained reasonably constant.  Traffic modeling determined Alternative B may result in 3 to 46 seconds travel time increase for the average trip, 2 to 58 seconds increase for 95% of trips on the corridor, and 1 second to 2 minutes and 09 seconds increase for 5% or less of trips on the corridor. o Transportation research does not find vehicle lane repurposing results in increased emissions, instead it finds:  Traffic emissions reductions from congestion mitigation are not guaranteed and demand-based emissions reduction strategies can be more effective.2  Reduction in fine particulate emissions with multimodal improvements on a corridor.3 • The center turn lane provides dedicated space for day-to-day emergency response vehicles to travel unimpeded by roadway traffic. • Reconfiguring vehicle lanes provides space at intersections for more protected intersection elements which can reduce VZAP common crash types: right-turn crashes and pedestrians/bicyclists crossing the street. • Implementing traffic signal changes to separate turning vehicles from people walking and biking at major intersections to further reduce VZAP common crash types: left-turn crashes, right-turn crashes, and pedestrians/bicyclists crossing the street. 1 https://safety.fhwa.dot.gov/road_diets/guidance/info_guide/rdig.pdf 2 https://www.sciencedirect.com/science/article/abs/pii/S1361920912000727 3 https://www.sciencedirect.com/science/article/abs/pii/S1361920914001254 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 7 of 111 o Traffic signal changes for a two-way protected bike lane have less impact on vehicle travel time compared to one-way bike lanes because the two-way lane is only on one side of the street, while one-way lanes are on both sides. • The two-way protected bike facility on the north side of the street supports: o All ages and abilities by being wide enough to support side-by-side riding, such as parents with young children, and people biking or using scooters to pass one another. o Locating the protected bike lane on the north side of the street improves safety by significantly reducing the number of conflict points between people on bikes and other vehicles. o Disaster emergency response because it is wide enough to accommodate emergency vehicles during a disaster scenario. o Year-round maintenance because:  It is wide enough to accommodate more types of conventional maintenance vehicles for snow removal and sweeping.  Receives more sun exposure in the winter months, which encourages melting and evaporation to aid snow and ice response efforts.  Provides more space for snow storage in winter months. o Note: Alternative B will include design features such as protected intersection elements, raised crossings, two-way signs and markings, striping and signal changes that separate vehicle and bike movements at intersections, accounting for speed of vehicles and bicycles, to be detailed in the final design phase to reduce potential conflicts between bicyclists and drivers at side streets and driveways. • Implementing proven safety countermeasures within the existing roadway width, which costs less, takes less time to implement, and preserves the existing public street trees. • Concurrently implementing side street traffic calming and management in prioritized locations to address the biggest speeding problems on neighborhood streets. PUBLIC FEEDBACK The community engagement strategy for conceptual design of the Iris Avenue Transportation Improvements project consisted of three phases: 1. Summer—Winter 2023: Community Input on Travel and Lived Experience; 2. Winter—Spring 2024: Community Input on Conceptual Design Alternatives; and 3. Summer 2024: Community Input on CEAP and Recommended Alternative. Summer—Winter 2023: Community Input on Travel and Lived Experience From summer through winter 2023, staff began talking to the community and collecting data to understand their lived experience of what is working on Iris Avenue and what needs improvements. Twenty-seven engagement activities reached over 1,600 people and garnered more than 2,100 comments that provided feedback on existing conditions, challenges, and opportunities to inform development of improvements. 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 8 of 111 People participated in online questionnaires and in-person contacts at tabling, pop-up, and other community events. Guided walk and bike tours provided opportunities to get more detailed feedback from participants. This first round of project work culminated in an open house and three walks in the park in winter 2023. The project team shared learnings and provided additional opportunities for community members to offer feedback before city staff began identifying potential improvements. Themes heard from this engagement included: o East-west travel is important, and drivers appreciate Iris Avenue as a convenient and reliable route across the city o People walking, rolling, biking, and taking transit also want Iris Avenue to provide convenient and safe routes o Sidewalks could be improved to provide comfort, safety, and attractive walking conditions. Sidewalks are currently not wide enough, are winding, sloping, and bumpy, and are often blocked by overgrown vegetation o Crossing Iris Avenue safely and conveniently is a priority for people of all ages and abilities traveling to school, work, for errands, and for recreation – but today some see it as a barrier to getting where they want to go o Vehicles travel at high speeds, creating unsafe conditions and excessive street noise o Safer neighborhood and business access is essential o Drivers feel unsafe turning onto and off Iris Avenue and feel they’re more likely to crash with oncoming traffic when doing so o Delivery, transit, waste management and other vehicles stop in-lane, blocking the bike and right-side travel lanes o Residents are concerned any future changes will impact emergency evacuation and response o Neighbors want to maintain the character of their neighborhoods, which they see as providing safer, more comfortable alternatives for walking, rolling, and biking than arterial streets like Iris Avenue, and they are concerned that changes to Iris Avenue could create traffic diversion onto nearby streets o Community members want attractive facilities and opportunities for placemaking o Better wayfinding and help navigating to local and regional destinations are desired o Roadway pavement conditions could be improved o Transit service is infrequent, and many transit stops are not accessible and lack shelters, benches, and trash cans Winter—Spring 2024: Community Input on Conceptual Design Alternatives The design process took place from winter to spring 2024 and identified and screened potential solutions to issues highlighted by data and community input. These solutions were then compared and contrasted using 17 criteria and preliminary traffic modeling was undertaken to assess the feasibility of roadway reconfiguration with lane repurposing. Preliminary traffic analysis showed that vehicle lane changes at the Broadway and 28th Street intersections would significantly increase travel times by at least five minutes and cause vehicle queues exceeding 1,000 feet. To ensure reliable traffic flow and to respond to the community’s priority for vehicle travel time, repurposing vehicle lanes is not proposed at these critical 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 9 of 111 intersections. Instead, any lane configuration changes will be confined to the corridor section between 13th Street and Folsom/26th Street. The design process resulted in four conceptual alternatives being advanced for further evaluation between 13th Street and Folsom/26th Street: o Alternative A: One-Way Protected Bike Lanes and No Change to Roadway Width o Alternative B: Two-Way Protected Bike Lane and No Change to Roadway Width o Alternative C: One-Way Protected Bike Lanes and Widened Roadway o Alternative D: Two-Way Protected Bike Lane and Widened Roadway In spring 2024, staff hosted a second in-person and virtual open house, met people where they were at community pop-ups, and hosted an online questionnaire to understand the community’s priorities to advance the four conceptual alternative designs. Community input continued the themes heard in 2023. When asked for their priorities for designing Iris Avenue, questionnaire respondents’ answers grouped into three distinct tiers: greater than 100 selections, 20 to 100 selections, and less than 20 selections: o 100+ selections o Vehicle Travel Time Along the Corridor o Crash Reduction o Biking Comfort o Pedestrian Crossing Safety and Comfort o Bike Crossing Safety and Comfort o Vehicle Speed Moderation o Preserving Existing Trees o 20-100 selections o Disaster Emergency Response o Time and Cost to Design and Implement o Vehicle Turning Movements o Walking Comfort o Day-to-Day Emergency Response o Transit Accessibility o Opportunity for Protected Intersection Elements o Less than 20 selections o Stormwater Drainage o Right-of-Way Acquisition o Utility Relocation Summer 2024: Community Input on CEAP and Recommended Alternative In spring and summer 2024, staff completed the CEAP using the established CEAP goals assessment, checklist and checklist questions, project-specific evaluation criteria and community input to identify the recommended alternative. 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 10 of 111 Staff shared the CEAP evaluation and recommended alternative with the community for feedback in July and August 2024 at an in-person open house with 163 attendees and a virtual open house questionnaire which received 217 responses. The questionnaire focused on the alternatives evaluation process and the recommended alternative design elements the community is excited for and concerned about. The most mentioned concerns about the project for staff to consider in future design phases were: • Traffic congestion and vehicle travel time • Project process • Complexity of a center turn lane and two-way protected bike lane design • Neighborhood side street vehicle speeds and traffic diversion • Bookend intersection safety • Emergency evacuation When asked what design elements respondents and in-person open house participants are most excited about as the project moves forward, the most selected responses were: • Safer crossings • Preservation of Tree Canopy • End-to-end two-way protected bike lane • Protected intersections Themes from the most recent phase of community engagement reiterated previously heard concerns and desires and did not reveal new or diverging themes. These continued themes influenced the finalization of the content of the CEAP and public facing materials. Community feedback also provides the priorities on which to focus such as the south side sidewalks and access to the bike facility on the north side, the emphasis on high quality and aesthetically- pleasing design, innovative designs which preserve as much tree canopy as possible, and other designs and signal practices to best balance the trade-offs in safety, comfort, and connectivity for people walking, biking, riding transit and driving. Project information, including the online open house materials, can be found at the Iris Avenue Transportation Improvement Project website. BOARD ACTION REQUESTED Staff is seeking a recommendation to the City Council regarding the Iris Avenue Transportation Improvements Project CEAP. Findings will be presented to City Council for acceptance at their September 19, 2024 meeting. 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 11 of 111 ATTACHMENTS Attachment A – Iris Avenue Transportation Improvements Project Community and Environmental Assessment Process (CEAP) 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 12 of 111 Document Title Here Community and Environmental Assessment Process Iris Avenue Transportation Improvements Project September 2024 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 1 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 13 of 111 Table of Contents EXECUTIVE SUMMARY ........................................................................................................................................... 3 PROJECT DESCRIPTION ........................................................................................................................................... 4 BACKGROUND PURPOSE & NEED ........................................................................................................................... 5 Community Input on Travel and Lived Experience - 2023 .......................................................... 7 Existing Conditions Data ............................................................................................................. 9 CEAP EVALUATION............................................................................................................................................... 13 CEAP Process ............................................................................................................................. 13 Conceptual Alternatives ........................................................................................................ 13 Community Input on Conceptual Design Alternatives – Spring 2024 ...................................... 30 Goals Assessment ..................................................................................................................... 34 CEAP Checklist ........................................................................................................................... 38 Checklist Criteria Summary ................................................................................................... 38 Project Specific Evaluation Criteria ....................................................................................... 41 Community Input on CEAP and Recommended Alternative – Summer 2024.......................... 58 RECOMMENDED ALTERNATIVE ............................................................................................................................ 64 STAFF PROJECT MANAGER AND RELEVANT CONTACTS ........................................................................................ 67 ATTACHMENTS .................................................................................................................................................... 68 Attachment A: Conceptual Alternatives with Considerations Applied .................................... 69 Attachment B: CEAP Checklist Evaluation for the Four Conceptual Design Alternatives ........ 73 Attachment C: CEAP Checklist Questions ................................................................................. 75 Attachment D: Table of Mature Trees ...................................................................................... 91 Attachment E: Floodplain Memo .............................................................................................. 96 Attachment F: Conceptual Alternatives with Project-Specific Evaluation Criteria Applied ..... 99 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 2 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 14 of 111 Executive Summary The Iris Avenue Transportation Improvements Project Community and Environmental Assessment Process (CEAP) completed a full project evaluation of four conceptual design alternatives. The CEAP used the established CEAP goals assessment, checklist and checklist questions, project-specific evaluation criteria, and community input to identify the recommended alternative. The recommend alternative is Alternative B. The project will advance the actions of the Vision Zero Action Plan by implementing proven safety countermeasures on this priority Core Arterial Network (CAN) corridor that is also on the High Risk Network (HRN). The HRN is a small percentage (7%) of city streets that have nearly half of all fatal and serious injury crashes in the city. The CAN is a connected system of protected bicycle lanes, intersection enhancements, pedestrian facilities, and transit facility upgrades to create safe, comfortable connections along Boulder’s main corridors. The CEAP for the Iris Avenue Transportation Improvements project included robust community and stakeholder engagement, analysis of existing conditions data, consideration of policy and plan guidance, and evaluation of conceptual alternatives using a CEAP checklist and project specific evaluation criteria. The CEAP identified Alternative B as the recommended alternative because it best balances community priorities, plan and policy guidance, and issues identified by the existing conditions data which demonstrate the need for crash reduction, moderating vehicle speeds, maintaining travel time reliability, providing bike and pedestrian safety and comfort, and preserving existing public street trees. Alternative B can achieve these safety benefits with minimal added travel time and lower costs and time to implement than other conceptual design alternatives. Alternative B reconfigures vehicle lanes between 13th Street and Folsom/26th Street from four to three, including a center turn lane, incorporates protected intersection elements, implements traffic signal changes to separate turning vehicles from people walking and biking at major intersections, makes spot improvements to existing sidewalks, and provides a two-way protected bike lane on the north side of the street. The recommended alternative does not change the vehicle lane configuration at “the bookends” from 13th Street to Broadway and Folsom/26th Street to 28th Street to maintain travel time reliability for all roadway users. The center turn lane and two-way protected bike lane each provide dedicated space for emergency response during day-to-day and disaster scenarios respectively. The project team will continue to coordinate closely with the city’s Boulder-Fire Rescue and Police departments, and the Office of Disaster Management (ODM) for the City of Boulder and Boulder County, on roadway design features for emergency operations during the final, or detailed, design phase. Adjacent communities expressed concerns around traffic diversion on side streets. This project will include a concurrent neighborhood traffic calming effort on select streets in the secondary study area to address speed mitigation and traffic management. Access control is another tool in the design toolbox that can limit traffic diversion. Existing conditions volume and speed data was collected in the secondary study area to inform the traffic calming approach and locations. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 3 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 15 of 111 Alternative B can be implemented within the existing curb-to-curb width and so preserves existing public street trees. It is estimated, based on recently completed similar projects, to cost about $5 million in today’s dollars to implement and take three to four times less time to implement than alternatives that maintain the existing number of vehicle lanes. Traffic modeling completed for the project found these benefits can be achieved with a potential travel time increase ranging from 2 to 58 seconds for 95% of trips on the corridor, and the slowest trips (5% of trips) with a maximum of 2 minutes and 9 seconds. Project Description Iris Avenue, from 28th Street to Broadway, is an important east-west corridor in north Boulder that provides direct, convenient connections to everyday neighborhood destinations and supports travel within Boulder and between Boulder and communities along the Diagonal Highway (Figure 1). Figure 1: Iris Avenue Priority Corridor project limits Locally, Iris Avenue is recognized by the Denver Regional Council of Governments (DRCOG) as a short trip opportunity zone: an area where a high concentration of short trips of two miles or less begin or end. Short trips are much more likely than longer trips to be converted from vehicle trips to walking or bicycling. The CO 119 Safety, Mobility and Bikeway Project will bring regional multimodal transportation improvements, including bus rapid transit and off-street multi-use path connections to the eastern edge of the project corridor (Figure 2). Construction begins this year and is anticipated to be completed in 2026/2027. The bus rapid transit service will have stops on 28th Street just south of Iris Avenue and the bikeway will connect to the city’s existing bike network west of 47th Street and along Foothills Parkway. Regional bus rapid transit and e-bike supportive multi- use paths to the eastern edge of Iris Avenue make it a key multimodal corridor. