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5 - Recommendation on the South Broadway Safety Project C I T Y O F B O U L D E R TRANSPORTATION ADVISORY BOARD AGENDA ITEM MEETING DATE: January 12, 2004 AGENDA TITLE: Public hearing and consideration of a recommendation on the South Broadway (SH-93) Safety Improvements Project PRESENTERS: Bill Cowern, Transportation Operations Engineer Mike Sweeney, Transportation Operations and Planning Coordinator EXECUTIVE SUMMARY: The purpose of this memorandum is to present materials to the TAB on the city’s efforts to determine an appropriate set of improvements on South Broadway at two intersections that have documented accident problems. The city of Boulder has received $300,000 of Federal - Hazard Elimination Program (HEP) funding from the Colorado Department of Transportation (CDOT) to address documented accident problems at the intersections of South Broadway and Darley Avenue, and South Broadway and Grinnell Avenue. A detailed summary of the accident Attachment A history is provided as . Specifically, accidents result from vehicles turning left from Darley Avenue or Grinnell Avenue and being hit by vehicles on South Broadway. City staff considered several alternatives, including combinations of traffic signals, medians to restrict movements and left-turn acceleration lanes. These treatments were combined and considered as a variety of alternatives. Based on key criteria such as cost and acceptance by CDOT, a list of five alternatives was generated. A comparison of the Attachment B five alternatives and their impact on the goals of this project are shown in . Additional treatments, such as permanent speed displays are being recommended to slow traffic on South Broadway. The speed displays were to be recommended with any alternative being considered. As the City conducted public meetings and the process unfolded, there were two alternatives which had some support from the surrounding community; would fall within the fiscal constraints of the Federal HEP funding budget; would be supported by city and CDOT staff; and would address the safety concerns. These alternatives are: AGENDA ITEM # 5 PAGE 1 1)Construct a traffic signal at the intersection of South Broadway and Grinnell Avenue, and construct a median treatment to restrict left turns from Darley Avenue. 2)Construct a traffic signal at the intersection of South Broadway and Darley Avenue, and construct a median treatment to restrict left turns from Grinnell Avenue. Attachment C A comparison of these two alternatives is shown in . From information gathered through our public process and the analyses to date, city staff has sought to formulate a recommendation which considers the varied interests of the community and provides a balanced and effective solution to these safety issues. Staff is recommending the construction of a new traffic signal at the South Broadway and Grinnell Avenue intersection and the construction of a median restricting left turns from Darley Avenue onto South Broadway. Fiscal Impacts: The HEP funding does not require any match from the city of Boulder, so it is anticipated that any improvements resulting from this process will be designed and constructed using only these federal funds. It is anticipated that the improvements outlined in the staff recommendation can be designed and constructed within the HEP funding budget, with a relatively small amount of city funding (<$5,000) spent for CDOT administrative charges. A new traffic signal would result in additional traffic signal maintenance cost for the city of Boulder. While the city does receive some funding from CDOT toward this effort, the long-term costs do exceed this funding. Some staff time has been required to conduct the public process and analyses to date, and additional staff time will be needed to take the project through the CDOT review and approval process. It is anticipated that the additional work will fall within the parameters of staff’s normal work plan. To date, approximately $12,000 has been spent on consulting services relating to this project. Other Impacts: There are several potential impacts associated with making improvements to these two intersections. 1)Additional traffic signals in the South Broadway corridor will degrade the signal progression in the corridor. 2)Traffic signals and medians which restrict turning movements will result in traffic diversion on surrounding residential streets. This traffic diversion could result in speed or volume issues which impact the quality of life in the neighborhood. 3)There is a fire station near the intersection of South Broadway and Darley Avenue. Improvements at this location directly impact the emergency response capability of this station. AGENDA ITEM # 5 PAGE 2 4)Concern has been expressed by homeowners near potential traffic signal locations that a traffic signal would degrade their quality of life and negatively impact their property values. Other Board and Commission feedback: There has been no Board or Commission review of this material to date. Public feedback: As part of the public process, city staff held three public meetings in the vicinity of the project area. Staff from the Transportation Division, the Fire Department, the Police Department, the Boulder Valley School District and the Colorado Department of Transportation was involved in the public process. Staff sought to maximize the possibility for public input by sending a direct mailing to 1,194 citizens living near these two intersections and notifying them of the upcoming