Ingersoll Avenue Reconstruction from Polk Blvd to 42nd St
Reconstructing Ingersoll Avenue From Polk BLVD to 42nd St: A Project Overview
Currently, Ingersoll Avenue between Polk Boulevard and 42nd Street includes a drive lane in each direction, a continuous left-turn lane, bike lanes in each direction, and on-street parking on both sides. To comply with the City's Complete Streets Policy and meet current traffic and parking needs, the two-way left-turn lane and parking on one side of Ingersoll Avenue will be repurposed. The new street configuration will include drive lanes in each direction, on-street parking on the north side, and buffered bike lanes in each direction. These improvements provide a consistent corridor to connect the improvements currently under construction from MLK to 24th street associated with the Streetscape improvements. Existing sidewalks will be reconstructed. The new sidewalk will be constructed to fill in missing gaps to provide a continuous walking path. The project also includes improvements to underground utilities.
Project Purpose and Goals
Engineering & Research Internation, Inc. (ERI) conducted a pavement evaluation analysis in 2016 that identified this section of Ingersoll Avenue to need full reconstruction. The City hired McClure Engineering Co. to study the existing traffic and parking use on Ingersoll Avenue and to review how the current and future parking and traffic needs would fit with the City's Complete Streets Policy. The study of traffic data found the two-way left-turn lane was unnecessary to meet turning movements and that peak parking along the corridor could be accommodated with parking on only the north side of Ingersoll Avenue. The new roadway section will reduce the crossing distance to improve pedestrian safety. The existing bike lanes on Ingersoll Avenue are not buffered and do not meet the Complete Streets Policy. Buffered bike lanes are proposed for this public improvement project. The existing stormwater collection system does not meet current design standards and will require improvements including permeable pavers in the on-street parking lane.
City of Des Moines Engineering Department - Project Engineer
Project Conceptual Documents
When will construction take place?
Reconstruction of Ingersoll between Polk Boulevard and 42nd Street is anticipated to begin in the spring of 2021 and be substantially complete in the fall of 2021. Supplementary landscape restoration work may be required in the spring of 2022 to fully complete the project.
Streetscape improvements and roadway reconstruction of Ingersoll Avenue between Martin Luther King Jr Parkway and 31st Street is currently underway and will continue for the next several construction seasons. Improvements to Ingersoll Avenue between 31st Street and 42nd street are currently being planned to provide a consistent corridor but are not yet incorporated into the city’s 5-year budgeting plan.
Will roads be closed during construction? Will I have access to my driveway?
Ingersoll Avenue between 42nd Street and Polk Boulevard will be closed to thru traffic. Road closures and detour routes will be posted on the Road Closure Map on the City's website. Construction will be staged to maximize access to driveways for local traffic. Driveways within the project will not be accessible during limited portions of construction. If necessary, special accommodations and/or coordination will be made during construction to assist residents with mobility requirements.
During construction, solid waste collection services will be continued as normal. Mail service will be maintained.
Residents are encouraged make any needed repairs to their water and sanitary sewer services prior to the construction of the new street pavement. It is anticipated that these will reduce the need to remove any of the new roadway pavement after the project is complete.
How much will it cost?
The estimated construction cost is $2.75 million. A portion of that cost, $1.0 million, will be paid for using Iowa Department of Transportation funding. The remainder was programmed as part of the City's Capital Improvements Project (CIP) budget. There will be no special assessment for this public improvement project.
Who do I contact if I have questions?
City of Des Moines Engineering
Responses to questions
Public Meeting Questions and Responses
Ingersoll Avenue from 42nd Street to Polk Boulevard
Concerns about eliminated parking along Ingersoll on the south side between 42nd Street to 43rd Street.
The City has conducted additional data collection and field observation related to the on-street parking on this stretch of Ingersoll Avenue. Based on the additional data collection the City plans to include on street parking on the south side of Ingersoll Avenue between 42nd Street and 43rd Street.
Questions were raised regarding 11-foot travel lanes vs. 10-foot travel lanes.
City staff discussed this topic with DART staff and further explored the pros and cons of each travel lane width. While 11-foot travel lanes are preferred by DART staff, the presence of the striped buffer would allow operational flexibility and make them to be comfortable with a 10-foot travel lane. The City also prepared the below exhibit to better illustrate the differences between the two lane widths.
In the City of Des Moines, the double yellow line is made of two, 4 inch lines separated by a 6 inch space. On Ingersoll Avenue, the travel lanes are proposed to be constructed with asphalt while the buffer and bike lanes are proposed to be concrete. When considering the double yellow centerline the useable lane width for an “11-foot” travel lane is 10’-5” and 9’-5” for a “10-foot” travel lane. The usable width is calculated by subtracting half the centerline marking width (7 inches).
The figure below shows how emergency vehicles, buses and passenger vehicles would fit within the lane provided. Because the travel lane is made of different material than the buffer and bike lanes, there is a pavement joint on the edge of the travel lanes. For maintenance purposes it is preferred to not have pavement markings or joint lines in the wheel path of vehicles. It is City Staff’s recommendation that the measured lane widths for this corridor be 11-foot.
Number and location of DART stops.
City staff met with DART staff to discuss the possible consolidation and treatment of stops along this corridor. DART agreed that stops along this corridor could possibly be consolidated. DART is analyzing stop locations and frequency and will be recommending changes within the next few weeks. DART’s recommendations will be incorporated into the final design plans. Stop locations will utilize proposed bump-outs to improve loading/alighting.
Questions whether the speed limit should be reduced from 30 mph to 25 mph.
The City’s current process for establishing or modifying a speed limit begins with an engineering study of the corridor which includes collection of speed data including the 85th percentile speed, the speed at which 85 percent of the vehicles are driving at or below. City staff reviewed this section of Ingersoll Avenue using other evaluation methods for setting speed limits including USLIMITS2 and the Credible Urban Speed Zone model. These methods include evaluation of the free-flow speed as well as crash experience, street characteristics, street context, and street user. The current speed limit of 30 mph was found to be appropriate by these methods.
Staff does not recommend that the speed limit on Ingersoll Avenue from 42nd Street to Polk Boulevard be changed at this time. The engineering studies conducted indicate that the appropriate speed limit for this corridor is 30 mph. Lowering the speed limit does not mean that travel speeds will decrease. City staff does however believe that the reduction in pavement width, removal of the two-way center turn lane and the contrast between the two different pavement materials for the travel lanes and buffered bike lanes may result in reduced speeds. An engineering study will be performed when the proposed geometric changes are completed and traffic normalizes to reevaluate whether a speed limit change is warranted.