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 4 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 16 of 111 Figure 2: CO 119 Safety, Mobility and Bikeway project overview map Despite the role that Iris Avenue plays within the overall multimodal transportation network, it does not provide the safest, most comfortable connections regardless of how you travel. The Iris Avenue Transportation Improvements Project identified ways to make Iris Avenue, between Broadway and 28th Street safer, more comfortable, and better connected. The project improvements focus on increasing mobility choices, improving safety for everyone, making walking, bicycling and taking transit more attractive and convenient, and improving connections to local and citywide destinations. Background Purpose & Need In 2019, the Transportation Master Plan and the Low Stress Walk and Bike Network Plan recommended greater separation and protection between vehicle and bicycle lanes on Iris Avenue and a need for pedestrian improvements in key areas due to the road having more than Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 5 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 17 of 111 three vehicle lanes, the posted speed limit set at 35 miles per hour, and average daily traffic being greater than 6,000 vehicles.1 In 2022 the Safe Streets Report (SSR) 2 found between 2018 and 2020, 14,500 people were involved in a crash in Boulder, resulting in 150 serious injuries. Sixty-seven percent of severe traffic crashes, those that result in serious injury or fatality, occur on arterial streets. The report found these severe injury crashes occurred at several intersections on Iris Avenue: 28th Street, Folsom/26th Street, and Broadway. The SSR also identified Areas of Concern: crash types that disproportionately affect certain groups, like young people and seniors. Data from the Iris Avenue project revealed that one in ten pedestrians or cyclists traveling on or across Iris Avenue on an average day are young, elderly, or disabled. Community input shared a common sentiment: people feel unsafe walking or biking along and across Iris, yet hundreds do so every day. In response to the findings of the SSR, City Council, in partnership with the Transportation Advisory Board (TAB), elevated work on the Core Arterial Network (CAN) as one of its 10 priorities for city department efforts. Council reaffirmed CAN as a priority in April 2024. The CAN is the connected system of protected bicycle lanes, intersection enhancements, pedestrian facilities, and transit facility upgrades that will help reduce the potential for severe crashes and make it more comfortable and convenient for people to get where they need to go along Boulder’s main corridors, including Iris Avenue. In 2023, the 2023-2027 Vision Zero Action Plan (VZAP) identified specific actions and strategies to address the findings of the SSR. The High Risk Network (HRN) was developed as part of the plan as a way to focus actions on places where severe crashes occur or are more likely to occur in the future. The HRN has an outsized proportion of previous severe crash incidence: the HRN represents only 7% of the city’s street network but nearly half of all severe crashes occur on these streets. The HRN also identifies locations where five or more of the six most common risk factors for future crashes are present.3 Proactively managing risk and mitigating crashes on this small percentage of streets can have an outsized impact on reducing fatal and serious injury crashes citywide and achieve the greatest impact in the shortest amount of time. Iris Avenue, from 19th to 28th streets, is on the HRN. Two core strategies of the VZAP are to work on the CAN and the HRN. Action 3 of the plan commits the city to implement capital projects by 2027 to improve safety and comfort on priority CAN corridors that are also on the HRN, including Iris Avenue. The Iris Avenue Transportation Improvements Project recommended alternative includes proven safety countermeasures, such as protected bike lanes, protected intersections, and roadway reconfiguration. Proven Safety Countermeasures are transportation designs and strategies that 1 https://bouldercolorado.gov/media/4530/download?inline= 2 https://bouldercolorado.gov/media/7841/download?inline= 3 Daily vehicle traffic between 5,000 and 10,000 per travel lane, Signalized intersections, Major unsignalized intersection, Businesses and a mix of land uses present, and 85% of vehicle speeds at or above 30 mph Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 6 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 18 of 111 the Federal Highway Administration (FHWA) recognizes as effective at reducing severe crashes.4 Community Input on Travel and Lived Experience - 2023 From summer through winter 2023, staff began talking to the community and collecting data to understand their lived experience of what is working on Iris Avenue and what needs improvements. Twenty-seven engagement activities reached over 1,600 people and garnered more than 2,100 comments that provided feedback on existing conditions, challenges, and opportunities to inform development of improvements (Table 1). People participated in online questionnaires and in-person contacts at tabling, pop-up, and other community events. Guided walk and bike tours provided opportunities to get more detailed feedback from participants. This first round of engagement culminated in an open house and three walks in the park where the project team shared learnings and provided additional opportunities for community members to offer feedback before city staff began identifying potential improvements. Table 1: Summary of 2023 community engagement activities 2023   Engagement Event Date Participants Summer Webpage and Press release 7/28/2023   Virtual Questionnaire 1 7/28/2023 772 National Night Out 8/1/2023 10 Inside Boulder News Segment 8/7/2023   Red Oak Park Bike Giveaway 8/9/2023 50 What's Up Boulder 8/10/2023 50 Columbine Back to School Day 8/15/2023 50 RTD Stop Pop Up 8/17/2023 40 Safeway Pop Up 8/18/2023 25 Business Outreach Door- knocking 8/18/2024 30 Listening Sessions 8/18/2024 8 Foothill Back to School Night 8/30/2023 30 CU Bike fest 8/31/2023 20 Elmer's Twomile Pop Up 9/6/2023 50 Growing Gardens Pop Up 9/13/2023 40 FUNKtion at Boulder Junction 9/14/2023 5 Fall/Winter Fall Transportation Safety Fair 9/16/2023 25 Guided Walking Tour 9/19/2023 24 Guided Biking Tour 9/19/2023 32 BHP Iris/Hawthorn Block Party 9/21/2023 45 4 https://highways.dot.gov/safety/proven-safety-countermeasures Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 7 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 19 of 111 2023   Engagement Event Date Participants CPWD Accessible Roll and Stroll 9/28/2023 2 Growing Up Boulder Walk 9/28/2023 26 Smarthome-Imagine! 9/29/2023 1 Press Release 10/11/2023 Open House 10/24/2023 103 Virtual Open House Questionnaire 10/24/2023 162 Walk in the Park Parkside Park 12/2/2023 28 Walk in the Park Columbine Park 12/9/2023 31 Walk in the Park Melody Park 12/16/2023 32 Total 1,691 Themes heard from this engagement included: • East-west travel is important, and drivers appreciate Iris Avenue as a convenient and reliable route across the city • People walking, rolling, biking, and taking transit also want Iris Avenue to provide convenient and safe routes • Sidewalks could be improved to provide comfort, safety, and attractive walking conditions. Sidewalks are currently not wide enough, are winding, sloping, and bumpy, and are often blocked by overgrown vegetation • Crossing Iris Avenue safely and conveniently is a priority for people of all ages and abilities traveling to school, work, for errands, and for recreation – but today some see it as a barrier to getting where they want to go • Vehicles travel at high speeds, creating unsafe conditions and excessive street noise • Safer neighborhood and business access is essential • Drivers feel unsafe turning onto and off Iris Avenue and feel they’re more likely to crash with oncoming traffic when doing so • Delivery, transit, waste management and other vehicles stop in-lane, blocking the bike and right-side travel lanes • Residents are concerned any future changes will impact emergency evacuation and response • Neighbors want to maintain the character of their neighborhoods, which they see as providing safer, more comfortable alternatives for walking, rolling, and biking than arterial streets like Iris Avenue, and they are concerned that changes to Iris Avenue could create traffic diversion onto nearby streets • Community members want attractive facilities and opportunities for placemaking • Better wayfinding and help navigating to local and regional destinations are desired • Roadway pavement conditions could be improved Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 8 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 20 of 111 •Transit service is infrequent, and many transit stops are not accessible and lack shelters, benches, and trash cans Public input from 2024 community engagement activities is summarized in the sections of this memorandum corresponding to the associated component of the conceptual design process. Existing Conditions Data Data collection and analysis conducted concurrently with engagement supports the findings from the city’s plans and feedback from the community. Existing conditions data collected between September and October 2023 found the following: •Speeds (Figure 3): o Prevailing speeds are 5 or more miles per hour over the speed limit from Broadway to Folsom/26th Street o Between 19th Street and Folsom/26th Street, 5.7% of eastbound drivers are speeding 10 miles per hour or more over the posted speed limit; this equates to every 17th vehicle excessively speeding Figure 3: Median, Prevailing and Top-End speeders on Iris Avenue from Broadway to East of Folsom/26th Street •Number of vehicles (Figure 4): o Average daily vehicle volumes vary along the corridor but are evenly split by direction: East of 16th Street: 15,930 vehicles per day East of 19th Street: 20,040 vehicles per day East of 26th Street: 21,350 vehicles per day Vehicle volumes are higher in the westbound direction in the morning hours and higher in the eastbound direction in the evening hours Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 9 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 21 of 111 Figure 4: Iris Avenue corridor daily traffic volume and direction data o Existing Travel Time (Figure 5): Time to travel by vehicle from one end to the other on Iris Avenue varies by direction, time of day and seasonal variability, such as school being in session. •Average vehicle is about 3 – 4 minutes •Most vehicle trips range from 4 – 5 minutes Figure 5: Existing travel times for Iris Avenue in the morning, mid-day and evening •Multimodal Travel: o An average of 100 people walk, 130 people bike and 100 people ride transit along Iris Avenue on an average day. •Crossing Iris Avenue (Figure 6): o Over 1,000 people walk, bike, or roll across Iris Avenue on an average day 409 walk and 406 bike through the Elmer’s Twomile underpass Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 10 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 22 of 111 Figure 6: Pedestrian and bicycle crossing data for Iris Avenue • Transit (Figure 7) o Though transit is relatively infrequent on Iris Avenue (60-minute headways), transit on either end (Broadway and 28th Street) is frequent and has high ridership.  About 100 people a day take Route 208, which runs along Iris Avenue and provides critical east-west connections  Routes 204, 205, SKIP, BOLT, and Bound cross Iris Avenue and provide greater transit frequency at up to 10-minute headways during peak travel times • The SKIP, BOLT, and BOUND see some of the highest area ridership Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 11 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 23 of 111 Figure 7: Transit service on and connecting to Iris Avenue • Trees o There are 150 public street trees along Iris Avenue o These trees provide the Iris Avenue project area with 25% canopy cover5 o Citywide overall canopy cover is 16% Crash Data Crash data from 2016 through 2023 found the following: o 345 vehicle crashes, or roughly 43 per year, happened on Iris Avenue, six of those were severe crashes (Figure 8)  143 crashes were rear ends  58 crashes were approach turn crashes, involving cars turning across oncoming traffic Figure 8: Crash density of all crashes on Iris Avenue (2016-2023)  22 crashes involved people walking (4) and biking (18) (Figure 9) 5 https://bouldercolorado.gov/sites/default/files/2021-05/boulderufspv2018.pdf Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 12 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 24 of 111 o 45% of these crashes were at the Folsom/26th Street intersection o All crashes involved a driver striking the person walking or biking o 19 of the 22 crashes occurred because the driver did not yield to the person walking or biking at an intersection or driveway o More crashes with people walking or biking occurred at the Folsom/26th Street intersection (10) than at either of the busiest intersections on the corridor: 28th Street (8) and Broadway (2) Figure 9: Pedestrian and bicycle crash data on Iris Avenue (2016-2023) CEAP Evaluation The Community and Environmental Assessment Process (CEAP) provides formal evaluation of potential improvements and conceptual design alternatives. CEAP Process The CEAP helps identify a recommended alternative through five steps: 1) Screen potential improvements to identify conceptual alternatives, 2) Compare and contrast conceptual design alternatives and share the results with the community to receive input on their priorities, 3) Draft the CEAP evaluation, using the CEAP checklist and defined project specific evaluation criteria, and identify the recommended alternative 4) Present the CEAP evaluation and recommended alternative to the community for feedback 5) Finalize the CEAP evaluation and recommended alternative, considering public input, to present to Transportation Advisory Board and City Council for their recommendation and action. Conceptual Alternatives Staff consulted best practices, design standards, and guidelines to identify all potential solutions to the issues identified by the data and community engagement. 1. Screening This list of improvements was then screened using eight screening criteria: traffic safety, transportation operations, sustaining the tree canopy, implementation feasibility, and safe and Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 13 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 25 of 111 comfortable connections. The criteria were applied corridor wide, from Broadway to 28th Street, and to four distinct segments: 1. Broadway to 16th St 2. 16th St to 19th St 3. 19th St to 26th St 4. 26th St to 28th St The eight screening criteria were applied using available data or professional judgment when data was not available. No criteria were weighted. Criteria marked with an asterisk (*) were identified by the community during engagement in 2023. Potential to Reduce Speeds* Purpose: Almost one in five (19%) severe crashes involve speeding vehicles 6 and people report speeding is a top four traffic safety concern in the City of Boulder7. The Transportation Master Plan recommends implementing specific safety countermeasures and employing proven effective safe and innovative intersection and corridor treatments to improve transportation safety for all people of all ages using any mode within the transportation system. Definition: Fewer lanes or a visually narrowed roadway reduce speeds. Source: Federal Highway Administration Road Diet Information Guide Comparison: To existing conditions Provides Space for All Modes* Purpose: The Transportation Master Plan prioritizes safe and complete streets to provide a comfortable transportation network for people of all ages and abilities through key actions including designing for separation between vehicles, cyclists and pedestrians8. Definition: Every mode (vehicle, bicycle, pedestrian, transit) is provided minimum width facilities Source: City of Boulder Design and Construction Standards Comparison: To existing conditions Advances Adopted Plans Purpose: The Transportation Master Plan is the guiding policy document for the City of Boulder’s transportation system. The Low-Stress Walk and Bike Network Plan is part of the Transportation Master Plan. The goal of the Low-Stress Walk and Bike Network Plan is to attract a broader population of people (ages 8 to 80) as confident and comfortable pedestrians and cyclists. The Vision Zero Action Plan identifies specific actions and strategies to address different traffic concerns and create safer streets. Definition: Meets recommendations of adopted city transportation plans Source: Transportation Master Plan (2019), Low Stress Walk and Bike Network Plan (2019), and Vision Zero Action Plan (2023-2027) 6 City of Boulder, Vision Zero Boulder Safe Streets Report (Transportation & Mobility, 2019) 7 City of Boulder, Boulder Vision Zero Action Plan (Transportation & Mobility, 2023) 8 City of Boulder, Boulder Transportation Master Plan (Initiative, Transportation & Mobility, 2019) Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 14 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 26 of 111 Comparison: To existing conditions Impact to Traffic Operations* Purpose: The Transportation Master Plan objective seven seeks to maintain 1994 levels of travel time on Boulder arterial streets and improve travel time reliability and predictability as measured by person travel time and throughput on arterials (autos and transit) and intersection Level of Service (LOS) and delay. Community engagement identified vehicle travel time as important for Iris Avenue. Definition: Potential to increase vehicle delay and queue lengths at intersections Source: Professional judgment based on traffic analysis of existing and proposed conditions within the Existing Conditions Report and Traffic Analysis. Comparison: To existing conditions Impact to Right-Of-Way Purpose: The Transportation Master Plan Advanced Mobility Policies calls to reallocate the right-of-way as appropriate to prioritize movement of people through transit, bicycle, pedestrian improvements, and public placemaking. Definition: Requires Right-of-Way to implement Source: City of Boulder Parcels data Comparison: None; options are scored based on the number of easements required Impact to Floodplain Purpose: The City of Boulder's floodplain regulations are designed to reduce risk to life and property in areas along the 16 major drainageways within the city limits. Definition: Narrowing the existing curb-to-curb width has potential to cause a rise in the floodplain Source: Professional judgment, staff and floodplain consultant Comparison: None; options are scored based on the anticipated level of impact to the floodplain. If professional judgment determines an option’s impact to floodplain could not be mitigated, the option will not be advanced. Impact to Existing Trees* Reasoning: The City of Boulder Forestry is committed to maintaining a healthy and safe urban forest as well as preserving an extensive and diverse tree cover for future generations. Community engagement identified existing trees as important for Iris Avenue. Definition: Amount of tree removals required Source: City of Boulder Forestry tree inventory for the project area Comparison: None; options are scored based on the number of trees removed Cost to Implement* Reasoning: Transportation funding is limited and highly dependent on sales tax -- and transportation dedicated sales tax revenue is not keeping up with inflation resulting in declining purchasing power. Further, the city is facing increased competition for regional, state and federal funding. Definition: Estimated cost to implement Source: Professional judgment Comparison: To each other Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 15 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 27 of 111 Screening Summary The results of the screening are summarized in (Figure 10). Figure 10: Potential improvements screening results Traffic Operations Travel forecasts from the Denver Regional Council of Governments (DRCOG) for 2040 are one of many key inputs in vehicle operations analyses conducted in the region. For example, the current CO 119 Safety, Mobility and Bikeway Project led by the Colorado Department of Transportation (CDOT) conducted such travel forecasts which project a 25% increase 9 in vehicle traffic along the Diagonal Highway between Boulder and Longmont by 2040. The Boulder Valley Comprehensive Plan transit and land use policy assumptions reduce the DRCOG projected increase in vehicle trips. These assumptions are supported by historic traffic volumes on Iris Avenue where 10 years of data show the number of vehicles driving the corridor have remained reasonably constant: between 21,200 and 23,900 vehicles per day east of 19th Street. The City of Boulder Modal Shift in the Boulder Valley 2023 Travel Diary Study validates these data and assumptions when it found decreases in single occupancy vehicle 9 https://www.codot.gov/projects/co119-mobility/design Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 16 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 28 of 111 (SOV) (by 9.1 percent) and increased trips made by bicycle (by 8.4 percent) between 1990 and 2023. Therefore, traffic operations modeling for the project used existing vehicle, bicycle, and pedestrian volumes. The analysis found traffic volumes on CO 119 and Iris Avenue decrease as you move from east to west along the corridor. The County data indicates daily volumes are over 40,000 vehicles per day (vpd) east of Foothills Parkway, dropping to around 30,000 vpd west of Foothills Parkway and again to around 26,000 vpd east of 28th Street. The field data collected suggests this volume drops further on Iris Avenue, to around 21,000 vpd west of 28th Street, 20,000 vpd west of 26th Street, and 16,000 vpd west of 19th Street. Federal Highway Administration (FHWA) guidance states that lane repurposing is typically implemented on roadways with an average daily traffic of 25,000 vehicles or fewer. According to this guidance, a 25% growth in current vehicle volumes on Iris Avenue would still be within range of the FHWA guidance for lane repurposing. Iris Avenue lane repurposing impacts to traffic operations were evaluated using Synchro v11 traffic capacity analysis software. Vehicle travel lanes were modeled eastbound and westbound at the intersections of 19th Street and Folsom/26th Street and at the “bookends” of the corridor, Broadway and 28th Street. The bookends analysis at the Broadway intersection included reducing to a single westbound left turn lane was evaluated. At 28th Street, reducing to a single eastbound and westbound through lane was evaluated, with reduction to a single northbound left turn lane also required. Preliminary traffic analysis of these changes at the bookends found a significant increase in travel time, by five minutes or more, and vehicle queuing exceeding 1,000 feet at some intersections. Ultimately, the project team decided not to advance proposals for any changes to the vehicle lanes at these critical intersections to maintain reliable traffic movement into and out of the corridor. The final determination was that any potential changes to the vehicle lane configuration would be limited to the segment of the corridor that is located between 13th Street and Folsom/26th Street. Preliminary traffic analysis of these changes to the 19th Street and Folsom/26th Street intersections considered impacts to travel time, vehicle level of service (LOS), the volume of vehicles to roadway capacity ratio, and vehicle queue lengths. This analysis used current vehicle signal phasing at these two intersections. The analysis found travel time and vehicle queue lengths increased within an acceptable level at these intersections, the LOS remained at current levels, and vehicle volume to roadway capacity ratios are at or less than 0.8, which indicates three vehicle lanes provides sufficient capacity for the number of vehicles that use Iris Avenue. All advanced conceptual alternatives include end-to-end bike and pedestrian improvements for people that walk and bike to shops and businesses and access local and regional transit service. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 17 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 29 of 111 At the Broadway bookend, people walking, biking, and taking the bus will have improved connections and design features, such as shared bus stops, to better organize space along and across the street for safer travel. At the 28th Street bookend, people walking, biking, and rolling will have separate spaces and improved connections to Elmer’s Twomile multi-use path, 28th Street, and local and regional multi-use paths and transit service. The 28th Street bookend receives high activity as people access commercial centers and enter and exit the corridor. Conflicts arise when all this activity crosses one another. When crash data demonstrate these crossings are unsafe, limiting those conflicts is needed. Access management, where turns are restricted, can reduce the potential for crashes. Access Management The project will provide access management, including prohibition of westbound left turns, at the western-most driveway to the Safeway shopping complex due to a crash history of westbound vehicles traveling along Iris Avenue turning left into the driveway (2016 to 2023): 12 crashes with three involving people biking (Figure 11). Figure 11: Safeway Driveway Crash History Neighborhood Streets In addition to speeding on Iris Avenue, speeding on parallel side streets is a community concern that affects the safety and quality of life of residents and users of those streets. Some cut- through traffic diversion on these side streets may occur today and neighbors have identified Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 18 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 30 of 111 streets where they experience high vehicle speeds. Staff added to this list to make it inclusive of all potential parallel vehicle routes. The list of street segments, with the number and prevailing vehicle speeds, are shown in Figure 12. In response to community feedback about side street vehicle speeding and concerns about increased traffic diversion, staff added a secondary study area to examine the potential for neighborhood traffic calming to the Iris Avenue project scope. As the Iris Avenue design progresses, staff will identify the specific locations along these street segments in the secondary study area to receive speed mitigation and traffic management as a concurrent project. Street segments with the greatest speeding issue will be prioritized first. These prioritized segments will receive speed mitigation and traffic management when the Iris Avenue project is implemented, following final design and allocation of funding. This may include treatments such as speed humps, speed tables, and vehicle turn restrictions. Figure 12: Secondary study area with parallel street 2. Conceptual Design Alternatives The screening resulted in four conceptual alternatives being advanced for further evaluation: • Alternative A: One-Way Protected Bike Lanes and No Change to Roadway Width Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 19 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 31 of 111 • Alternative B: Two-Way Protected Bike Lane and No Change to Roadway Width • Alternative C: One-Way Protected Bike Lanes and Widened Roadway • Alternative D: Two-Way Protected Bike Lane and Widened Roadway Alternative A One-Way Protected Bike Lanes and No Change to Roadway Width (Figure 13) • Three vehicle lanes and on-street protected bike lanes meeting minimum design widths with spot improvements to sidewalks behind the curb  A typical roadway cross section includes: • Two 10.5-foot travel lanes (one eastbound, one westbound) • One 10-foot center turn lane • Two five-foot bicycle lanes (one eastbound, one westbound) meeting minimum design widths separated from the travel lane by three-foot protected buffers • Two 1.5-foot gutters (one on north side and one on south side of the street)  Roadway Impact: Minimal to no change to existing curb to curb width  Behind the curb: • Spot improvements to 5-foot typical existing sidewalks • 0 – 8-foot typical existing planting area Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 20 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 32 of 111 Figure 13: Alternative A: One-Way Protected Bike Lanes and No Change to Roadway Width Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 21 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 33 of 111 Alternative B Two-Way Protected Bike Lane and No Change to Roadway Width (Figure 14) • Three vehicle lanes with north side on-street two-way protected bicycle lane with spot improvements to sidewalks behind the curb • A typical roadway cross section includes: • Two 11-foot travel lanes (one eastbound, one westbound) • One 10-foot center turn lane • One 10-foot two-way protected bike lane (meeting minimum design widths with five-foot travel lane in each direction) with one five-foot protected buffer between the westbound travel lane and the protected bike lane on the north side of the street • Roadway Impact: Minimal to no change to existing curb to curb width • Behind the curb: • Spot improvements to 5-foot typical existing sidewalks • 0 – 8-foot typical existing planting area Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 22 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 34 of 111 Figure 14: Alternative B: Two-Way Protected Bike Lane and No Change to Roadway Width Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 23 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 35 of 111 Alternative C One-Way Protected Bike Lanes and Widened Roadway by approximately 11-feet (Figure 15) • Four vehicle lanes with on-street protected bike lane meeting minimum widths and with sidewalk widening behind the curb • A typical roadway cross section includes: o Four travel lanes (eastbound: one 10-foot and one 11-foot travel lane; westbound: one 10-foot and one 11-foot travel lane) o Two five-foot one-way bicycle lanes (one eastbound, one westbound) meeting minimum design widths separated from the travel lane by three-foot protected buffers • Roadway Impact: Widened curb to curb width by approximately 11-feet • Behind the curb: o South side variable width (0 – 8-foot) buffer/planting area where feasible o Six-foot wide sidewalk on north and south sides o 0 – 8-foot typical existing planting area on the north and south sides Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 24 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 36 of 111 Figure 15 Alternative C: One-Way Protected Bike Lanes and Widened Roadway Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 25 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 37 of 111 Alternative D Two-Way Protected Bike Lane and Widened Roadway by approximately eight feet (Figure 16) • Four vehicle lanes with north side on-street protected two-way bike lane with sidewalk widening behind the curb on the north side and spot improvements behind to sidewalk the curb on the south side • A typical roadway cross section includes: o Four travel lanes (eastbound: one 10-foot and one 11-foot travel lane; westbound: one 10-foot and one 11-foot travel lane) o One 10-foot two-way protected bike lane (meeting minimum design widths with 5-foot travel lane in each direction) with 3-foot protected buffer between the westbound travel lane and the protected bike lane • Roadway Impact: Widened to the north by approximately eight feet with the existing south side curb remaining in place • Behind the curb: o Six-foot sidewalk on the north side of the road o Spot improvements to 5-foot typical existing south side sidewalk o 0 – 8-foot typical existing planting area on the north and south sides Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 26 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 38 of 111 Figure 16: Alternative D: Two-Way Protected Bike Lane and Widened Roadway Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 27 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 39 of 111 Considerations The four conceptual alternatives were compared and contrasted by applying 17 considerations to each alternative between 13th Street and Folsom/26th Street. The 17 considerations were organized into five categories: 1. Traffic Safety a. Vehicle speed moderation b. Crash reduction 2. Safe and Comfortable Connections a. Biking comfort b. Walking comfort c. Opportunity for protected intersection elements d. Transit accessibility and reduction of bike/bus conflict e. Crossing safety & comfort 3. Transportation Operations a. Vehicle travel time along the corridor b. Vehicle turning movements c. Day-to-day emergency response use d. Disaster emergency response 4. Implementation Feasibility a. Time to design and implement b. Cost to implement c. Right-of-Way and property acquisition d. Utility relocation (under and above ground) e. Stormwater drainage 5. Sustaining the Tree Canopy a. Preserves existing trees Consideration Definitions Traffic Safety Potential to reduce speeds and severe crashes on the corridor. Vehicle speed moderation Assessed whether the alternative can reduce lane widths, the number of vehicle lanes or provide visual narrowing through bike separation or trees. Crash reduction Assessed for whether the alternative can reduce the number or severity of crashes by introducing turn lanes, reducing conflict points, separating vulnerable road users or reducing speeds. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 28 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 40 of 111 Safe and Comfortable Connections Potential to enhance residential, neighborhood, and business access, low stress walk and bike connections, and transit experience. Biking comfort Assessed for whether the alternative can implement the City of Boulder Low Stress Walk and Bike Network Plan recommendation. Walking comfort Assessed for whether the alternative can reduce the City of Boulder Low Stress Walk and Bike Network Plan pedestrian stress factors. Opportunity for protected intersection elements Assessed for whether the alternative can provide space for protected intersection elements. Transit accessibility and reduction of bike/bus conflict Assessed for whether the alternative provides safe transit vehicle and transit user interaction with travel lanes, bike lanes, and sidewalk. Crossing safety & comfort Assessed for whether the alternative can provide space for safer roadway crossings, like pedestrian refuge islands. Transportation Operations Analysis of the potential impact on vehicle travel time, vehicle turning movements, and emergency response. Vehicle travel time along the corridor Assessed for whether the alternative could change existing travel time with providing vehicle travel or turn lanes. Vehicle turning movements Assessed for whether the alternative could provide safer turning movements by including turn lanes and center turn lanes. Day-to-day emergency response use Assessed by Boulder County Office of Disaster Management and City of Boulder Fire and Police departments for whether the alternative changes current day-to-day emergency response. Disaster emergency response Assessed by Boulder County Office of Disaster Management and City of Boulder Fire and Police departments for whether the alternative changes disaster emergency response. Implementation Feasibility The amount of time and cost needed to design and implement the project. Time to design and implement Assessed for how the alternative compares to other alternatives in design and implementation needs. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 29 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 41 of 111 Cost to implement Assessed how the alternative compares to other alternatives in time and effort to design and implement. Right-of-Way and property acquisition Assessed how the alternative compares to other alternatives in the number of easements that would be required to implement. Utility relocation (under and above ground) Assessed for how the alternative compares to other alternatives in the number of utilities, above and below ground, that would need to be relocated to implement. Stormwater drainage Assessed for how the alternative compares to other alternatives in the amount of existing storm drainage, storm water and sanitary sewer infrastructure that would be impacted or new infrastructure built. Sustaining the Tree Canopy Potential to preserve existing street trees and maintain the current tree canopy. Preserves existing trees Assessed for whether the alternative keeps or removes existing street trees. Design Alternatives Assessment To assist the community, board members, and elected officials in understanding the differences between the four conceptual design alternatives, the considerations were assessed using existing conditions data, field reviews, preliminary transportation analysis, and professional judgment. Each consideration, excluding Implementation Feasibility, was assessed for how it would impact each alternative compared to today: (+) Improvement over today, (-) Worse than today, and (0) Same as today. Each alternative was assessed for the Implementation Feasibility considerations compared to each other for having: (↑) More impacts, (↓) Less impacts, or (/) No impact. The results of applying the considerations to each of the four alternatives can be found in Attachment A. Community Input on Conceptual Design Alternatives – Spring 2024 Throughout the spring of 2024, staff sought to understand the community’s priorities to advance the four conceptual alternative designs. Community feedback was solicited at an in- person open house on April 27 and an online open house in both English and Spanish hosted from April 27 through May 27. Staff also went into the community to meet with people where they were - at the North Boulder Recreation Center, in neighborhood parks, and at the Wednesday and Saturday farmers markets (Table 2). Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 30 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 42 of 111 Table 2: Summary of spring 2024 engagement events 2024   Engagement Event Date Participants Spring Press Release 4/9/2024   Open House 4/27/2024 203 Virtual Open House Questionnaire 4/27/2024 411 Continuing Conversation North Boulder Rec 4/30/2024 34 Emails to TAB and City Council 5/1/2024 53 Continuing Conversation Columbine 5/8/2024 22 Wednesday Farmers Market 5/15/2024 89 Continuing Conversation Parkside Park 5/16/2024 38 Saturday Farmers Market 5/18/2024 103 Columbine Elementary Bici Bus 5/22/2024 25 Total 942 With a total of 942 interactions, more than 500 people participated in face-to-face conversations with staff and with each other and 411 people completed the project questionnaire to share their priorities and feedback. Community input in 2024 continued the themes heard in 2023, though the levels of agreement among the community varied. These in-person and online conversations made clear that for every person who opposed any change on Iris Avenue there was someone else who supported changes to the street. As is often the case, most folks fell towards “the middle” than those who were strongly for or against the proposed changes. “I know Iris can still move cars while making the roadway much safer for everyone.” Boulder County resident who commutes on Iris Most everyone agrees that speeding on Iris Avenue needs to be addressed. There is also agreement that getting in and out of side streets and the shopping complexes near 28th Street feels unsafe. “Even though Iris Avenue serves as a major connection between Diagonal and Broadway, it should not be a speedway. I would like to see the speed limit kept low for the safety of all. Everything is easier and safer if people drive slowly.” Community member who lives along Iris Families, especially with young children, do not feel safe or comfortable walking, biking, or rolling along or across Iris Avenue – but do so to get to school or one of the several childcare centers nearby. “I walk my kids to daycare at 26th and Iris every day. That intersection is very dangerous.” Palo Park parent who travels across Iris daily Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 31 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 43 of 111 Nearby residents want Iris Avenue improved but are concerned changes would create cut- through traffic on their streets. “I do not want changes on Iris to cause traffic to divert to side streets, which some already does because people do not want to make the left turn onto Iris from Broadway. Living on Norwood, I see an increasing amount of commuter traffic, some of it related to Centennial Middle School, but some related to Iris. I myself divert onto Grape to avoid Iris between Folsom and 19th.” North Boulder resident who drives and bikes on and across Iris Avenue Some neighbors ask to have bike lanes removed from Iris Avenue and installed on parallel streets instead. “I use a bike, but I travel the neighborhoods to the south of Iris. Move the bikes to those less traveled streets where biking will be more enjoyable and safer. That is the better solution.” North Boulder resident who drives Iris Avenue but bikes on neighborhood streets Many people who bike want Iris Avenue to have protected bike lanes for the direct connections the street provides compared to parallel streets. People living with disabilities emphasize the importance of having safe and connected walking and biking routes on Iris Avenue to connect them to everyday needs, like shops, grocery stores, and high frequency transit. People who commute on Iris Avenue want a connection on Iris to support their current travel or to be prepared for completion of the CO 119 Safety, Mobility and Bikeway Project. “This arterial is vital to become a transit and multimodal city. But for users to use this corridor it must feel safe for all roadway users. Speeds should be reduced, and protection should be put in place for bicycles and pedestrians and safe transit accessibility for the less mobile.” Palo Park commuter Most want to keep as many of the existing public street trees for the beauty and shade they provide regardless of their other priorities for Iris Avenue. “First and foremost, preserve the existing tree canopy. The trees are big and beautiful and add so much personality and charm to Iris. None of the proposed improvements are worth losing any of the trees over.” North Boulder neighbor who lives along Iris Many are concerned about travel time changes any alternative would introduce. “It was unclear from the information what impact Alternatives A&B have on vehicular travel time on Iris. To me, these seem like reasonable, balanced alternatives AS LONG AS vehicular travel times aren't significantly impacted. I'm ok with some minimal additional delays during peak times in order to have safer routes for cyclists and to preserve trees. However, if travel Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 32 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 44 of 111 time is significantly delayed on one of the only continuous east-west vehicular routes in this part of the city, I would have a different opinion and would support Alternatives C or D.” A respondent who drives and bikes Iris to work and for shopping The majority of questionnaire respondents (56.6%) live in North Boulder. These respondents primarily drive on Iris and prioritize vehicle travel time. The next most common respondents were bicyclists (15.6%). These bicyclists primarily live in North and Central Boulder and prioritize biking crossing safety and comfort. The most common reason all respondents gave for traveling on Iris Avenue is for shopping and errands, followed by reaching recreation or entertainment, living along Iris Avenue or nearby, to travel between communities, reaching healthcare, and commuting to work. When asked for their priorities for designing Iris Avenue, questionnaire respondents’ answers grouped into three distinct tiers (Table 3). Table 3: Questionnaire respondents' project priorities Tier 1 (greater than 100 selections) Tier 2 (20 to 100 selections) Tier 3 (less than 20 selections) Vehicle Travel Time Along the Corridor Disaster Emergency Response Stormwater Drainage Crash Reduction Time and Cost to Design and Implement Right-of-Way Acquisition Biking Comfort Vehicle Turning Movements Utility Relocation Pedestrian Crossing Safety and Comfort Walking Comfort Bike Crossing Safety and Comfort Day-to-Day Emergency Response Vehicle Speed Moderation Transit Accessibility Preserving Existing Trees Opportunity for Protected Intersection Elements Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 33 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 45 of 111 The Community and Environmental Assessment Process (CEAP) is Boulder’s formal review process that assesses the potential impacts of capital improvement projects to help select the best conceptual design alternative. The CEAP uses the established CEAP goals assessment, checklist and checklist questions, project-specific evaluation criteria and community input to identify a recommended alternative. Goals Assessment 1. Using the BVCP and department master plans, describe the primary city goals and benefits that the project will help to achieve: a. Community Sustainability Goals: How does the project improve the quality of economic, environmental and social health with future generations in mind? The Iris Avenue project helps the city achieve its: • Social health goals by providing an all ages and abilities corridor with safer and more comfortable transportation options no matter how someone chooses to travel. • Economic goals by the provision of and investment in infrastructure that attracts, sustains and retains businesses, entrepreneurs, workers, and customers, and by ensuring safe and comfortable connections to destinations along the corridor and on the broader city transportation network. • Environmental goals by providing safe and comfortable multimodal transportation options which can reduce vehicle use and vehicle miles traveled and thus reduce the use of non-renewable energy resources and greenhouse gas emissions. These changes can also protect water and air quality through utilization of existing infrastructure, by preserving existing public street trees, and through the reduction of mobile source emissions. b. BVCP Goals related to: • Community Design: o Policies: 2.03 Compact Development Pattern, 2.38 Importance of Urban Canopy, Street Trees & Streetscapes: The project supports these policies by enabling safe travel by biking and walking which supports a more compact development pattern, and by working within the current roadway to avoid a significant number of tree removals. • Facilities and Services: o Policy: 8.13 Support for Community Facilities: The project supports this policy by safely connecting City and County community facilities throughout the corridor. o Policies: 2.38 Importance of Urban Canopy, Street Trees & Streetscapes, 3.22 Floodplain Management: The project supports these policies by working within the current roadway to avoid a significant number of tree removals and by avoiding floodplain impacts. • Economy: Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 34 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 46 of 111 o Policy: 5.03 Diverse Mix of Uses and Business Types: The project supports this policy by improving connections to and from the diverse uses and businesses at the corridor’s “bookends” and surrounding residential uses. • Transportation: o Policies: 2.25 Improve Mobility Grid & Connections, 2.26 Trail Corridors/Linkages, and all the Transportation section policies 6.01-6.24.: The project supports these policies by improving safety and connectivity between the roadway and trail networks for all who travel along and across Iris Avenue regardless of transportation mode. It also connects planned regional trails on the east end of the corridor to neighborhood trail connections on the west end. This project provides the largest benefits to the BVCP goals related to transportation. • Housing: The Iris Avenue project does not directly support any of the housing goals. Enhanced multimodal safety and connectivity supports modal choice, and thereby, access to the diversity of housing types envisioned in the BVCP. • Social Concerns and Human Services: o Policy: 8.07 Safety: The project supports this policy by improving safety for all roadway users which reduces the need for day-to-day emergency response, while also maintaining four vehicle lanes for use during a disaster emergency response. c. Describe any regional goals (potential benefits or impacts to regional systems or plans?) In 2021, the Boulder Valley Comprehensive Plan affirmed the city’s long-standing approach to creating an all-mode transportation system that provides safe connections for everyone, no matter how they travel. 