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05.09.22 TAB Agenda 6 - DCS Transportation StandardsCITY OF BOULDER TRANSPORTATION ADVISORY BOARD AGENDA ITEM MEETING DATE: May 9, 2022 AGENDA TITLE: Transportation Standards Update (Phase 2) Briefing and TAB Feedback PRESENTER(S): Natalie Stiffler, Interim Director of Transportation and Mobility Gerrit Slatter, Principal Transportation Projects Engineer Scott Schlecht, Transportation Maintenance Manager Edward Stafford, Senior Manager –Planning and Development Services Department Michael Koslow, Civil Engineering Senior Project Manager David Thompson, Civil Engineering Senior Project Manager EXECUTIVE SUMMARY: This memo provides a status update on Phase 2 of the transportation portion of the City of Boulder Design and Construction Standards (DCS) Update. Phase 1 updates, which took place in 2019/2020, provided specific updates to Chapter 2, with a focus on clarification of standard, buffered and separated bike lane standards such that the DCS would be consistent with the Low-Stress Walk and Bike Network Plan. Phase 1 also updated the pedestrian ramp standards in Chapter 11. The Phase 1 update was adopted in February 2020. The Phase 2 DCS update will focus on Street Geometric Design and Streetscape/Landscaping Design and Maintenance and will also include an update to the Sight Triangle portion of the Boulder Revised Code 9-9-7 (BRC) (The BRC are regulations adopted though the legislative process by the City Council.) The purpose of the Phase 2 update is to align these sections with recently adopted policy and technical documents (e.g., Transportation Master Plan, Low-Stress Walk and Bike Network Plan, and internal Transportation Landscapes Plan) and to ensure that industry best practices are being followed. The DCS is used to help guide public infrastructure built by both private development and city funded capital infrastructure and maintenance projects. The Phase 2 project was initiated in June 2021, with an initial round of community engagement in September 2021. The team has developed initial “60%-level” recommendations for changes and is collecting input on these from the community and from boards in April-May 2022 with anticipated adoption of final updates to the documents in Q3 2022. 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 1 of 8 BACKGROUND: The current DCS was adopted in 1998 and had major updates in 2000 and again in 2020. The DCS exists to prescribe minimum standards to be used in the design and construction of infrastructure located in public right-of-way/easements of the city of Boulder, as well as private transportation improvements that connect to or impact public infrastructure. The DCS is enacted through the BRC, and changes are adopted by City Council with recommendations from appropriate boards, such as TAB and Planning Board. A number of DCS transportation standards have been previously identified for potential update, which has been based in part upon community feedback received over the years. Additionally, the Transportation Master Plan Update in September 2019, the Low-Stress Walk and Bike Network Plan in 2019 and completion of the Transportation Landscapes Plan in 2020, along with other transportation staff work, has highlighted additional items to be updated in the DCS and BRC. The proposed changes are intended to update relevant standards to current best practices and provide consistency between adopted master plans and the standards of the DCS. Additional updates to other sections of the DCS are anticipated in future years. The goals of the Phase 2 update are to: - Overall: Modernize the requirements to which facilities are designed and constructed so private and public projects are consistent and uniform in application. This aligns with the departments’ Operational Excellence guidepost and being more efficient in the delivery of our desired results. - Street geometric design: decrease the potential for and/or severity of conflicts between all users (motorists, bicyclists and pedestrians) by modifying conflict points, reducing the speed of vehicles at conflict points such as driveways and intersections, and increase visibility between modes. - Streetscape, landscaping, and irrigation: support landscapes that are fiscally maintainable with city resources and in line with the environmental sustainability goals highlighted in the Urban Forestry Strategic Plan and the Transportation Landscape Maintenance Plan. - Sight triangle section in the Boulder Revised Code: further embrace Boulder’s