meetings. Direct contact was made to New Vista High School, Fairview High School, Bear Creek Elementary School, Creekside Elementary School and Southern Hills Middle School to give information regarding the project and request they provide meeting information in their respective newsletters. Additionally, a Web site about the project, with pertinent background information was created at the start of the process and continues to be updated. The purpose of the first public meeting was to talk about the safety problem with the community, describe federal funding available and provide an initial opportunity for citizen input. During the first meeting, several options to address the safety concerns were generated by staff and the meeting participants. At the second public meeting, staff responded to questions asked at the first meeting and presented a summary of the pros and cons of each option previously identified. Because there were a larger number of treatments and locations to consider, staff generated an informal polling document which the public used to provide input on which alternative(s) Attachment D they supported. A copy of this polling document is provided as . The results of this informal polling effort were then summarized and used by city staff to further refine the viable options for this project. A summation of the informal polling Attachment E effort is provided as . This includes the results of the poll and information from emails by interested citizens. Through the public input, staff was able to discern that there was very little support for an alternative which limited access at both intersections. Many comments suggested support for a traffic signal at one of the two locations, and there was a marginal preference shown for the alternative with a traffic signal at South Broadway and Grinnell Avenue. At the third public meeting staff reviewed the public involvement of this project (for members of the community that had not been present at prior meetings) and then discussed how staff developed five alternatives, shortened this list to two likely alternatives and then decided upon one to be a staff recommendation. Staff spent much of the time discussing how this staff recommendation was developed. At the meeting, AGENDA ITEM # 5 PAGE 3 not all members of the public agreed with staff’s recommendation. However, most participants appeared to understand the reason for staff’s recommendation and agreed with staff’s recommendation. th On Monday, December 8, staff received a petition from residents living along Grinnell Avenue and adjacent streets. This position expressed the lack of support by those signing the petition, for the staff recommendation and instead offered support for an alternative utilizing a median to restrict movements at both intersections. A copy of the petition has Attachment F been included as . Staff Recommendation: Staff is recommending the installation of a new traffic signal at the South Broadway and Grinnell Avenue intersection and a median restricting left turns out of Darley Avenue onto South Broadway. The median would allow emergency response vehicles to still make this critical movement. Flashing red beacons with signs saying “Emergency Signal – Stop when Flashing Red” would be gate-posted for both directions on South Broadway. These devices would flash when the Fire Department departs from their station, toward South Broadway. In addition, staff is recommending the placement of one permanent speed display device in each direction on South Broadway to attempt to slow traffic in this corridor. Staff felt that this alternative did the best job of resolving the safety issues at these two intersections while minimizing the potential impact to the signal operations on S. Broadway; minimizing the potential impacts of diverted traffic into the surrounding neighborhood; and allowing the opportunity to do further enhancements in the neighborhood to address possible diversion impacts. The alternative does offer an improvement to the Fire Department’s emergency response from the Darley Fire Station. We recognize that this alternative will have impacts, such as traffic increases on Grinnell Avenue and on sections of Toedtli Avenue, but staff felt this alternative did the best job of balancing all the different goals and minimizing the impacts as a whole. Staff recommends monitoring of the traffic impacts of these improvements in the surrounding neighborhood and plans to conduct an “after” study several months after the completion of the improvements. Staff would forward the results of this study along with any additional staff recommendations for mitigation or additional improvements to the TAB for consideration. Analysis: Additional information concerning the existing traffic volumes, turning movement counts Attachment G and travel speeds on roadways within the study area is provided as . Additional information concerning the possible diversion of traffic on surrounding neighborhood streets, by either of the two traffic signal alternatives is provided as Attachment H . TAB member Krista Holland forwarded a list of questions to staff, concerning these improvements. Her questions and the responses from staff are summarized and included Attachment I as. AGENDA ITEM # 5 PAGE 4 Attachments: Attachment A – Summary of Accident Information Attachment B – Alternatives Goal Matrix Attachment C – Advantage Comparison for top Two alternatives Attachment D – Copy of public input request form Attachment E – Summary of Public Process Input Attachment F – Citizen Petition