2. Is this project referenced in a master plan, subcommunity or area plan? If so, what is the context in terms of goals, objectives, larger system plans, etc.? If not, why not? In 2019, the Transportation Master Plan (TMP) identified a corridor study of Iris Avenue as a future action item. In 2019, the Low Stress Walk and Bike Network Plan recommended enhancing separation and protection between vehicle and bicycle lanes on Iris Avenue, alongside improving pedestrian facilities in critical areas. These recommendations were made by Iris Avenue having more than three vehicle lanes, a posted speed limit of 35 miles per hour, and an average daily traffic volume exceeding 6,000 vehicles. In 2022, the Safe Streets Report (SSR) highlighted significant traffic safety concerns in Boulder. Between 2018 and 2020, there were 14,500 crashes involving 150 serious injuries. Arterial streets like Iris Avenue accounted for 67% of these severe crashes, with specific hotspots identified at intersections such as 28th Street, Folsom/26th Street, and Broadway. The SSR also identified crash types that disproportionately affected vulnerable groups like young people and seniors. Data from the Iris Avenue project revealed that one in ten pedestrians or cyclists on Iris Avenue each day were young, elderly, or disabled. Community Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 35 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 47 of 111 feedback consistently expressed concerns about safety while walking or biking on Iris, despite the significant number of daily users. The 2023 – 2027 Vision Zero Action Plan (VZAP) identified the High Risk Network (HRN), where 7% of the city’s street network have nearly half of all severe crashes. Iris Avenue, from 19th Street to 28th Street is on the HRN. The VZAP identified reactive and proactive actions to manage risk and mitigate crashes, including prioritizing work on the HRN and Core Arterial Network (CAN). Iris Avenue is a priority CAN corridor. 3. Will this project be in conflict with the goals or policies in any departmental master plan and what are the trade-offs among city policies and goals in the proposed project alternative? (e.g. higher financial investment to gain better long-term services or fewer environmental impacts) No. 4. List other city projects in the project area that are listed in a departmental master plan or the CIP. • 19th Street Multimodal Improvements project: Norwood to Sumac avenues • 28th Street Improvements Project: Iris Avenue to Canyon Boulevard • Folsom Street Multimodal Improvements Project: Pine Street to Colorado Avenue • Fourmile Canyon Creek Flood Mitigation: 19th Street Underpass • Neighborhood Green Street: 15th Street and Iris Avenue Pedestrian Crossing Improvements • Sumac Avenue Improvements: Broadway to 19th Street • US36/28th Street Multi-Use Path Project: Fourmile Canyon Creek to Jay Road 5. What are the major city, state, and federal standards that will apply to the proposed project? How will the project exceed city, state, or federal standards and regulations (e.g. environmental, health, safety, or transportation standards)? The City of Boulder Transportation Master Plan and Low Stress Walk and Bike Network Plan recommend greater separation and protection between vehicle and bicycle lanes on Iris Avenue and a need for pedestrian improvements in key areas along the corridor. The Core Arterial Network was reaffirmed as a council priority in April 2024. The Vision Zero Action Plan identifies Iris Avenue as part of the High Risk Network. Federal Highway Administration (FHWA) guidance states that lane repurposing is typically implemented on roadways with an average daily traffic of 25,000 vehicles and does not recommend removing a bicycle facility where one exists. FHWA recognizes lane repurposing, or road diets, as a street width reduction that can calm traffic speeds. All new transportation infrastructure constructed as part of the project will meet or exceed the updated City of Boulder Design and Construction Standards. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 36 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 48 of 111 6. Are there cumulative impacts to any resources from this and other projects that need to be recognized and mitigated? No, this project fits within current roadway requiring no further hardscape, maintaining the existing tree canopy and mitigating negative effects on natural resources. This project also does not require additional maintenance and retains current capacity for services such as police and fire. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 37 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 49 of 111 CEAP Checklist The CEAP checklist evaluates potential social and environmental impacts to guide analysis and comparison of the conceptual alternatives. This provides an opportunity to balance multiple community goals in the design of a capital project by assessing consistency with policies outlined in citywide and departmental plans, like the Boulder Valley Comprehensive Plan, Transportation Master Plan, and Vision Zero Action Plan. The CEAP checklist rates each alternative (+) Positive effect, (-) Negative effect, and (0) No effect. The results of the CEAP checklist evaluation can be found in Attachment B. Only CEAP checklist criteria that identified a positive or negative effect for an alternative are shown. Checklist Questions CEAP checklist questions are a supplement to the CEAP checklist. Only checklist lines that indicated a positive or negative effect provide more information in the corresponding checklist question. Attachment C provides the detailed responses to the checklist evaluation questions. Checklist Criteria Summary The CEAP checklist evaluation resulted in Alternatives A and B having a net positive effect and Alternatives C and D having a net negative effect. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 38 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 50 of 111 Natural Features Alternatives C and D have negative effects on natural features because they widen the roadway, increase hardscape (the amount of concrete) and remove mature trees. Mature trees may provide habitat – but this has not been evaluated for the project. It is assumed that by removing trees the potential for providing habitat is also removed. Alternatives A and B do not widen the roadway and so do not increase hardscape (or amount of concrete), maintain existing public street trees, including mature trees, and the wildlife and habitat services they may provide. Attachment D: Table of Mature Trees provides more information on the number of mature trees within the project area and those impacted by each of the four alternatives. Riparian Areas/Floodplains Alternatives A and B have no effect on Riparian Areas because they do not encroach on a riparian corridor. Alternatives C and D have a negative effect on Riparian Areas because they encroach on the Twomile Canyon Creek. No alternative is expected to cause a rise in the floodplain and no alternative is expected to remove any property from the floodplain. Attachment E: Floodplain Memo provides more information. Geology and Soils Alternatives A and B have no effect on geology and soils because they can be implemented within the existing roadway width. Alternatives C and D have a negative effect on geology and soils because they widen the roadway and so create a change in fill material. Water Quality Alternatives A and B have no effect on water quality because they can be implemented within the existing roadway and so do not require clearing and excavation, an increase in hardscape, or changes to site ground features, storm drainage, or vegetation. Alternatives C and D widen the roadway and so require clearing and excavation and increase hardscape, site ground features, storm drainage needs, and public street tree removal. Water quality mitigation with permanent best management practices (BMPs) will be installed with either Alternative C or D, creating no effect on water quality. Air Quality Transportation research does not find vehicle lane repurposing results in increased emissions. Instead, the research finds traffic emissions reductions from congestion mitigation are not Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 39 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 51 of 111 guaranteed and demand-based emissions reduction strategies can be more effective,10 and a reduction in fine particulate emissions with multimodal improvements on a corridor.11 Therefore, all alternatives have a positive effect on air quality because they provide safer walking and bicycling options along the corridor, which can reduce mobile source emissions. Alternatives A and B provide a greater positive effect because they also provide space for protected intersection elements, shorter crossing distances, and opportunity for refuge islands at midblock crossings, creating safer and more comfortable crossings of Iris Avenue as well. Alternatives C and D only provide protected bike lanes and sidewalk improvements but no safer and more comfortable crossings, and so have a smaller positive effect on Air Quality than Alternatives A and B. Physiological Well-Being Alternatives A and B have no effect on physiological well-being as measured by exposure to excessive noise. Alternatives C and D have a negative effect on physiological well-being during construction, because they require significant tree removals, and after implementation by moving the existing curbs closer to adjacent properties, and so increase road noise for adjacent homes. Services Alternatives A and B have a net positive effect on services because they support current police and fire services and provide transportation improvements. Alternatives A and B repurpose vehicle lanes, introduce a center turn lane, and provide space for protected intersection elements. These design components moderate speeds and reduce crashes and the severity of crashes when they do occur, providing positive effects for transportation and for police and fire services by reducing the need to respond to day-to-day emergencies. The center turn lane provides dedicated space for turning vehicles and for police and fire response. Therefore, Alternatives A and B improve transportation by reducing the common corridor crash types and support police and fire services by providing dedicated space for emergency response vehicles. Alternatives C and D have no effect on transportation and the need for police and fire services because they maintain the current vehicle lanes available for emergency response and maintain the current need for day-to-day emergency response because they do not moderate vehicle speeds or reduce crashes. 10 https://www.sciencedirect.com/science/article/abs/pii/S1361920912000727 11 https://www.sciencedirect.com/science/article/abs/pii/S1361920914001254 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 40 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 52 of 111 Special Populations All alternatives have a positive effect for persons with disabilities, senior population, children and youth and sensitive populations, because they each provide improved sidewalks, protected bike lanes and Americans with Disabilities Act curb ramp compliance work. Alternatives A and B provide a greater positive effect than Alternatives C and D because they repurpose a vehicle lane. Repurposing a lane provides space for protected intersection elements at intersections, improved bus stops, and the potential for pedestrian refuge islands at midblock crossings, which reduce crossing distance for people walking and biking and reduces their exposure to vehicles. Economy Alternatives A and B have a positive effect on economy because they can be implemented within the existing curb-to-curb width and so utilize existing infrastructure. Alternatives C and D have a negative effect because they require roadway widening and so create new infrastructure. Project Specific Evaluation Criteria To recognize the project’s unique context and needs, the project team defined project-specific evaluation criteria. The project specific evaluation criteria provide more detailed evaluation than the considerations from which they were developed, and further compare and contrast the four alternatives from the CEAP checklist criteria. Evaluation Criteria Definitions Project specific evaluation criteria have five parts: 1. Definition provides the critical inputs to the score. 2. Methodology provides the method – qualitative or quantitative or both – of scoring. 3. Methodology Rationale provides additional information on why the methodology was used. 4. Comparison Metric states whether the score is based on a comparison to other alternatives or to the existing condition. 5. Source/References provide backup data used in the methodology. Each alternative was rated using the following scale: Scoring: -5 significantly poor/worse, -3 poor/worse -1 slightly poor/worse, 0 neutral, 1 slightly good/better, 3 good/better, 5 significantly good/better. Figure 17: Project Specific Evaluation Criteria Rating Legend Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 41 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 53 of 111 The detailed results of evaluating each alternative using the project specific evaluation criteria is shown in Attachment C. Traffic Safety Vehicle speed moderation 1. Definition: Reduction in prevailing speed and/or speeding, achieved through: a. Reducing lane widths b. Reducing the number of lanes c. Providing Horizontal deflection/friction (including turns at intersections) d. Providing vertical/visual friction (trees, bike lane separation) 2. Methodology: A quantitative and qualitative assessment of an alternative’s potential effect on speeds resulting from the inclusion of one, or a combination, of the definition elements. 3. Methodology Rationale: Many factors influence how fast people drive. The project team considered the way the road is designed today, and scored the alternatives based on how each alternative alters the current design with respect to vehicle speed moderation. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a. Federal Highway Administration Road Diet Information Guide b. Lower Citywide Speed Limits and Design Changes | FHWA (dot.gov) c. lane-reconfiguration-guidelines-final-with-attachments-jan-2020.pdf (lacity.gov) d. Speed Reduction Mechanisms | National Association of City Transportation Officials (nacto.org) e. Reducing Turn Speeds and Mitigating Conflicts | National Association of City Transportation Officials (nacto.org) f. Design Speed | National Association of City Transportation Officials (nacto.org) g. Federal Highway Administration Safe System Approach for Speed Management Crash reduction 1. Definition: Reduction in the number and severity of crashes, achieved through: a. Reduced number of conflict points b. Addition of turn lanes c. Separation of vulnerable road users d. Reduced speeds (based on vehicle speed moderation criteria) e. Motorist-bicyclist interaction and expectation 2. Methodology: A quantitative and qualitative assessment of an alternative’s potential effect on the number and severity of crashes resulting from the inclusion of one, or a combination, of the definition elements, and the difficulty or intuitive nature for users of a bike facility. 3. Methodology Rationale: Proven safety countermeasures and crash reduction factors were evaluated where possible. In addition, the project team evaluated potential for crash reduction based on a Safe Systems Approach and the City’s Vision Zero Action Plan, where speeds, conflict points, two-way bike facilities, and other Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 42 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 54 of 111 factors that don’t have available established predictive safety outcomes, can be considered. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a. NACTO Urban Street Design Guide: Design Speed Design Speed | National Association of City Transportation Officials (nacto.org) b. 3-5mph reduction FHWA Guide: https://highways.dot.gov/sites/fhwa.dot.gov/files/2022-06/rdig.pdf c. 1-2mph reduction LRRB/MnDOT study: https://www.lrrb.org/pdf/200625.pdf d. Crash Modification Factors (CMFs) / Road Diet i. Applicable CMFs are listed below: ii. CMF ID: 5553 - CONVERTING FOUR-LANE ROADWAYS TO THREE- LANE ROADWAYS WITH CENTER TURN LANE (ROAD DIET). Shows a 25% decrease in total crashes iii. CMF ID: 2841 - CONVERTING FOUR-LANE ROADWAYS TO THREE- LANE ROADWAYS WITH CENTER TURN LANE (ROAD DIET). Different study. Shows a 47% decrease in total crashes iv. CMF ID: 11128 - ROAD DIET (CONVERT 4-LANE UNDIVIDED ROAD TO 2-LANES PLUS TURNING LANE). Shows a 38% decrease in total crashes a. CMF ID: 11301 - CONVERT TRADITIONAL BIKE LANE TO SBL WITH A BLEND OF FLEXI-POST AND OTHER VERTICAL ELEMENTS. Shows a 36% decrease in vehicle-to-bicycle crashes e. Proven Safety Countermeasures | FHWA (dot.gov) f. What Is a Safe System Approach? | US Department of Transportation g. Vision Zero Action Plan | City of Boulder (bouldercolorado.gov) Evaluation Results Figure 18: Safety Project Specific Evaluation Results Vehicle speed moderation Alternatives A and B reconfigure the roadway with vehicle lane repurposing between 13th Street and Folsom/26th Street from four vehicle lanes to two vehicle lanes, which moderates vehicle speeds up to five miles per hour. Alternatives C and D maintain four vehicle lanes and so maintain current vehicle speeds. Existing conditions data shows most drivers are speeding on Iris Avenue between Broadway and Folsom/26th Street. Vehicle speeding leads to numerous safety concerns and increases the severity of crashes involving vehicles. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 43 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 55 of 111 All alternatives include protected bike lanes which provide vertical or visual friction. These elements can moderate vehicle speeds up to two miles per hour. Crash reduction Alternatives A and B reconfigure the roadway with vehicle lane repurposing and introduce a center turn lane to provide more space for protected intersection elements and so reduce crashes by 25% - 50%. These design elements reduce the corridor’s common crash types, rear ends and approach turn crashes, VZAP common crash types of left turn crashes, right turn crashes, and pedestrian/bicyclist crashes while crossing the street, and reduce the severity of crashes when they do occur through reduction of vehicle speeds. Corridor Common Crash Types o The center turn lane:  Removes turning vehicles from the vehicle travel lane, reducing the potential for rear end crashes.  Gives drivers a safe place to wait for a gap in traffic to complete their turn, reducing the potential for approach turn crashes. VZAP Common Crash Types • Protected intersection elements: o Physically separates people walking, biking, and rolling from vehicles up to and through the intersection. o Intersection tightening and corner islands make it easier for people walking, biking, and rolling to see and be seen by drivers. Severity of Crashes • Vehicle lane repurposing moderate vehicle speeds up to five miles per hour. • Intersection tightening and corner islands slow turning vehicles which make turns and crossings safer. Alternatives C and D do not reconfigure the roadway with vehicle lane repurposing, do not introduce a center turn lane, and provide less space for protected intersection elements than Alternatives A and B and so do not reduce the corridor’s common crash types, VZAP common crash types or reduce the severity of crashes when they do occur because they do not moderate vehicle speeds. All alternatives include protected bike lanes which decrease vehicle-bicycle crashes by up to 35%. Note: Alternatives with two-way bike lanes will also include design features such as protected intersection elements, raised crossings, two-way signs and markings, striping and signal changes that separate vehicle and bike movements at intersections, accounting for speed of vehicles and bicycles, to be detailed in the final design phase to reduce potential conflicts between bicyclists and drivers at side streets and driveways. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 44 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 56 of 111 Transportation Operations Corridor vehicle travel time 1. Definition: The change in the median and 95th percentile travel time to drive the corridor from end-to-end between Broadway and 28th Street based on ten VISSIM microsimulation traffic modeling runs for each peak period for eastbound and westbound traffic roadway capacity with NACTO guidelines recommended signal control operations for one-way and two-way protected bike lanes. a) Traffic operations – AM Peak b) Traffic operations – PM Peak 2. Methodology: Quantitative assessment of travel time measured as an output of VISSIM microsimulation traffic modeling. 3. Methodology Rationale: The 2019 TMP targets maintaining 1994 levels of travel times on Boulder arterial streets, as well as improving travel time reliability and predictability. The TMP found that, for the drive time study corridors, average travel times have increased by 1 minute, or 15%, since baseline year. A travel time increase of up to 15% is therefore rated as acceptable for Iris Avenue with additional 15 point increments resulting in successively lower ratings. Any travel time exceeding a 15% increase is further evaluated for acceptability. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: b. 2020 Boulder Transportation Report on Progress c. LA DOT Lane Reconfiguration Guidelines d. Synchro and Vissim Traffic existing and proposed models developed for project Vehicle turning movements 1. Definition: Improve safety and efficiency of access to and from adjacent properties and non-signalized streets based on ten VISSIM microsimulation traffic modeling runs for each peak period for eastbound and westbound traffic roadway capacity with NACTO guidelines recommended signal control operations for one-way and two-way protected bike lanes. a. Number of turns expected from a through lane b. Likelihood of blocked driveways and accesses due to queued traffic 2. Methodology: Quantitative analysis based on VISSIM microsimulation traffic modeling of the alternatives that evaluates the current number of vehicles that use through travel lanes to make turns. Traffic models assess the likelihood of accesses being blocked by queued traffic and the effect of platooned traffic on availability of gaps to make turns into and out of non-signalized side streets and driveways. 3. Methodology Rationale: Access to properties via dedicated turn lanes rather than through travel lanes improves user comfort and safety. This is balanced with the frequency and length of gaps in Iris Avenue traffic streams to facilitate turns out of side streets and driveways safely and without excess delay. The project team Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 45 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 57 of 111 evaluated the ability of each alternative to improve ease, comfort, and safety of access. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a. Access Management (Driveways) | FHWA (dot.gov) b. Access Management: Benefits of Access Management Brochure - FHWA Operations (dot.gov) a. Synchro and Vissim Traffic existing and proposed models developed for project Vehicular level of service 1. Definition: Provide a corridor that is easy to navigate for all modes as measured by change in Level of Service (LOS) of the corridors signalized intersections. 2. Methodology: Quantitative analysis of the relative change of how many vehicles can traverse the roadway during a given time period, based on ten VISSIM microsimulation traffic modeling runs for each peak period for eastbound and westbound traffic roadway capacity with NACTO guidelines recommended signal control operations for one-way and two-way protected bike lanes. 3. Methodology Rationale: Maintain existing LOS and delay is neutral; positive or negative scores depending on changes to level of service or delay. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a) City of Boulder Design and Construction Standards b) https://t4america.org/community-connectors/what-they-mean/level-of- service/ c) https://ladot.lacity.gov/sites/default/files/2022-08/lane-reconfiguration- guidelines-final-with-attachments-jan-2020.pdf d) NACTO Urban Bikeway Design Guide e) Synchro and Vissim Traffic existing and proposed models developed for project Day-to-day emergency response 1. Definition: Provide space for emergency response vehicles to move through traffic. 2. Methodology: Qualitative assessment of right-of-way available for private vehicles to move aside and right-of-way available for emergency response vehicles to operate. 3. Methodology Rationale: Assessed by City of Boulder Fire and Police departments for whether the alternative changes current day-to-day emergency response. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a) Methodology based on discussions with City of Boulder Fire Rescue and Police Department, and Boulder County Office of Disaster Management b) FHWA – Road Diet Emergency Response Times c) NACTO – Best Practices Emergency Access in Healthy Streets Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 46 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 58 of 111 Disaster Emergency Response 1. Definition: Provide space for private vehicles to evacuate during a disaster and for disaster emergency response vehicles to move through traffic. 2. Methodology: Quantitative analysis of widths of emergency response vehicles and number of travel lanes available, and professional judgment. Methodology Rationale: The team worked with the Office of Disaster Management (ODM) for the City of Boulder and Boulder County, and the city’s Boulder-Fire Rescue (BFRD) and Police (BPD) departments, to evaluate the protected bike lane design widths, the presence, or not, of center two-way left-turn lanes, and the number of through lanes available for disaster emergency response. Under a disaster emergency response, a minimum of two continuous evacuation lanes and one emergency vehicle lane are desired. During a disaster emergency response, a center two-way left-turn lane can be used for personal vehicle travel and a two-way protected bike lane is wide enough to accommodate disaster emergency response vehicles. The project team will continue to coordinate with BFRD, BPD, and ODM on roadway design features for the use of the center turn lane as a second eastbound evacuation lane during the final, or detailed, design phase. 3. Comparison Metric: Alternatives compared to existing conditions 4. Source/References: d) How Cycle Paths Can Be Used by Emergency Services e) Methodology based on discussions with City of Boulder Fire Department. f) FHWA – Road Diet Emergency Response Times g) NACTO – Best Practices Emergency Access in Healthy Streets Evaluation Results Figure 19: Transportation Operations Project Specific Evaluation Criteria Results Corridor vehicle travel time All alternatives increase current travel time. These increases vary depending on the time of day and direction of travel. Travel time increases because each alternative includes FHWA recognized proven safety countermeasures and include traffic signal changes that separate vehicle and pedestrian/bike movements at intersections in accordance with industry best practices for protected bike lanes. Average of potential AM and PM peak travel time increases: • Alternative A • Average trip: 16 seconds to 1 minute 03 seconds • Most trips (95th Percentile): 15 seconds to 01 minute 04 seconds Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 47 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 59 of 111 • Slowest trips (5% of trips): 39 seconds to 01 minute 42 seconds • Alternative B • Average trip: 03 to 46 seconds • Most trips (95th Percentile): 02 to 58 seconds • Slowest trips (5% of trips): 01 second to 02 minutes 09 seconds • Alternative C • Average trip: 01 to 17 seconds • Most trips (95th Percentile): 02 to 27 seconds • Slowest trips (5% of trips): No change from today to 01 minute 08 seconds • Alternative D • Average trip: 01 to 25 seconds • Most trips (95th Percentile): 03 to 36 seconds • Slowest trips (5% of trips): 13 seconds to 01 minute 10 seconds Vehicle turning movements All alternatives maintain the current level of vehicle turning movements at side streets and driveways. Alternatives A and B reconfigure the roadway with vehicle lane repurposing between 13th Street and Folsom/26th Street from four vehicle lanes to two vehicle lanes, and introduce a center turn lane. The center turn lane provides a safe waiting area to turn left into a side street or driveway and provides an opportunity to make a two-stage left turn out of a side street or driveway. These turning movements offset the traffic model projected queued traffic and the effect of platooned traffic on the availability of gaps in traffic to turn into and out of side streets and driveways. Alternatives C and D maintain four vehicle lanes and so supports the current and modeled number of vehicles that use through travel lanes to make turns onto and out of side streets and driveways. Impacts to the vehicular level of service All alternatives reduce vehicular level of service. Alternative A reduces vehicular level of service by two levels due to vehicle lane repurposing and the implementation of traffic signal changes to separate turning vehicles from people walking and biking at major intersections. Alternative B reduces vehicular level of service by one level due to vehicle lane repurposing and the implementation of traffic signal changes to separate turning vehicles from people walking and biking at major intersections on the north side of the street. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 48 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 60 of 111 Alternative C reduces vehicular level of service by one level due to implementation of traffic signal changes to separate turning vehicles from people walking and biking at major intersections. Alternative D reduces vehicular level of service by one level due to implementation of traffic signal changes to separate turning vehicles from people walking and biking at major intersections on the north side of the street. Day-to-day emergency response Alternatives A and B improve day-to-day emergency response because they introduce a center turn lane which provides space for motorists to pull over and it provides dedicated space for day-to-day emergency response and stopping (Figure 20). Figure 20 Day-to-Day Emergency Response Vehicle Operations Alternatives C and D reduce day-to-day emergency response because they do not provide space for motorists to pull over because the bike lane protection will block vehicles from using the bike lane, and emergency vehicles must navigate the corridor with traffic for day-to-day emergency response. Disaster Emergency Response Alternative A reduces disaster emergency response because it reduces the number of eastbound lanes, which supports evacuating vehicles, and reduces the number of westbound lanes, which support personal and emergency response vehicles traveling to a disaster area. Alternative B supports the current level of disaster emergency response because it provides the same number of eastbound and westbound lanes as today. The eastbound vehicle lane and Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 49 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 61 of 111 center turn lane provide the same number of lanes as today for evacuating vehicles. The westbound vehicle lane and the two-way protected bike lane provide the same number of lanes for personal and emergency response vehicles traveling to a disaster area. Roadway design features for the use of the center turn lane as a second eastbound evacuation lane will be coordinated with ODM, BPD, and BFRD during final design (Figure 21). Figure 21 Disaster Emergency Response Vehicle Operations Alternative C supports the current level of disaster emergency response because it provides the same number of eastbound and westbound lanes as today. Alternative D improves the current level of disaster emergency response because it has the same number of eastbound and westbound lanes as today and the two-way protected bike lane provides dedicated space for emergency response vehicles for the majority of the corridor with the exception of approximately one block where the two-way bike lane becomes a multi-use path. Safe and Comfortable Connections Walking comfort 1. Definition: Provide a pedestrian route that can reduce the City of Boulder Low Stress Walk and Bike Network Plan pedestrian stress factors and scores a 1 or 2 on the Oregon Department of Transportation (DOT) Level of Traffic Stress (LTS) scale. 2. Methodology: A qualitative and quantitative evaluation according to the city’s Low Stress Walk and Bike Network Plan and to the Oregon DOT LTS metric. 3. Methodology Rationale: The Boulder Low Stress Network should include Iris Avenue. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 50 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 62 of 111 a) Analysis conducted based on Level of Traffic Stress methodologies here: Analysis Procedures Manual Chapters 1-4 (oregon.gov) b) The Low-Stress Walk and Bike Network Plan | City of Boulder (bouldercolorado.gov) Biking comfort 1. Definition: Provide a bike route that implements the City of Boulder Low Stress Walk and Bike Network Plan recommendation and scores a 1 or 2 on the Oregon Department of Transportation (DOT) Level of Traffic Stress (LTS) scale. 2. Methodology: A qualitative and quantitative evaluation according to the city’s Low Stress Walk and Bike Network Plan and to the Oregon DOT LTS metric. 3. Methodology Rationale: The Boulder Low Stress Walk and Bike Network Plan identifies Iris Avenue as part of the low stress network. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a) Analysis conducted based on Level of Traffic Stress methodologies here: Analysis Procedures Manual Chapters 1-4 (oregon.gov) b) The Low-Stress Walk and Bike Network Plan | City of Boulder (bouldercolorado.gov) Opportunity for protected intersection elements 1. Definition: Evaluate the extent protected intersection elements can be incorporated into signalized and unsignalized intersections. 2. Methodology: A qualitative and quantitative evaluation of the amount of space available for protected intersection elements. 3. Methodology Rationale: Protected intersections slow vehicle speeds, increase visibility and reduce crossing distances for people walking, biking, and rolling, and provide dedicated paths for bikes through the intersection. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a. Don’t Give Up at the Intersection, NACTO Crossing safety & comfort 1. Definition: Evaluate how well space for safer roadway crossings, like pedestrian refuge islands, can be provided. 2. Methodology: A qualitative and quantitative evaluation of the amount of space available for pedestrian refuge islands. 3. Methodology Rationale: The Boulder Low Stress Walk and Bike Network Plan identifies Iris Avenue as part of the low stress network. 4. Comparison Metric: Alternatives compared to existing conditions 5. Source/References: a. Medians and Pedestrian Refuge Islands in Urban and Suburban Areas, FHWA Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 51 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 63 of 111 Evaluation Results Figure 22: Safe and Comfortable Connections Project Specific Evaluation Criteria Results Walking comfort Alternative A provides safer and more comfortable walking facilities because the one-way protected bike lanes provide greater separation between the sidewalk and vehicle lanes, and it provides vehicle lane repurposing, which slows vehicle speeds. Alternative B provides safer and more comfortable walking facilities on the north side of the street because the two-way protected bike lane provides greater separation between the sidewalk and westbound vehicle lanes and reduces the amount of space between the south side sidewalk and eastbound vehicle lanes. The alternative provides vehicle lane repurposing, which slows vehicle speeds improving walking and crossing comfort for all. Alternative C provides safer and more comfortable walking facilities because the one-way protected bike lanes provide greater separation from vehicle lanes. However, Alternative C maintains current vehicle lanes and therefore current vehicle speeds. Alternative D reduces walking comfort and safety because any benefit of greater separation between the sidewalk and westbound vehicle lanes the two-way protected bike lane on the north side of the street provides is overwhelmed by impacts from maintaining four vehicle lanes and attaching sidewalk on the south side of the street. Maintaining current vehicle lanes requires the two-way bike lane to convert to a multi-use-path between Iris Court and 19th Street due to right-of-way constraints and maintains current vehicle speeds. The two-way protected bike lane on the north side of the street results in attached sidewalk on the south side of the street. Biking comfort Alternatives A and B provide safer and more comfortable biking facilities by providing protected bike lanes and vehicle lane repurposing, which slows vehicle speeds. Alternatives C and D provide safer and more comfortable biking facilities by providing protected bike lanes, but they maintain current vehicle lanes and so current vehicle speeds. Alternative B and D include a two-way protected bike facility that supports all ages and abilities, safer bike passing, and shortened crossing distances. Locating the two-way protected bike lane on the north side of the street improves safety due to fewer conflicts with driveways and side streets than the south side allowing for increased investment at each conflict. The two-way protected bike facility creates the space to enable key safety features like protected Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 52 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 64 of 111 intersection elements and will utilize two-way signs and markings, striping and signal changes that separate vehicle and bike movements at signalized intersections to improve biking safety. Opportunity for protected intersection elements Alternatives A and B reconfigure the roadway with lane repurposing and so provide more space for protected intersection elements. Protected intersection elements reduce VZAP common crash types of left turn crashes, right turn crashes, and pedestrian/bicyclist crashes while crossing the street, and reduce the severity of crashes when they do occur through reduction of vehicle speeds. Alternative C and D provide less space for protected intersection elements and so are less effective at reducing VZAP common crash types or reducing severity of crashes when they do occur. Crossing safety & comfort Alternatives A and B provide greater crossing safety and comfort because they reconfigure the roadway with lane repurposing and so shorten crossing distance and amount of time vulnerable road users are exposed to vehicle traffic and incorporate traffic signal changes to separate turning vehicles from people walking and biking at major intersections. Alternatives C and D provide some crossing safety and comfort improvement though they maintain current crossing distances because they incorporate traffic signal changes to separate turning vehicles from people walking and biking at major intersections. Implementation Feasibility The project team considered the following engineering constraints carefully. Note that at the current phase of the project (concept development) these scores utilize assumptions that are based on industry standards or best practice. Future phases of the project, like final design, may discover information that changes the scoring or the conceptual design. The project team finds this risk is generally applicable to all alternatives equally and therefore advances these criteria. Time to design and implement 1. Definition: A measure of the time and effort needed to implement the alternative as well as other factors that could complicate implementation, like necessary permits. 2. Methodology: Professional judgment of risks to the project including Right-of-Way needs, floodplain permitting, traffic control and phasing. 3. Methodology Rationale: Preliminary estimates for permitting, right-of-way acquisition, and phasing based on professional experience implementing similar alternatives. 4. Comparison Metric: Alternatives compared to each other 5. Source/References: Recently completed comparable capital improvements projects. Maintenance 1. Definition: A measure of added maintenance needs for transportation infrastructure, snow and ice response and street sweeping. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 53 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 65 of 111 2. Methodology: Qualitative analysis of additional labor and equipment required for snow and ice response and street sweeping, and long term maintenance and material replacement for added infrastructure. 3. Methodology Rationale: The team collectively determined a rating for known risk factors for each alternative. 4. Comparison Metric: Alternatives compared to each other 5. Source/References: Discussions with City of Boulder Transportation & Mobility Maintenance department. Right-of-Way property acquisition 1. Definition: Analysis of the number and size of permanent and temporary construction easements needed. 2. Methodology: Quantitative measure of the number and size of required permanent and temporary construction easements. Qualitative factors may be applied for impacts in difficult locations (such as near front doors or that would make a driveway unusable). 3. Methodology Rationale: Minimal impacts to adjacent projects is a goal of the Iris Avenue project. The project team seeks to minimize impacts by adjusting designs and looking for ways to accommodate an alternative within the existing right-of- way. 4. Comparison Metric: Alternatives compared to each other 5. Source/References: a. Alternative maps b. Right-of-way survey c. Field walk data Utility relocation and storm water drainage 1. Definition: Analysis of the number and type of storm drainage infrastructure such as inlets, pipes, and manholes, and utility impacts, such as storm water and sanitary sewer, Xcel electric and gas, and telecom. 2. Methodology: Quantitative analysis counts impacted ground level utility features and counts drainage impacts, such as inlets, manholes and length of pipe. These counts represent utility and stormwater conflicts, noting surface utility impacts are easily counted, but underground utility needs can be difficult to estimate. 3. Methodology Rationale: Drainage and utility impacts can be incredibly costly and greatly impact construction duration. The more underground work is needed, the more cost and schedule to implement will be increased. 4. Comparison Metric: Alternatives compared to each other. 5. Source/References: a. Alternative maps b. Existing storm drainage geospatial layers c. Field walk data Implementation Cost 1. Definition: Order of magnitude engineering cost estimates of construction. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 54 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 66 of 111 2. Methodology: Quantitative, measured using a scale of orders of magnitude for comparison purposes only. 3. Methodology Rationale: Cost to implement estimates are developed for each alternative and include right-of-way, utility and stormwater relocation costs, costs of tree removal, and high level construction cost estimates. Costs do not consider additional engineering or construction management and oversight as these costs would be similar for all alternatives. Full cost estimates will not be developed until later in the design process when more detailed design is completed. 4. Comparison Metric: Alternatives compared to each other 5. Source/References: Recently completed similar project cost estimates. Sustaining the Tree Canopy Preserves Existing Public Street Trees 1. Definition: A measure of required public tree removals minus the estimated potential to replant trees. 2. Methodology: Quantitative analysis of net public tree removals (trees removed less replanted trees) using the City of Boulder Forestry Department tree inventory developed for the Iris Avenue project. 3. Methodology Rationale: The City of Boulder Forestry Department Urban Forestry Strategic Plan and supporting Boulder Valley Comprehensive Plan policies (BVCP 2.38 Importance of Urban Canopy, Street Trees and Streetscapes, and BVCP 3.12 Urban Forests), identify the urban forest, public street trees and tree canopy as important. 4. Comparison Metric: Alternatives compared to existing conditions. 5. Source/References: a) City of Boulder Urban Forestry Strategic Plan a) Boulder Valley Comprehensive Plan (BVCP) i. BVCP 2.38 Recognizes the Importance of Urban Canopy, Street Trees and Streetscapes ii. BVCP 3.12 Urban Forests Evaluation Results Figure 23 Sustaining the Tree Canopy Project Specific Evaluation Criteria Results. Preserves Existing Public Street Trees Alternatives A and B can be implemented within the existing roadway and so require removal of 10 to 12 public streets tress to improve sightlines and provide space for potential tree replanting. Alternative C requires road widening to the north and south and so require removal of 69 to 75 public street tress. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 55 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 67 of 111 Alternative D requires road widening to the north only and so require removal of 43 to 50 public street trees. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 56 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 68 of 111 Project Specific Evaluation Summary Attachment F: Conceptual Alternatives with Project-Specific Evaluation Criteria Applied provides the full project specific evaluation criteria. Alternatives A and B reconfigure the roadway with vehicle lane repurposing, introduce center turn lanes and protected intersection elements, and include protected bike lanes and sidewalk improvements. Therefore, they should reduce crash types for vulnerable road users, reduce the common crash types the VZAP found occur on the High Risk Network (left turn crashes, right turn crashes, right on red crashes, and pedestrian crashes while crossing the street), and reduce the severity of crashes when they do occur through reduction of vehicle speeds. Alternatives A and B provide safer and more comfortable walking and biking facilities and crossings by providing separation from vehicles, provide more space for protected intersection elements, and shorten crossing distances. Alternatives C and D only include protected bike lanes and improved sidewalks. Therefore, they are less effective at decreasing the frequency and severity of crashes involving vulnerable road users and do not address the common crash types identified by the VZAP or reduce vehicle speeds to reduce crash severity. Alternative C and D do not provide safer crossings for people walking and biking than exist today. Alternative B and D include a two-way protected bike facility which may be less familiar for bicyclists to use and require drivers to look for cyclists traveling in both directions. These conflicts can be minimized by locating the two-way protected bike lane on the north side of the Iris Avenue, which has significantly fewer conflicts with driveways and side streets, and through other mitigations like signage and pavement markings. Alternatives A and B can achieve their safety benefits without widening the roadway and so are more easily implemented because they require no permanent right-of-way easements, require few public street tree removals, storm water drainage impacts and utility relocations, and take less time and cost to implement. Alternatives C and D require roadway widening and so require permanent right-of-way easements, significant public street tree removals, storm water drainage impacts and utility relocations, and so cost more and take more time to implement to provide fewer safety benefits. Every alternative will have increased travel time, depending on the time of day and direction of travel. Travel time increases because each alternative includes FHWA recognized proven safety countermeasures that respond to community input and the common crash type findings of the Vision Zero Action Plan. All alternatives also assume signal changes to separate vehicle and bike movements in accordance with industry best practices for protected bike lanes. This assumption contributes to end-to-end vehicle travel time increases and changes to intersection level of service under all alternatives. Across all alternatives, the largest increases to travel times by percentile are as follows: up to 1 minute 03 seconds for the average trip (Alternative A), up to 01 minute and 04 seconds for Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 57 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 69 of 111 most trips (Alternative A), and up to 2 minutes 09 seconds for the slowest trip (Alternative B) (Table 4). About 30 to 60 seconds separate alternatives with three vehicle lanes (Alternatives A and B) and alternatives with four vehicle lanes (Alternatives C and D) due to Alternatives A and B including road reconfiguration between the bookends. Table 4:Travel time estimates for average, 95th percentile and maximum travel time, using a combined existing AM and PM peak travel times Potential Travel Time Increase Average Trip Most Trips (95th Percentile) Slowest Trip (Maximum) Alternative A 16 seconds to 1 minute 03 seconds 15 seconds to 1 minute 04 seconds 39 seconds to 1 minute 42 seconds Alternative B 03 to 46 seconds 02 to 58 seconds 01 second to 2 minutes 09 seconds Alternative C 01 to 17 seconds 02 to 27 seconds No change from today to 1 minute 08 seconds Alternative D 01 to 25 seconds 03 to 36 seconds 13 seconds to 1 minute 10 seconds Intersection level of service is reduced for all the alternatives due to vehicle lane repurposing (Alternatives A and B) and the implementation of protected turn phases and bicycle signals (all Alternatives). Alternatives B, C, and D change level of service by one level, and Alternative A by two levels. Vehicle queuing for eastbound and westbound vehicles at the 19th Street and Folsom/26th Street intersections increase for Alternatives A and B with maximum queues of 1,000 feet that clear during each intersection signal cycle. All alternatives increase left and right turn queues at these intersections due to the protected turn phasing for vehicles and bikes. Each alternative supports day-to-day emergency response and disaster emergency response. Center turn lanes in Alternatives A and B support day-to-day emergency response by providing a dedicated lane for emergency operations. Two-way protected bike lanes in Alternatives B and D are wide enough to accommodate emergency vehicles during a disaster scenario. Alternative B and D supports both day-to-day and disaster emergency response through the combined design components of vehicle travel lanes, center turn lanes and two-way protected bike lanes. Community Input on CEAP and Recommended Alternative – Summer 2024 Staff shared the CEAP evaluation and recommended alternative with the community for feedback in July and August 2024 at an in-person open house with 163 attendees and a virtual open house questionnaire which received 217 responses. The questionnaire focused on the alternatives evaluation and the recommended alternative. Of the 217 respondents, 78.4% primarily drive, 17.6% bike, 2.7% walk, and less than 1% ride transit Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 58 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 70 of 111 along or across Iris Avenue. The most selected secondary modes of travel along or across Iris Avenue were biking, walking, and driving in that order. The most selected reasons for traveling Iris Avenue for the virtual open house questionnaire respondents were: • For shopping/errands: 161 • To reach recreation or entertainment: 124 • I live along or nearby Iris Avenue: 113 • To travel between communities: 109 • To reach healthcare: 79 • To commute to work: 69 • To take children to school: 20 • Other: 9 • To take children to childcare: 8 • To attend school myself: 5 When asked if there is anything the project team needs to clarify about the alternatives evaluation, 62.7% of questionnaire respondents said “No” and 37.3% said “Yes.” For respondents who responded “Yes,” an open-ended question asked what could be clarified about the alternatives evaluation. The responses to this question were intended to ensure common questions were answered in the CEAP and presentations of the CEAP to TAB and City Council. The most common questions were about: • Transit, waste, and delivery operations o How will buses, trash, and delivery vehicles operate in the proposed roadway and what are the rules for private vehicles using the center turn lane to pass stopped vehicles? • Eastern end business access management o If access to the Safeway Shopping Center is changed, what are the detour routes? • Entering/exiting two-way bike facility across Broadway o Describe movements from north and south corners of west side of Broadway to the 2-way bike facility and vice versa • How project will address crash hot spots at bookends o If vehicle lane configuration is not changing at bookends, how will crashes be mitigated? • Vehicle turns across two-way bike traffic o For left and right turns from and to Iris Avenue, how will vehicles find gaps and see bicyclists coming from both directions in the two-way protected bike lane? • Signal operations to separate bike/vehicle movements o Clarify protected phasing at major intersections and considerations for higher speed of e-bikes Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 59 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 71 of 111 Respondents and in-person open house participants also had an opportunity to state their concerns about the project for staff to consider in future design phases. The most mentioned were: • Traffic congestion and vehicle travel time o Respondents indicate concern about increased traffic congestion and travel time with the implementation of Alternative B. • Project process o Some respondents are concerned that the project process was predetermined or did not consider a wide range of alternatives while others are concerned that the project will not move forward due to public opposition. • Design Complexity o Some respondents are concerned about the two-way protected bike lane on the north side of Iris Avenue, navigating to and from it by bike, or crossing it while driving. Other respondents are concerned about the center two-way left turn lane and using it to turn on and off Iris Avenue. • Neighborhood side streets o Respondents express concerns about traffic diversion from Iris Avenue, the speed of vehicles on neighborhood streets, and the safety of people walking and biking on those streets. • Bookend intersection safety o Respondents mention concerns about bookend intersections remaining unsafe or uncomfortable to travel through or across with the implementation of Alternative B. • Emergency Evacuation o Respondents state concerns about emergency evacuation of eastbound vehicles during a wildfire or other disaster. Questionnaire respondents and in-person open house participants were also asked what design elements they are most excited about as the project moves forward. Their responses are grouped into three tiers in Table 5. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 60 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 72 of 111 Table 5. Design elements questionnaire respondents are “most excited” about Tier 1 (70 or more selections) Tier 2 (40-59 selections) Tier 3 (fewer than 30 selections) Safer crossings Vehicle speed moderation Minimal right-of-way impacts Preservation of Tree Canopy Optimized Signal Operations Center turn lane End-to-end two way protected bike lane Minimal cost and time to implement Emergency response use Protected intersections Roadway reconfiguration Updated wayfinding Improved sidewalks and curb ramps Bus stop enhancements Crash reduction Bookend intersections From July 19 to July 25, 2024, the question asking respondents to select the five elements they are most excited about as the project moves into further design was mandatory in the questionnaire. In response to community input, on July 25, the question was made optional, and respondents were able to skip the question without selecting at least one design element. At least 73 respondents indicated choosing a design element because it was a mandatory field and not due to their excitement about it. Feedback gathered during the in-person and virtual open houses and online questionnaire is incorporated into the final CEAP. Input from this round of community engagement continued the themes and priorities heard in the first two open houses and added new input focused on the recommended north side two-way bike facility, potential for increased traffic congestion and related emissions caused by vehicle lane repurposing, and including anticipated future growth in vehicle use in traffic modeling. Further context for how input from this round of community engagement is addressed in the proposed project is below. North Side Two-Way Bike Facility Community engagement and education in future phases will focus on the most frequently asked questions and ensure users have access to information about using, connecting to, and crossing the two-way protected bike lane. The potential for conflicts with turning vehicles is minimized by locating the two-way protected bike lane on the north side of the Iris Avenue, which has fewer conflicts with driveways and side streets. Design features such as protected intersection elements, raised crossings, two-way signs and markings, striping and signal changes that separate vehicle and bike movements at intersections, accounting for speed of vehicles and bicycles, will be detailed in the final design phase to reduce potential conflicts between bicyclists and drivers at side streets and driveways. Potential for Increased Traffic Congestion and Emissions Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 61 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 73 of 111 Transportation research does not find that vehicle lane repurposing results in increased emissions. Instead, it finds traffic emissions reductions from congestion mitigation are not guaranteed and demand based emissions reduction strategies can be more effective,12 and find reduction in fine particulate emissions with multimodal improvements on a corridor.13 Although Alternative B may potentially increase travel time by a range of 2 to 58 seconds for most trips (95%), all alternatives would increase current travel times due to the introduction of traffic signal changes and FHWA proven safety countermeasures to separate vehicle and pedestrian/bike movements at intersections. Potential for Future Growth in Vehicle Use Traffic modeling for the Iris Avenue project utilized existing vehicle, bicycle and pedestrian volumes. This approach is supported by the Boulder Valley Comprehensive Plan transportation and land use assumptions, 2023 Travel Diary Study findings of reduced single occupancy vehicle use and increased bicycling over the past nine years, and ten years of historic data that show vehicle volumes have remained reasonably constant. Project Process The project considered 13 possible design options including a range of solutions that explored different bike and pedestrian facility types, multi-use paths, as well as a range of lane configurations, from two to five vehicle lanes. The options were screened and then evaluated using the CEAP and project-specific criteria. Neighborhood Side Streets In response to community input, a secondary study area was added to the project to examine the potential for neighborhood traffic calming. Emergency Evacuation Alternative B allows for the use of the center-two way turn lane for eastbound personal vehicle travel while the two-way protected bike lane is wide enough to accommodate westbound disaster emergency response vehicles. Roadway design features for the use of the center turn lane as a second eastbound evacuation lane will continue to be coordinated with ODM, BPD, and BFRD during final design. 12 https://www.sciencedirect.com/science/article/abs/pii/S1361920912000727 13 https://www.sciencedirect.com/science/article/abs/pii/S1361920914001254 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 62 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 74 of 111 Bookend Intersection Safety Modifications and multimodal improvements like geometry changes, improved sidewalks, and bike path connections will improve separation and protection of each mode to the bookend intersections while maintaining the vehicle lane configuration. Signalized crossings and markings will connect bicyclists to paths on and across the bookend intersections at Broadway and 28th Street. Transit, Waste, and Delivery Operations Stakeholder outreach with Regional Transportation District (RTD), businesses on the eastern end, waste services, delivery services, and other key stakeholders will continue to inform final design. Design and operations details will be finalized as the corridor design progresses to final design and may change based on engineering best practices and technical feasibility. Additionally, themes from this most recent phase of community engagement reiterated previously heard concerns and desires and did not reveal new or diverging themes. These continued themes influenced the finalization of the content of the CEAP and public facing materials. Staff will update the project website and future materials to include information about these most frequently asked questions and continue to provide clarification and understanding for the community as the project moves forward into final design. Feedback has influenced the project process from the start, adding a secondary study area in response to concerns about vehicle speeds and traffic diversion to neighborhood side streets and projects on those streets to the project scope. Recurring themes throughout the project confirm the varying perspectives in the community and staff’s recommendation of Alternative B as the alternative that best balances those perspectives. Due to the nature of transportation capital improvement projects, many details are yet to be finalized as the project progresses into final design. Community feedback provides the priorities on which to focus such as the south side sidewalks and access to the bike facility on the north side, an emphasis on high quality and aesthetically pleasing design, innovative designs which preserve as much tree canopy as possible, and other designs and signal practices that best balance the trade-offs in safety, comfort, and connectivity for people walking, biking, riding transit and driving. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 63 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 75 of 111 Recommended Alternative The recommended alternative is Alternative B: Two-Way Protected Bike Lane and No Change to Roadway Width (Figure 24). Alternative B advances the 2019 Transportation Master Plan and 2019 Low Stress Walk and Bike Network Plan recommendations for Iris Avenue, respond to the findings of the 2022 Safe Streets Report, and implements recommendations of the 2023 – 2027 Vision Zero Action Plan. Figure 24 Alternative B: Three vehicle lanes with north side on-street protected two-way bike lane with minimum improvements behind the curb (Looking West) Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 64 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 76 of 111 Alternative B repurposes a vehicle lane which is effective at reducing speeds, a community priority that is supported by data that show prevailing speeds are 5 mph over posted speed limit and high-end speeders (about 4% of all drivers) traveling at 10+mph over the posted speed limit. Repurposing a lane provides space for a center turn lane. A center turn lane is effective at reducing the common crash types on Iris Avenue, rear ends and approach turns, by removing turning vehicles from through lanes. Repurposing a lane also provides space at intersections for protected intersection elements. Protected intersections are an industry best practice to reduce conflicts at intersections where the city’s data show most crashes occur. Repurposing a lane provides space for potential pedestrian refuge islands and improved bus stops, which reduces crossing distance and the time people walking and biking are exposed to traffic while crossing Iris Avenue. Finally, repurposing a lane provides space to provide hardened separation, or protection, between the on-street bike lane and vehicle lanes. This hardened separation also increases separation between people walking on the sidewalks and vehicle lanes, which increases pedestrian comfort. Alternative B includes a two-way protected bike lane on the north side of the street and removes the on-street bike lane on the south side of the street. This shifts the vehicle travel lanes 15 feet further from the north side of the street and 5 feet closer to the south side of the roadway. The existing sidewalk on the south side of the street is attached to the roadway for 37% of its length, which reduces pedestrian comfort for this stretch. The remaining 63% of sidewalk on the south side will retain its current detachment and associated pedestrian comfort. Design and construction may offer opportunities to reduce the proportion of attached sidewalk on the south side of the road. The two-way protected bike lane on the north side of Iris Avenue provides more benefits than one-way bike lanes because it is easier to maintain, provides more space for snow storage in winter months, can better gain benefits of sun exposure in winter months to melt and evaporate snow and ice furthering snow and ice response efforts, provides opportunities for passing – which is becoming increasingly important as more electric micro mobility devices use the transportation network, provides space for side-by-side riding, crosses nearly a third as many conflicting unsignalized driveways and side streets as the south side of the roadway, and is wide enough to support disaster emergency response vehicles. Alternative B can be implemented within the existing curb-to-curb width which retains all but 10 to 12 existing public street trees, reduces the time and complexity to implement because of fewer utility relocations, stormwater drainage impacts, floodplain permit mitigations, and time and funding to implement. This lower cost project supports implementation of traffic calming and management on neighborhood streets under limited transportation funding scenarios. Alternative B has the lowest potential travel time increase of the three lane alternatives for both the average trips, 3 to 46 seconds, and 2 to 58 seconds for most trips (95th percentile). These potential travel time increases are 20 to 30 seconds more than the potential travel time increase of the four lane alternatives (Alternative C and D). Alternative B has a potential travel time increase for the slowest trips, which about 5% of drivers experience, by up to 20 seconds more than the other three lane alternative (Alternative A) and up to one minute more than both four lane alternatives (Alternative C and D). While the potential travel time changes may feel impactful to some, Alternative B provides the greatest safety benefits for all. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 65 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 77 of 111 Throughout the project, community input themes and priorities were: • Concern for emergency evacuation • Concern for traffic congestion leading to cut through traffic on neighborhood side streets • Desire for slower vehicle speeds • Desire for better walking and biking facilities along Iris Avenue as well as safer and more comfortable crossings • Desire for vehicle travel time reliability Alternative B provides the benefits the community has asked for. Note: Staff will identify specific locations along neighborhood street segments to receive speed mitigation and traffic management, prioritized by the largest speeding problem. These prioritized segments will receive speed mitigation and traffic management when the Iris Avenue project is implemented, following final design and allocation of funding. This may include speed humps, speed tables, and vehicle turn restrictions. The project team reviewed Alternative B with various work groups within the City of Boulder, including Urban Forestry, Transportation Maintenance, and Utilities/Floodways/Greenways for feedback and these partners did not identify any issues that would preclude their support. The project team has worked in close coordination with the Boulder Fire-Rescue and Police departments, and the Office of Disaster Management (ODM) for the City of Boulder and Boulder County, to review considerations around day-to-day and disaster emergency response. These key partners support the use of the center-turn lane for day-to-day emergency response and use of the two-way protected bike lane for disaster emergency response and advise that use of the center turn lane can provide two eastbound evacuation lanes during disaster scenarios. Staff will continue to work with these partners in the final design phase to develop design solutions that would support evacuation use of the center-turn lane during disaster scenarios. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 66 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 78 of 111 Staff Project Manager and Relevant Contacts PROJECT MANAGER Lindsay Merz, P.E., PMP, ENV SP Engineering Principal Project Manager City of Boulder Transportation & Mobility Department Email: MerzL@bouldercolorado.gov TRANSPORTATION PLANNER – ENGAGEMENT Ericka Amador Senior Transportation Planner City of Boulder Transportation & Mobility Department Email: amadore@bouldercolorado.gov TRANSPORTATION PLANNER – DESIGN Daniel Sheeter Principal Transportation Planner City of Boulder Transportation & Mobility Department Email: sheeterd@bouldercolorado.gov OPERATIONS ENGINEER Greg Baker Transportation Engineer HDR Email: Gregory.Baker@hdrinc.com PROJECT TEAM Melanie Sloan Principal Project Manager City of Boulder Transportation & Mobility Department Email: sloanm@bouldercolorado.gov Devin Joslin, PE, PTOE Civil Engineering Senior Manager Principal Traffic Engineer City of Boulder Transportation & Mobility Department Email: joslind@bouldercolorado.gov Stephen Rijo Transportation Planning Manager City of Boulder Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 67 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 79 of 111 Transportation & Mobility Department Email: rijos@bouldercolorado.gov Gerrit Slatter Civil Engineering Senior Manager City of Boulder Transportation & Mobility Department Email: slatterg@bouldercolorado.gov CONSULTANT T EAM Charlie Dyrsten, PE Project Manager HDR Email: charles.dyrsten@hdrinc.com Alexa Muraida Senior Communications Strategist HDR Email: alexa.muraida@hdrinc.com Attachments Attachment A: Conceptual Alternatives with Considerations Applied Attachment B: CEAP Checklist Attachment C: CEAP Checklist Questions Attachment D: Conceptual Alternatives with Project-Specific Evaluation Criteria Applied Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 68 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 80 of 111 Attachment A: Conceptual Alternatives with Considerations Applied Alternative A: One-Way Protected Bike Lanes and No Change to Roadway Width Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 69 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 81 of 111 Alternative B: Two-Way Protected Bike Lane and No Change to Roadway Width Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 70 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 82 of 111 Alternative C: One-Way Protected Bike Lanes and Widened Roadway Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 71 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 83 of 111 Alternative D: Two-Way Protected Bike Lane and Widened Roadway Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 72 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 84 of 111 Attachment B: CEAP Checklist Evaluation for the Four Conceptual Design Alternatives The CEAP checklist rates each alternative (+) Positive effect, (-) Negative effect, and (0) No effect. Only criteria that had alternative impacts are shown. Alternative A Alternative B Alternative C Alternative D A. Natural Areas or Features 1. Disturbance to species, communities, habitat, or ecosystems due to: a. Construction activities - - - - f. Habitat removal 0 0 - - h. Changes to groundwater or surface runoff 0 0 - - 2. Loss of mature trees or significant plants? 0 0 - - B. Riparian Areas/Floodplains 1. Encroachment upon the 100- year, conveyance ore high hazard flood zones 0 0 0 0 2. Disturbance to or fragmentation of a riparian corridor 0 0 - - D. Geology and Soils d. Changes in soil or fill material on the site? 0 0 - - E. Water Quality 1. Impacts to water quality from any of the following? a. Clearing, excavation, grading or other construction activities 0 0 - - b. Change in hardscape 0 0 - - c. Change in site ground features 0 0 - - d. Change in storm drainage 0 0 - - e. Change in vegetation 0 0 - - Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 73 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 85 of 111 Alternative A Alternative B Alternative C Alternative D F. Air Quality 1. Short or long term impacts to air quality (CO2 emissions, pollutants)? a. From mobile sources? + + + + K. Physiological Well-being 1. Exposure to Excessive Noise 0 0 - - L. Services 1. Additional Need for: d. Police Services + + 0 0 e. Fire Protection Services + + 0 0 h. Transportation improvements/traffic mitigation + + 0 0 M. Special Populations 1. Effects on: a. Persons with disabilities? + + + + b. Senior population? + + + + c. Children or youth? + + + + d. Restricted income persons? + + + + e. People of diverse backgrounds (including Latino and other immigrants)? + + + + f Neighborhoods + + + + g. Sensitive populations located near the project (e.g. schools, hospitals, nursing homes)? + + + + N. Economy 1. Utilization of existing infrastructure? + + - - Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 74 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 86 of 111 Attachment C: CEAP Checklist Questions City of Boulder Community and Environmental Assessment Process Checklist Questions Note: The following questions are a supplement to the CEAP checklist. Only those questions indicated on the checklist are to be answered in full. Natural Areas and Features 1.Describe the potential for disturbance to or loss of significant: species, plant communities, wildlife habitats, or ecosystems via any of the activities listed below. (Significant species include any species listed or proposed to be listed as rare, threatened or endangered on federal, state, county lists.) a.Construction activities Mature trees may provide habitat – but this has not been evaluated for the project. It is assumed that by removing trees the potential for providing habitat is also removed. All alternatives will disturb the wildlife habitats due to construction activity. Alternatives A and B will have a negative effect due to typical construction activities. These activities will be limited to within the roadway width plus space necessary outside of the roadway width for construction activities. Alternatives C & D will have a negative effect due to the widening of the roadway these require to build, which increases the footprint of disturbance during construction. b.Native Vegetation removal c.Human or domestic animal encroachment d.Chemicals to be stored or used on the site (including petroleum products, fertilizers, pesticides, herbicides) e.Behavioral displacement of wildlife species (due to noise from use activities) Alternatives A and B will have a positive effect because each propose three vehicle lanes, which will reduce road noise and therefore reduce the potential for behavioral displacement of wildlife species. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 75 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 87 of 111 Alternatives B and C maintain four vehicle lanes and so will have no effect on road noise and so will continue any current behavioral displacement of wildlife species due to road noise. f. Habitat removal Mature trees may provide habitat – but this has not been evaluated for the project. It is assumed that by removing trees the potential for providing habitat is also removed. Alternatives A and B will have no effect on habitat removal because tree removal is limited to improve sightlines. Alternatives C and D will have a negative effect on habitat removal because each require removal of 43 to 75 public street trees, or 29% to 50% of the existing tree canopy on Iris. Alternative C has the greatest negative effect because it requires the roadway to be widened to the north and south. This alternative would remove 69 – 75 public street trees, or 46-50% of all existing public street trees. Alternative D has a significant negative effect but requires the roadway to be widened to the north only. This alternative would remove 43 – 50 public street trees, or 29 – 32% of all trees. g. Introduction of non-native plant species in the site landscaping h. Changes to groundwater (including installation of sump pumps) or surface runoff (storm drainage, natural stream) on the site Alternatives A and B have no effect to groundwater because they are implemented within the existing roadway width. Alternatives C and D have a negative effect because they widen the roadway and increase hardscape and runoff. Alternatives C and D have a negative effect because they require the open Twomile Canyon creek to be piped, which cause a loss in vegetation and the environmental benefits of catching and filtering runoff before it enters groundwater. Alternatives A and B do not require the creek to be piped and so have no effect. i. Potential for discharge of sediment to any body of water either short term (construction-related) or long term j. Potential for wind erosion and transport of dust and sediment from the site Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 76 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 88 of 111 2.Describe the potential for disturbance to or loss of mature trees or significant plants. Alternatives A and B require removal of 7 mature trees to for improved sidewalks and sightlines. Alternative C requires the removal of 43 mature trees. Alternative D requires the removal of 32 mature trees. •A description of how the proposed project would avoid, minimize, or mitigate identified impacts. Impacts to existing street trees vary between the alternatives. Only trees located within the public right-of-way are impacted. Any trees located on private property will remain, with potential trimming only needed if low-hanging branches and/or limbs are impeding existing or new sidewalks and bike lanes. Alternatives A and B have no effect because they have minimal changes to existing public street trees: 10 – 12 need to be removed for sidewalk improvements and sightlines, or about 8% of the urban forest on Iris. Alternatives C and D have a negative effect because they require removal of a large number of trees. Alternative C has a greater negative effect than Alternative D because it removes 69 – 75 trees, or 46-50% of the urban forest on Iris Avenue. Alternative D has a less negative effect than Alternative C because it removes 43 – 50 trees, or 29-32% of the urban forest on Iris Avenue. •A habitat assessment of the site, including: 1. a list of plant and animal species and plant communities of special concern found on the site; 2. a wildlife habitat evaluation of the site. •Maps of the site showing the location of any Boulder Valley Natural Ecosystem, Boulder County Environmental Conservation Area, or critical wildlife habitat. Riparian Areas and Floodplains 1.Describe the extent to which the project will encroach upon the 100-year, conveyance or high hazard flood zones. Iris Avenue is currently designed to convey the 100-year flood, conveyance, and high hazard zones of Twomile Canyon Creek from Broadway to Elmers Twomile Creek. Therefore, all alternatives are within the 100-year flood, conveyance, and high hazard zones of Twomile Canyon Creek. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 77 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 89 of 111 A City of Boulder Floodplain Development Permit and a Clean Water Act (CWA) Section 404 Permit will be obtained prior to construction. The floodplain permit requires demonstration that the recommended alternative would cause no rise in the floodplain. No alternative causes a rise in the floodplain and no alternative removes any property from the floodplain. 2. Describe the extent to which the project will encroach upon, disturb, or fragment a riparian corridor: (This includes impacts to the existing channel of flow, streambanks, adjacent riparian zone extending 50 ft. out from each bank, and any existing drainage from the site to a creek or stream.) Alternatives A and B have no effect because they do not encroach on a riparian corridor. Alternatives C and D have a negative effect because they encroach into the riparian area of Twomile Canyon Creek on the northeast corner of Broadway and Iris Avenue. If potential impacts have been identified, please provide any of the following information that is relevant to the project: • A description of how the proposed project would avoid, minimize, or mitigate identified impacts to habitat, vegetation, aquatic life, or water quality. • A map showing the location of any streams, ditches and other water bodies on or near the project site (Figure 25). Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 78 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 90 of 111 Figure 25: Two mile Canyon Creek and Farmers Ditch on Iris Avenue • A map showing the location of the 100-year flood, conveyance, and high hazard flood zones relative to the project site (Figure 26). Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 79 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 91 of 111 Figure 26: Iris Avenue 100-Year Floodplain, High Hazard, and Conveyance Zone Wetlands 1. Describe any disturbance to or loss of a wetland on site that may result from the project. The project area includes wetlands of Elmers Twomile Canyon Creek. However, the roadway is elevated above the wetlands and so each alternative has no effect for disturbances. All alternatives would need to receive a wetlands permit to be built. If potential impacts have been identified, please provide any of the following information that is relevant to the project: • A description of how the proposed project would avoid, minimize, or mitigate identified impacts. • A map showing the location of any wetlands on or near the site. Identify both those wetlands and buffer areas which are jurisdictional under city code (on the wetlands map in our ordinance) and other wetlands pursuant to federal criteria (definitional) (Figure 27). Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 80 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 92 of 111 Figure 27: Iris Avenue Wetlands Geology and Soils 1. Describe any: a. impacts to unique geologic or physical features; b. geologic development constraints or effects to earth conditions or landslide, erosion, or subsidence; c. substantial changes in topography; or d. changes in soil or fill material on the site that may result from the project. Alternatives A and B have no effect because they can be implemented within the existing roadway width and so make no changes to fill materials. Alternatives C and D have a negative effect because each widen the roadway into vegetated areas. This widening will change the fill material. If potential impacts have been identified, please provide the following: Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 81 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 93 of 111 • A description of how the proposed project would avoid, minimize, or mitigate identified impacts. • A map showing the location of any unique geologic or physical features, or hazardous soil or geologic conditions on the site. Water Quality 1. Describe any impacts to water quality that may result from any of the following: a. Clearing, excavation, grading or other construction activities that will be involved with the project; Alternatives A and B have no effect on excavation, grading or other construction activities because they can be implemented within the current roadway width. Alternatives C and D will have a negative effect because they both require excavation and grading or other construction activities. Alternative C has a greater negative effect because it widens the roadway to the north and south. Alternative D has a negative effect but only widens the roadway to the north. b. Changes in the amount of hardscape (paving, cement, brick, or buildings) in the project area; Alternatives A and B have no effect to hardscape because they can be implemented within the current roadway width with spot improvements to the five-foot existing sidewalks. This means that hardscape will not be increased with either alternative and existing planting area will generally remain unchanged. Alternatives C and D widen the roadway and so increase hardscape and widen the existing five-foot sidewalk to six-foot sidewalk on one (Alternative D) or both (Alternative C) sides of the road. These changes will result in an increase in hardscape. Alternatives C and D will require water quality mitigation with permanent best management practices (BMPs), which result in these alternatives having no effect on water quality. c. Permanent changes in site ground features such as paved areas or changes in topography; Alternatives A and B have no effect on site ground features because they can be implemented within the current roadway width. Alternatives C and D will have a negative effect on site ground features because they both require clearing, excavation and grading during construction. Alternative C has a greater negative effect because it widens the roadway to the north and south. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 82 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 94 of 111 Alternative D has a negative effect because it widens the roadway to the north only. Both alternatives would have negative effects because they each widen the existing five- foot sidewalk to six-foot on one (Alternative D) or both (Alternative C) sides of the road. d.Changes in the storm drainage from the site after project completion; Alternatives A and B have no effect on storm drainage because they can be implemented within the current roadway width and so do not increase runoff. Alternatives C and D have a negative effect because they require the roadway to be widened and widen the existing five-foot sidewalk to six-foot both on one (Alternative D) or both (Alternative C) sides of the road. The increased hardscape of both alternatives increases runoff and the need for storm sewer inlets. e.Change in vegetation; Alternatives A and B will have no effect on vegetation removal because they can be built within the existing roadway width. Alternatives C and D will have a negative effect on vegetation: Alternative C has the greatest negative effect because it requires the roadway to be widened to the north and south and so has the greatest vegetation removal; Alternative D has negative effect but less than Alternative C because it widens the roadway to the north, only, and so does not disturb vegetation to the south. f.Change in pedestrian and vehicle traffic; g.Potential pollution sources during and after construction (may include temporary or permanent use or storage of petroleum products, fertilizers, pesticides, or herbicides). 2.Describe any pumping of groundwater that may be anticipated either during construction or as a result of the project. If excavation or pumping is planned, what is known about groundwater contamination in the surrounding area (1/4 mile in all directions from the project) and the direction of groundwater flow? All alternatives have no effect on groundwater pumping. During construction of the recommended alternative, surface water runoff will be treated by installing Best Management Practices (BMPs) according to the Colorado Storm Water Discharge Permit. If potential impacts have been identified, please provide any of the following that is relevant to the project: •A description of how the proposed project would avoid, minimize, or mitigate impacts to water quality. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 83 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 95 of 111 •Information from city water quality files and other sources (state oil inspector or the CDPHE) on sites with soil and groundwater impacts within 1/4-mile radius of project or site. •If impacts to site are possible, either from past activities at site or from adjacent sites, perform a Phase I Environmental Impact Assessment prior to further design of the project. •Groundwater levels from borings or temporary piezometers prior to proposed dewatering or installation of drainage structures. Air Quality 1.Describe potential short or long term impacts to air quality resulting from this project. Distinguish between impacts from mobile sources (VMT/trips) and stationary sources (APEN (report), HAPS (factories, refineries, boilers, power plants)). All alternatives have a positive effect on air quality because they provide safer walking and bicycling options along the corridor, which can reduce mobile source emissions. Alternatives A and B provide a greater positive effect because they also provide space for protected intersection elements, shorter crossing distances, and opportunity for refuge islands at midblock crossings, creating safer and more comfortable crossings of Iris Avenue as well. Alternatives C and D only provide protected bike lanes and sidewalk improvements but no safer and more comfortable crossings, and so have a smaller positive effect on Air Quality than Alternatives A and B. Emissions from construction equipment would have a short term effect on air quality during construction. The effects of the emissions would be negligible because of the small number of short term emission sources. The manufacture and use of construction materials can produce short-term impacts to air quality at the manufacture or construction site. The general types of construction and construction materials are similar for all alternatives. Resource Conservation 1.Describe potential changes in water use that may result from the project. a.Estimate the indoor, outdoor (irrigation) and total daily water use for the facility. b.Describe plans for minimizing water use on the site (Xeriscape landscaping, efficient irrigation system). Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 84 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 96 of 111 2. Describe potential increases or decreases in energy use that may result from the project. a. Describe plans for minimizing energy use on the project or how energy conservation measures will be incorporated into the building design. b. Describe plans for using renewable energy sources on the project or how renewable energy sources will be incorporated into the building design. c. Describe how the project will be built to LEED standards. 