multimodal system by adding standards related to private land that relate to multi-use paths, increase visibility between modes at intersections and recognize the built environment’s impact to sight distance through the placement of buildings. COMMUNITY ENGAGEMENT: Community engagement has included targeted outreach to groups that regularly use the DCS and/or that have expressed an interest in the update (e.g., the development and engineering community, Community Cycles Advocacy Committee (CCAC) and TAB), as well as informing and consulting with the community at large. The team presented to CCAC and to the Center for People with Disabilities and also held three separate virtual office hours. Highlights of the initial (60%) recommendations, as well as working drafts of Chapters 2, 3, and 10 are posted on the project website for input through May 1. Some of the key themes of input received to date include: - Support for the proposed changes related to: o Narrower lane widths to slow vehicle traffic 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 2 of 8 o Minimizing the number of left turn lanes to minimize crossing distances - Support for additional raised crossing details (note: this is currently in progress and will be part of the 90% level recommendations) - Support for minimizing corner radii as a method to reduce turning vehicle speeds, as well as a desire to accommodate larger vehicles, such as transit - Reminder to build facilities that we can maintain - Concern about excessive signage and markings - Concern about pedestrians and people with disabilities being able to safely and easily navigate traffic circles In addition to this update (May 2022), TAB received a briefing in September 2021. The August 2022 TAB meeting will include a public hearing and TAB will be asked to make a recommendation to Planning Board and City Council regarding the proposed updates. Planning Board will receive a briefing in May 2022 and will have a public hearing and be asked for a recommendation to City Council in August 2022. The project is scheduled to be presented to City Council for approval in September 2022. PROJECT SCOPE: The scope of the Phase 2 update is focused on street geometric design and streetscape design and standards, as detailed below. Street Geometric Design The intent of the update to the Street Geometric Design (Section 2.07) is to consider changes to the standards of radius of intersections, curb returns, horizontal curves, lane widths, design speed and turning radii for improved bicyclist and pedestrian safety. The Street Geometric Design section is applicable to city-funded capital projects such as the North Broadway Reconstruction project currently under construction and the 30th Street Separated Bike Lanes project which will soon start design. It is also used on private development projects when a developer is responsible for implementing infrastructure in the public right-of-way. An example of this type of project is the Junction Place roadway between Pearl Parkway and Prairie. Within Section 2.07 STREET GEOMETRIC DESIGN, the following subsections and tables/figures were updated: Section 2.07 STREET GEOMETRIC DESIGN Topics: (A) Minimum Requirements (B) Right-of-Way (C) Lane Width—UPDATED (D) Horizontal Alignment—UPDATED (E) Vertical Alignment (F) Sight Distance—UPDATED (G) Medians (H) Vertical Clearance of Structures Tables: Table 2-5: Minimum Street Lane Widths— UPDATED Table 2-6: Minimum Horizontal Street Curve Specifications Table 2-6a: Separated Bike Lane Minimum Horizontal Curve Specifications—NEW Table 2-7: Minimum Street Spacing Table 2-8: Minimum Intersection Radii Table 2-8a: Relationship between Effective and Actual Radius for the Default Design Vehicle 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 3 of 8 (SU-30)—NEW Table 2-9: Maximum Street Grades Table 2-10: Vertical Curve Design Control Table 2-11: Median Width Design Standards Figures: Figure 1. Actual and Effective Radius at a Conventional Intersection Corner—NEW Figure 2. Actual and Effective Radius at a Conventional Intersection Corner with a Curb Extension—NEW Figure 3. Example of a Mountable Truck Apron at an Intersection Corner—NEW Highlights of the specific changes include: Vehicle Lane Widths Update lane widths table with new, narrower preferred widths for vehicle lanes to align with current best practice for constructing streets that serve people walking and bicycling. Anticipated benefit: Narrower vehicle lane widths typically yield slower vehicle speeds. Bicycle Lane Widths