Agenda Date: 11/06/2018
Subject:
Title
A resolution authorizing an Intergovernmental Agreement between the City of Littleton and the Colorado Department of Transportation (CDOT) for the installation of a dynamic lane assignment system at the intersection of South Platte Canyon Road (SH75B) and West Bowles Avenue
Body
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Presented By: |
Keith Reester, Public Works Director |
REQUESTED COUNCIL ACTION:
Does city council support entering into an Intergovernmental Agreement (IGA) with the Colorado Department of Transportation (CDOT) for reimbursement of costs associated with the installation of a dynamic lane assignment system at the intersection of South Platte Canyon Road (SH75B) and West Bowles Avenue that changes the northbound through lane at the intersection to a northbound shared through/right-turn lane?
BACKGROUND:
The intersection of South Platte Canyon Road at West Bowles Avenue currently experiences very high northbound right turning volumes, particularly during the weekday a.m. peak hour (690 vehicles). The intersection also has an elevated crash risk compared to similar intersections and has a demonstrated rear end crash problem, with the majority of those types of crashes involving the northbound right turn movement.
South Platte Canyon Road from West Bowles Avenue to West Mineral Avenue is the subject of a multi-jurisdictional coalition consisting of CDOT, the Town of Columbine Valley, Arapahoe County, and the City of Littleton. These agencies recently partnered on a corridor study) to identify existing and future deficiencies. The intersection of South Platte Canyon Road and West Bowles Avenue was identified as the highest priority location for improvement. A number of intersection capacity and signal operation strategies were evaluated. Ultimately, the coalition identified the addition of a second northbound right-turn lane at the intersection as the preferred alternative. Funding for this improvement is being pursued but is not likely for several years. In the meantime, a dynamic lane assignment system for the northbound approach would have operational and potential safety benefits by offering the ability to change the northbound lane assignment by time-of-day. By providing additional capacity for the northbound right-turn movement, particularly during the weekday a.m. peak period, the project will reduce delays, shorten vehicle queues and minimize queuing impacts to adjacent accesses, and help address an existing safety deficiency.
Although South Platte Canyon Road is technically on CDOT’s state highway system, and the roadway serves as the west boundary to the Town of Columbine Valley, with unincorporated Arapahoe County land along the west side of the roadway, the City of Littleton is responsible for maintenance and operation of the existing traffic signal and, thus, identified as the local agency to lead this project. The city is also in the process of developing a separate IGA with CDOT to evaluate, identify, and construct a holistic longer-term solution at this intersection. In the meantime, a dynamic lane assignment system that changes the northbound through lane to a shared through/right-turn lane at certain times of the day has the support of the multi-jurisdictional coalition as an interim safety solution.
A federally-funded grant, as part of the Regional Transportation Operations Improvement Program, distributed by the Denver Regional Council of Governments (DRCOG) and administered by CDOT, helps municipalities fund safety improvement projects. Due to the demonstrated capacity and crash history identified along South Platte Canyon Road at West Bowles Avenue, this intersection is eligible for improvements. The city applied for and received a grant for the installation of the dynamic lane assignment system. Staff’s recommendation is to install this system now as an interim solution until a reconstruction of the intersection can be funded and completed.
PRIOR ACTIONS OR DISCUSSIONS:
The multi-jurisdictional coalition partnered on a corridor study and the intersection of South Platte Canyon Road and West Bowles Avenue was identified as the highest priority location for improvement.
STAFF ANALYSIS:
The capacity limitations and crash history make the South Platte Canyon Road and West Bowles Avenue intersection a high priority for safety improvements. The dynamic lane assignment system may provide sufficient improvement to the north approach operations to allow the long-term intersection solutions to focus on other safety concerns and constraints. The DRCOG grant program provides the city with the opportunity to undertake this project where city funds alone may have not been available.
If council approves this resolution, staff will proceed with hiring a consultant to prepare a final design of the dynamic lane assignment system. Construction of the project is anticipated for the spring of 2019.
OPTIONS/ALTERNATIVES:
The approach along South Platte Canyon Road at West Bowles Avenue has been a congestion and safety concern for many years. If the proposed improvements are not undertaken, the capacity and crash issues are expected to become worse. Staff is hopeful that not only will the proposed dynamic lane assignment system improve conditions as an interim solution, but it could also alleviate problems to the extent that construction of a second right-turn lane is not required. Alternatively, the intersection could continue to operate as is until a more long-term solution can be designed, funded and constructed, likely several years into the future.
FISCAL IMPACTS:
The estimate for the dynamic lane assignment system when the grant was applied for was $54,404. The grant provides for 80% federal funding ($43,524) and 20% local agency match ($10,880). Staff has further consulted with professional expertise in the area of intelligent transportation systems (ITS) and now estimates the project cost at approximately $62,400. Since the funding has already been set for the grant, this would mean an additional $8,000 would be required from the city. Funding will come from the pavement management projects line item in the Capital Projects Fund.
STAFF RECOMMENDATION:
Staff recommends city council approve the resolution and authorize an IGA with CDOT for the installation of a dynamic lane assignment system at the intersection of South Platte Canyon Road and West Bowles Avenue that changes the northbound through lane at the intersection to a northbound shared through/right turn lane.
PROPOSED MOTION:
Proposed Motion
I move to approve a resolution authorizing an Intergovernmental Agreement between the city and the Colorado Department of Transportation for the installation of a dynamic lane assignment system at the intersection of South Platte Canyon Road and West Bowles Avenue.