Attachment G – Existing Traffic Data Diagram Attachment H – Potential Traffic Diversion Diagram Attachment I – Questions from Krista Holland / Answers from staff AGENDA ITEM # 5 PAGE 5 ATTACHMENT I: Questions from TAB Member Krista Holland to City Staff . South Broadway Safety Improvements TAB Public Hearing on January 12, 2004 BOLD The answers are in . - Why or how would signal progression on Broadway be impaired by adding more signal? Signal progression represents how effective we are at minimizing the number of stops and the amount of time stopped that people experience as they move through a series of traffic signals. The more signals that you have in series along with the need to progress traffic in BOTH directions of travel makes providing good progression more difficult. Our ability to make a new signal work depends upon the location of the signal, the speed of traffic and how much green time we will have to give the side street. Location of a traffic signal at the Broadway and Grinnell intersection works better (degrades progression less) than a traffic signal at the Broadway & Darley intersection. Our Signal Operations Engineer, Joe Paulson will be present at the TAB meeting on th January 12 and he can answer further signal operations questions. - How does the fire department feel about the staff recommendation? The Fire Department would prefer to have a traffic signal at the Broadway & Darley intersection. However, they realize the significant impacts that such a signal would cause and were motivated by the evidence that the signal at Broadway & Grinnell would make more sense overall. They support the staff recommendation to have the median treatment at Darley and the signal at Grinnell. They also recognize that the median treatment at Darley, with the “gate-posted” flashing displays, represents an improvement over the situation they have currently at the Broadway & Darley intersection. - What is a "gate-posted" sign? Gate Posted, are signs/beacons placed to either side of an approaching vehicle. In this case a northbound or southbound vehicle on Broadway would see beacons both to the right (near the sidewalk) and to the left (in the median) of their vehicle. This gate posting effect enhances visibility and awareness of a sign or beacon display. - How effective have this type of emergency vehicle only median crossings been elsewhere? We are not aware of another location which is exactly like what is being proposed at the Darley intersection. Breaks in the median for fire department access are common, but they are not typically at intersections where other vehicles could use them. Likewise, median access control at roadways or driveways is common but does not usually have a break in the median allowing a use (like a Fire Truck) to turn out. Our staff and the staff from CDOT do feel that the design will be effective. While it is still physically possible to turn left through the median, a vehicle would have to place themselves on the wrong side of a median on Darley to do so. They would have to ignore several signs and drive across striping prohibiting their using this area. While there will be some violations, we think these will mostly be during off-peak times and that the device will be successful in correcting the accident problem that exists today. - Approximately how much more would a traffic signal cost than the proposed emergency vehicle median crossing at Darley? We have budgeted the cost of a new traffic signal on South Broadway to be approximately $200,000. This includes purchasing and constructing the poles and mast-arms, as well as the concrete work to provide the needed pedestrian connections on both sides. We would expect the cost of a traffic signal at either Grinnell or Darley to cost approximately this amount. The median treatment at Darley would cost approximately $ 50,000 with an additional $ 20,000 to provide the four flashing beacon displays ($70,000 total). The median at Grinnell would cost approximately $ 43,000 total. - Have you received any feed back from the business at Darley? If so what did they think of the staff recommendation? In addition to the Fire Department, there are medical office buildings on Darley, west of Broadway. The property owners and tenants for these buildings were included in the mailings for the public process. We have not received any feedback from the businesses and if representatives from the businesses have attended our meetings, then they did not identify themselves as such. th Teresa Spears will be present at the TAB meeting on January 12 and can answer any additional questions about the public process and the input received to date. - How much more traffic is expected on Grinnell due to the proposed traffic light? We anticipate the following peak hour traffic increases on Grinnell if a traffic signal is installed at the Broadway / Grinnell intersection: During the AM Peak hour: +35 west of Toedtli, +50 east of Toedtli Mid-Afternoon Peak hour: +20 west of Toedtli, +25 east of Toedtli The AM and Mid-Afternoon time periods are the hours when the most traffic turns left onto northbound Broadway. They correspond to the neighborhood and school drop-off outbound movement in the AM, and the High School / Middle School outbound movement in the afternoon. This may translate to a daily increase in traffic on this roadway of between 200 and 350 vehicles per day, west of Toedtli with a somewhat greater increase in the block between Toedtli and S.Broadway. The current traffic volume, west of Toedtli is approximately 2,400 vehicles per day.