Add lane widths for all expected types of bike lanes including conventional, buffered, separated, and parking-protected. Anticipated benefit: Providing standard widths for bicycle lanes will lead to more consistent projects that prioritize bicyclist safety and comfort. Separated Bike Lanes Provide additional technical information about operating speed of bicyclists and the effect on design features. Anticipated benefit: Providing more nuanced information about separated bike lane design will lead to more consistent design of separated bike lanes that are comfortable for bicyclists of all ages and abilities. Road Width Tapers (Bike Lanes) Add information about bike lane tapers in addition to existing motor vehicle lane tapers. Anticipated benefit: Eliminating bike lane designs with abrupt tapers (changes in direction) that can cause rider discomfort Left-Turn Lanes Clarify goal to use a single left-turn lane first, then dual left turns if necessary. Add statement that triple left-turn lanes are only allowed with Director approval. Anticipated benefit: Reducing the number of left-turn lanes at intersections shortens crossing distances for pedestrians and bicyclists. While the focus of the update within Chapter 2 is Street Geometric Design (Section 2.07), for consistency and completeness, other related and incidental updates are also being proposed. For 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 4 of 8 example, the project team wanted to ensure that the new bike lane widths in Table 2-5 and other related details were now also reflected in Section 2.11 – Bicycle Facilities and Multi-Use Path Design. In addition, as new drawings were developed to address other design features (such as traffic circles and raised pedestrian crossings), staff put the additional related text in a new section for now (Section 2.14 – Traffic Calming); the team is still determining the best way to integrate this information in the final document. Highlights of the specific changes within Section 2.11 include: Separated Bike Lanes at Driveways Add new figures Figure 4 - Typical Layout for One-way Street Level Separated Bike Lanes at Driveways—NEW Figure 5 - Typical Layout for Sidewalk Level One-way Separated Bike Lanes at Driveways—NEW Anticipated benefit: Separated bike lanes typically cross driveways and alleys. Standardizing this element of design can improve visibility of bicyclists and improve yielding compliance. Separated Bike Lanes at Intersections Add new figures Figure 6 - Typical Layout of Street Level Separated Bike Lanes at Intersection in Retrofit Conditions—NEW Figure 7 - Typical Layout of Street Level Separated Bike Lanes at Intersections in Reconstructed Condition—NEW Figure 8 - Typical Layout of One-way Separated Bike Lane and Right Turn Lane—NEW Figure 9 - Typical Layout of One-way Separated Bike Lane and Right Turn Lane—NEW Anticipated benefit: The most complex aspect of separated bike lanes is at intersections. Providing examples of how to maintain safety and good sightlines through the intersection will lead to consistent design of future projects. Highlights of the new Section 2.14 include: Neighborhood Traffic Circles Add new figures Figure 10 – Typical Layout and Standard Dimensions of Neighborhood Traffic Circle—NEW Anticipated benefit: Neighborhood traffic circles are a great traffic calming technique for local streets. Standardizing their design with typical dimensions will help provide consistent design of future projects. Raised Crossings Add new figure Figure 11 - Typical Layout of Raised Crossing at Mid-Block Location— NEW 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 5 of 8 Anticipated benefit: Standardizing raised crossing design will help provide consistent traffic calming and yielding compliance benefits. Streetscape Design and Standards Chapters The intent of the update to the Streetscape Design and Standards chapters is to consider changes to tree buffer, irrigation and list of recommended plantings to use to reflect the Transportation Landscapes Plan and other Parks and Recreation and P&DS work efforts. The Streetscape Design and Standards chapters are used for both city capital project and private development public transportation infrastructure projects where there are landscape implementation elements. For example, the Diagonal Reconstruction project constructed in 2016 used Chapter 3 of the DCS as a standard. Within Chapter 3 and Chapter 10, the following sections and tables/figures were updated: Chapter 3 STREETSCAPE DESIGN AND TREE LOCATIONS