3. Describe the potential for excess waste generation resulting from the project. If potential impacts to waste generation have been identified, please describe plans for recycling and waste minimization (deconstruction, reuse, recycling, green points). Cultural/Historic Resources 1. Describe any impacts to: a. a prehistoric or historic archaeological site; b. a building or structure over fifty years of age; c. a historic feature of the site such as an irrigation ditch; or d. significant agricultural lands that may result from the project. If potential impacts have been identified, please provide the following: • A description of how the proposed project would avoid, minimize, or mitigate identified impacts. Visual Quality 1. Describe any effects on: a. scenic vistas or views open to the public; b. the aesthetics of a site open to public view; or c. view corridors from the site to unique geologic or physical features that may result from the project. Safety 1. Describe any additional health hazards, odors, or exposure of people to radon that may result from the project. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 85 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 97 of 111 2.Describe measures for the disposal of hazardous materials. 3.Describe any additional hazards that may result from the project. (Including risk of explosion or the release of hazardous substances such as oil, pesticides, chemicals or radiation) If potential impacts have been identified, please provide the following: •A description of how the proposed project would avoid, minimize, or mitigate identified impacts during or after site construction through management of hazardous materials or application of safety precautions. Physiological Well-being 1.Describe the potential for exposure of people to excessive noise, light or glare caused by any phase of the project (construction or operations). Alternatives A and B have no effect on exposure to excessive noise, light or glare from construction because they can be built within the existing roadway width and so are more easily and quickly implemented. Alternatives C and D have a negative effect on exposure to excessive noise, light or glare from construction because they require roadway widening and so are more complex and take more time to implement. The longer it takes to construct improvements, the greater impacts will be to adjacent property owners and the traveling community. Alternatives C and D have a negative effect on physiological well-being during construction, because they require significant tree removals, and after implementation by moving the existing curbs closer to adjacent properties and so increasing road noise for those homes. 2.Describe any increase in vibrations or odor that may result from the project. If potential impacts have been identified, please provide the following: •A description of how the proposed project would avoid, minimize, or mitigate identified impacts. Services 1.Describe any increased need for the following services as a result of the project: Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 86 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 98 of 111 a. Water or sanitary sewer services b. Storm sewer / Flood control features c. Maintenance of pipes, culverts and manholes d. Police services Alternatives A and B provide a positive effect on police services because they moderate speeds and crash potential by repurposing a vehicle lane and provide space at intersections for protected intersection elements. Alternatives A and B have a positive effect on day-to-day police services because they provide center turn lanes, which can be used for day-to-day police emergency response. Alternative B improves disaster emergency response because it provides a continuous two-way bike lane. The two-way bike lane is wide enough to function as a dedicated fire response lane during a disaster scenario. Roadway design features for the use of the center turn lane as a second eastbound evacuation lane will continue to be coordinated with ODM, BPD, and BFRD. Alternatives C and D are rated as having no effect because they provide limited positive effect on police services. Alternatives C and D maintain the current number of vehicle lanes and so do not moderate speeds, reduce crash potential or address the common crash types. Both alternatives provide protected bike lanes and sidewalk improvements but do not provide space at intersections for protected intersection elements. Therefore, they are less effective at decreasing the frequency and severity of crashes involving vulnerable road users. Alternatives C and D have no effect on day-to-day police emergency services because they do not provide center turn lanes. Therefore, police vehicles must use vehicle lanes which can be difficult to navigate around personal vehicles on the road. Alternative D includes a two-way protected bike lane, but it is not continuous due to right-of-way constraints near 16th Street. Because the two-way bike lane is discontinuous, fire response does not have a dedicated fire response lane for the length of the project. e. Fire protection Alternatives A and B have a positive effect on day-to-day fire protection services because they include center turn lanes which provide dedicated space for fire response vehicles. Alternative B improves disaster emergency response because it provides a continuous two-way bike lane. The two-way bike lane is wide enough to function as a dedicated fire response lane during a disaster scenario. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 87 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 99 of 111 Alternatives C and D have no effect on day-to-day fire protection services because they maintain the current vehicle lanes, which can be difficult for fire response vehicles to navigate around personal vehicles on the road. Alternative D includes a two-way protected bike lane, but it is not continuous due to right-of-way constraints near 16th Street. Because the two-way bike lane is discontinuous, fire response does not have a dedicated fire response lane for the length of the project. f. Recreation or parks facilities g. Libraries h. Transportation improvements/traffic mitigation Please refer to Project Specific Evaluation Results section for more detail on this checklist question. i. Parking j. Affordable housing k. Open space/urban open land l. Power or energy use m. Telecommunications n. Health care/social services o. Trash removal or recycling services 2. Describe any impacts to any of the above existing or planned city services or department master plans as a result of this project. (e.g. budget, available parking, planned use of the site, public access, automobile/pedestrian conflicts, views) Special Populations 1. Describe any effects the project may have on the following special populations: a. Persons with disabilities b. Senior population c. Children or Youth All alternatives have a positive effect for persons with disabilities, senior population, children and youth and sensitive populations, like school children attending Columbine and Foothill elementary schools and people living with disabilities like those living at Smart Home Imagine! because they each provide improved sidewalks, Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 88 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 100 of 111 protected bike lanes and Americans with Disabilities Act curb ramp compliance work. Alternatives A and B provide a greater positive effect than Alternatives C and D because they repurpose a vehicle lane. Repurposing a lane provides space for protected intersection elements at intersections and pedestrian refuge islands at midblock crossings, which reduce the exposure of vulnerable users to vehicles. Alternatives B and D provide a greater positive effect than Alternatives A and C because they provide a two-way protected bike lane. The two-way facility better serves all ages and abilities bicyclists because the additional width allows for passing and side-by-side riding. Therefore, Alternative B provides the greatest positive effect for special populations. d. Restricted income persons e. People of diverse backgrounds (including Latino and other immigrants) Columbine Elementary school has high percentages of low income, Hispanic and English Language Learner students. More than 60% of students attending Columbine receive free or reduced lunch, 58.5% identify as Hispanic and more than 40% of students are English Language Learners. The Boulder Housing Partners Iris-Hawthorn affordable housing community includes low income residents of diverse backgrounds. Nationally, low income households are more likely to walk, bike or use transit to reach their daily needs, and people of color are more at risk for crashes and severe injury crashes. All alternatives have a positive effect for low income individuals and people of color because they each provide improved sidewalks, protected bike lanes and Americans with Disabilities Act curb ramp compliance work. Alternatives A and B provide a greater positive effect than Alternatives C and D because they repurpose a vehicle lane. Repurposing a lane provides space for protected intersection elements at intersections and pedestrian refuge islands at midblock crossings, which reduce the exposure of vulnerable users to vehicles. Therefore, Alternatives A and B provide a greater positive effect than Alternatives C and D because A and B provide safer and more comfortable transportation options for low income individuals and people of diverse backgrounds. f. Sensitive Populations located near the project (e.g. adjacent neighborhoods or property owners, schools, hospitals, nursing homes) Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 89 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 101 of 111 All alternatives have no effect on neighborhoods because traffic calming and traffic management will be installed on specific parallel street segments when the Iris Avenue project is implemented. These installations will address speeding vehicles that divert to parallel streets today and potentially in the future as a result of changes to Iris Avenue. If potential impacts have been identified, please provide the following: • A description of how the proposed project would avoid, minimize, or mitigate identified impact. • A description of how the proposed project would benefit special populations. Economic Vitality 1. Describe how the project will enhance economic activity in the city or region or generate economic opportunities? 2. Describe any potential impacts to: a. businesses in the vicinity of the project (ROW, access or parking), All alternatives have no effect on current economic activity because none will make changes to vehicle lanes, and all will provide safer walking and biking connections to the main economic activity centers on the corridor: Willow Springs and Safeway shopping complexes at Iris Avenue and 28th Street. All alternatives propose to make access changes to reduce conflicts and make connections safer for everyone at the western most driveway to the Safeway shopping complex. Changes would remove westbound left turns into the westernmost driveway to the Safeway shopping complex on Iris Avenue due to the crash history at this location. Westbound drivers can continue to access the Safeway shopping complex from 28th Street. b. employment, c. retail sales or city revenue and how they might be mitigated. Alternatives A and B have a positive effect on utilizing existing infrastructure because they can be built within the existing roadway width. Alternatives C and D have a negative effect on utilizing existing infrastructure because they require roadway widening and so require additional infrastructure to be completed. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 90 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 102 of 111 Attachment D: Table of Mature Trees DBH in inches (Rounded) Preservation Code Mature Trees >6" Alt A Alt B Alt C Alt D 7 2 - Preserve if Possible 1 4 2 - Preserve if Possible 0 6 2 - Preserve if Possible 1 5 2 - Preserve if Possible 0 9 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 21 2 - Preserve if Possible 1 10 2 - Preserve if Possible 1 2 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 10 3 - Ok to Remove and Replace 1 5 3 - Ok to Remove and Replace 0 3 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 3 2 - Preserve if Possible 0 2 3 - Ok to Remove and Replace 0 13 3 - Ok to Remove and Replace 1 9 3 - Ok to Remove and Replace 1 5 3 - Ok to Remove and Replace 0 9 3 - Ok to Remove and Replace 1 2 3 - Ok to Remove and Replace 0 5 3 - Ok to Remove and Replace 0 7 3 - Ok to Remove and Replace 1 3 3 - Ok to Remove and Replace 0 4 3 - Ok to Remove and Replace 0 9 3 - Ok to Remove and Replace 1 3 3 - Ok to Remove and Replace 0 14 3 - Ok to Remove and Replace 1 41 1 - High Priority for Preservation 1 Impacted 25 2 -Preserve if Possible 1 Impacted 1 3 - Ok to Remove and Replace 0 Impacted 1 3 - Ok to Remove and Replace 0 Impacted 3 3 - Ok to Remove and Replace 0 Impacted 10 3 - Ok to Remove and Replace 1 8 3 - Ok to Remove and Replace 1 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 91 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 103 of 111 2 3 - Ok to Remove and Replace 0 Impacted 3 3 - Ok to Remove and Replace 0 Impacted 7 3 - Ok to Remove and Replace 1 Impacted 6 3 - Ok to Remove and Replace 1 Impacted 5 3 - Ok to Remove and Replace 0 Impacted 9 3 - Ok to Remove and Replace 1 9 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 9 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 9 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 7 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 8 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 11 1 - High Priority for Preservation 1 2 2 - Preserve if Possible 0 47 1 - High Priority for Preservation 1 7 2 - Preserve if Possible 1 5 2 - Preserve if Possible 0 3 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 10 1 - High Priority for Preservation 1 10 1 - High Priority for Preservation 1 9 1 - High Priority for Preservation 1 13 1 - High Priority for Preservation 1 2 3 - Ok to Remove and Replace 0 13 2 - Preserve if Possible 1 15 2 - Preserve if Possible 1 12 2 - Preserve if Possible 1 Impacted 11 2 - Preserve if Possible 1 6 2 - Preserve if Possible 1 16 2 - Preserve if Possible 1 3 3 - Ok to Remove and Replace 0 20 2 - Preserve if Possible 1 Impacted 10 2 - Preserve if Possible 1 Impacted 10 3 - Ok to Remove and Replace 1 Impacted 11 2 - Preserve if Possible 1 Impacted 14 2 - Preserve if Possible 1 Impacted 7 2 - Preserve if Possible 1 Impacted Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 92 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 104 of 111 14 2 - Preserve if Possible 1 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 20 1 - High Priority for Preservation 1 Impacted 19 1 - High Priority for Preservation 1 Impacted 2 2 - Preserve if Possible 0 1 2 - Preserve if Possible 0 Impacted Impacted 3 3 - Ok to Remove and Replace 0 Impacted Impacted 4 3 - Ok to Remove and Replace 0 Impacted Impacted 15 1 - High Priority for Preservation 1 Impacted Impacted 2 2 - Preserve if Possible 0 Impacted Impacted 16 1 - High Priority for Preservation 1 Impacted Impacted 11 1 - High Priority for Preservation 1 Impacted Impacted 33 1 - High Priority for Preservation 1 Impacted Impacted 17 1 - High Priority for Preservation 1 Impacted Impacted 13 1 - High Priority for Preservation 1 Impacted Impacted 2 3 - Ok to Remove and Replace 0 Impacted Impacted Impacted Impacted 7 2 - Preserve if Possible 1 Impacted Impacted Impacted Impacted 2 3 - Ok to Remove and Replace 0 Impacted Impacted Impacted Impacted 2 3 - Ok to Remove and Replace 0 Impacted Impacted Impacted Impacted 2 3 - Ok to Remove and Replace 0 Impacted Impacted Impacted Impacted 3 3 - Ok to Remove and Replace 0 Impacted Impacted Impacted Impacted 21 1- High Priority for Preservation 1 11 1- High Priority for Preservation 1 9 1- High Priority for Preservation 1 10 1- High Priority for Preservation 1 14 1- High Priority for Preservation 1 10 3 - Ok to Remove and Replace 1 Impacted Impacted 11 2 - Preserve if Possible 1 Impacted Impacted 11 2 - Preserve if Possible 1 12 2 - Preserve if Possible 1 Impacted Impacted 35 2 - Preserve if Possible 1 Impacted Impacted 4 Did not Evaluate 0 6 Did not Evaluate 1 5 Did not Evaluate 0 2 Did not Evaluate 0 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 93 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 105 of 111 5 Behind Private Fence - Did not Evaluate 0 32 2 - Preserve if Possible 1 Impacted Impacted 19 1- High Priority for Preservation 1 7 3 - Ok to Remove and Replace 1 36 1- High Priority for Preservation 1 11 County Owned - Did Not Evaluate 1 Impacted 8 County Owned - Did Not Evaluate 1 Impacted Impacted 12 County Owned - Did Not Evaluate 1 Impacted Impacted 10 County Owned - Did Not Evaluate 1 Impacted 9 County Owned - Did Not Evaluate 1 Impacted Impacted 10 County Owned - Did Not Evaluate 1 Impacted 11 County Owned - Did Not Evaluate 1 Impacted Impacted 8 County Owned - Did Not Evaluate 1 Impacted Impacted 18 County Owned - Did Not Evaluate 1 18 County Owned - Did Not Evaluate 1 11 County Owned - Did Not Evaluate 1 Impacted Impacted 19 County Owned - Did Not Evaluate 1 16 County Owned - Did Not Evaluate 1 Impacted Impacted 18 3 - Ok to Remove and Replace 1 Impacted Impacted 2 2 - Preserve if Possible 0 Impacted Impacted 33 3 - Ok to Remove and Replace 1 Impacted Impacted 3 3 - Ok to Remove and Replace 0 25 2 - Preserve if Possible 1 Impacted 19 2 - Preserve if Possible 1 Impacted 14 1 - High Priority for Preservation 1 Impacted 28 1 - High Priority for Preservation 1 Impacted 2 2 - Preserve if Possible 0 2 2 - Preserve if Possible 0 Impacted Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 2 2 - Preserve if Possible 0 Impacted 18 4 - Removed 1 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 94 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 106 of 111 Summary of Table of Mature Trees Option Alt A Summary Alt B Summary Alt C Summary Alt D Summary Total Impacted Trees 12 12 71 43 Total Mature Trees Impacted 7 7 43 32 Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 95 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 107 of 111 hdrinc.com August 27, 2024 Dear Lindsay Merz, PE, Re: Iris Avenue Transportation Improvements Project – Floodplain Impacts of Alternatives The purpose of this letter is to describe the overall impacts to the floodplain based on conceptual alternatives presented to the City and the public during corridor alternatives evaluation of the Iris Ave Project. This letter does not represent a final finding or include floodplain modeling. Those activities will occur during later design phases. ICON Engineering, Inc. is retained to provide detailed floodplain analysis of the preferred alternative and will continue to support the project in the final design phases to complete detailed floodplain analysis. The effective model for this area is from the 2015 Upper Goose Creek and Twomile Canyon Creek Flood Mapping Study Update and shows that Iris Avenue acts as a floodway moving stormwater west to east from Broadway to Elmer’s Two Mile Creek and Park. In general, any impact to the floodplain, or any construction project within the floodplain will trigger the need to study a design’s impact to the floodplain. All concepts considered for Iris Ave will trigger a similar study. Any rise in water surface elevation must be contained within the City’s Right-of-Way (ROW). Given the limited public ROW outside the floodplain today, this requirement means that any rise in the floodplain elevation will make the project difficult to permit. However, there are methods that can be used to negate rises in the floodplain, particularly over short distances and for small potential rises. Without substantial roadway reconstruction, continuous rises in the floodplain of any height would not be permitted within the project reach. Thirteen Iris Ave concepts were initially considered and screened with eight criteria. One of these criteria was “Likely impact to the floodplain”. If a concept impacted the floodplain with a likely rise, those concepts were removed from further analysis. Any alternative that reduced the existing roadway width would create a floodplain rise, and was therefore removed from additional consideration. Any alternative that widened the roadway or kept it the same width as existing was advanced for further review based on the floodplain criteria. Based on the full evaluation of the eight criteria, four alternatives were brought to further corridor study and analysis. These alternatives can be viewed on the next page. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP)Attachment E: Floodplain Memo 96 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 108 of 111 Alternative A Alternative B Alternative C Alternative D Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 97 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 109 of 111 For these four alternatives, ICON Engineering completed high level analysis of the impacts on the floodplain. HDR and ICON determined that there are implementable engineering solutions for any potential small rise that appeared in the analysis and that floodplain permitting would likely be achieved. Given that Iris Ave is a floodway, there are risks in this approach. Floodplain modeling will have to be completed in detail to determine final water surface elevations and all rises must either be removed through design changes or contained within City ROW. The following is a list of some risks and possible mitigation measures. Risk Mitigation Measure or Strategy Updated existing conditions modeling adds detail to the model that was lacking before and shows local rises in the pre-project conditions vs. the existing conditions. Work on public messaging that clarifies any existing conditions water surface rises due to additional detail in the hydraulic model. Bicycle lane raised protective elements such as curbs, low walls, and posts may result in a rise. Use lower profile elements down to a minimum of striping, use smoother elements with less roughness, spot lowering of sidewalk, spot lowering of the roadway crown, provide additional storm drain conveyance, purchase ROW to contain rise. New amenities such as trees, benches, and transit shelters may result in a rise. Move amenities outside the floodway, use lower profile elements such as transit shelters with no walls or half-height walls, spot lowering of sidewalk, spot lowering of the roadway crown, provide additional storm drain conveyance, purchase ROW to contain rise. While initial floodplain analysis is based on assumptions, existing analysis does not show dramatic floodplain changes and a selection of the above tools and creative engineering are anticipated to produce a no-rise situation for any of the four listed Alternatives. Sincerely, HDR Project Manager Charlie Dyrsten, PE ICON Project Manager Brian LeDoux, PE, CFM Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 98 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 110 of 111 Attachment F: Conceptual Alternatives with Project-Specific Evaluation Criteria Applied Each alternative was rated using the following scale: Scoring: -5 significantly poor/worse, -3 poor/worse -1 slightly poor/worse, 0 neutral, 1 slightly good/better, 3 good/better, 5 significantly good/better. Attachment A - Iris Ave Transportation Improvements Project Community & Environmental Assessment Process (CEAP) 99 09.09.24 TAB Agenda 6 - Iris Ave CEAP Page 111 of 111