Topics: 3.01 General—UPDATED 3.02 Landscaping Plan—UPDATED 3.03 Street Trees and Plants—UPDATED 3.04 Tree Removal and Relocation— UPDATED 3.05 Tree Protection for Construction Sites— UPDATED 3.06 General Landscaping and Maintenance Requirements—UPDATED Tables: Table 3-1: Approved Street Tree List for Non- paved Medians and Landscape Planting Strips—REMOVED Table 3-2: Limitations on Individual Tree Species—UPDATED Table 3-3: Tree Grates and Planting Pits Standards—UPDATED Table 3-4: Approved Street Tree List for Paved Areas Using Tree Grates and Planting Pits— REMOVED Table 3-5: Approved Median Shrub List— REMOVED Table 3-6: Tree Characteristics—REMOVED Chapter 10 STREETSCAPE & LANDSCAPE STANDARDS—RENAMED Topics: 10.1 General—UPDATED 10.2 Site Preparation—UPDATED 10.3 Planting—UPDATED 10.4 Seeding/Sodding—UPDATED 10.5 Permanent Underground Irrigation System—RENAMED AND UPDATED Tables: Table 10-1: Topsoil Mechanical Analysis Table 10-2: Minimum Root Ball Sizes— UPDATED Table 10-3: Wildflowers—REMOVED Table 10-4: Grasses—REMOVED Table 10-5: Soil Amendment Mix Mechanical Analysis Technical Drawings (Chapter 11) Chapter 11 contains technical drawings related to the above sections. The following new drawings were added: - Related to Section 2.07: o 2.07.L Bike Ramp and Pre-Cast Curb Buffer o 2.07.M Curb Extension Detail o 2.07.N Curb Extension Cross Sections 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 6 of 8 o 2.07.O Floating Bus Stop Detail – Intersection Far Side o 2.07.P Floating Bus Stop Cross Sections – Intersection Far Side - Related to Section 2.14: o 2.14.A Midblock Raised Pedestrian Crossing (from Ch. 2 Fig 11) - Related to Chapter 3: o Streetscape Tree Spacing and Location – Offset Drawing The following existing drawings were updated: - Related to Section 2.07: o 2.02.D Multi-Use Path Section Detail o 2.03 Crosspan and Radii Curb Return Accesses o 2.42.A Median Paved Curb Skirt o 2.42.C Median Separated Bike Lane o 2.51 Bicycle Path Cross-Section o 2.61.A Non-Residential Street Cross-Section Examples o 2.61.B Non-Residential Street Cross-Section Examples - Related to Chapter 3: o 3.01 Streetscape Tree Spacing and Location Drawing o 3.03 Tree Grate for Sidewalk Planting Drawing Boulder Revised Code 9-9-7 Sight Triangles The intent of the update to the Boulder Revised Code (BRC) is to consider changes to sightlines for improved safety for all travel modes. The specific section to be revised is 9-9-7. Highlights of the BRC 9-9-7 Sight Triangles updates include: 15’x15’ Sight Triangle Update the location of where the sides of the sight triangle are measured when the public street has a sidewalk in the existing figure. Currently the sight triangle is measured along the right-of-way line of the public street and either the right- of-way line of the public alley or the edge of the private driveway and whose third side is a line connecting the two sides. Anticipated benefit: This change will provide staff with physical features to measure the sides of the sight triangle when responding to sight triangle complaints. Multi-use path intersecting either an Alley or Driveway Add a new figure with a 15’ x 96’ sight triangle. The sides of the new multi-use path sight triangle would be 15’ x 96’ with the third side of the sight triangle being the line that connects the two sides. Anticipated benefit: The 15’ x 15’ sight triangle is currently used where a multi-use path (path) intersects with either a driveway or alley. The new sight triangle increases the sight triangle area between the path and either a driveway or alley. For additional details and links to figures and drawings, as well as full working draft documents, please visit the project website. 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 7 of 8 Timeline The project is expected to extend through Q3 2022, returning to TAB and Planning Board for recommendation to City Council in August and a City Council hearing for approval in September. NEXT STEPS: Next steps include continuing to gather input from the community and refining the initial recommendations into draft final (90%) recommendations. At the August 2022 TAB meeting the draft final (90%) recommendations will be presented; this meeting will be a public hearing, and TAB will be invited to make a recommendation to Planning Board and City Council. QUESTIONS FOR TAB: 1. What questions do you have about the community engagement? 2. What suggestions do you have to enhance the proposed changes? 05.09.22 TAB Agenda 6 - DCS Transportation Standards Page 8 of 8