Memorandum
City of Lawrence
Public Works
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TO: |
Charles Soules, P.E., Director of Public Works
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FROM: |
Zachary D. Baker, E.I.T., Project Engineer
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CC: |
David P. Cronin, P.E., City Engineer Mark Thiel, Assistant Public Works Director
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Date: |
November 1, 2012
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RE: |
Project PW1212 – 9th Street – Tennessee Street to Kentucky Street Mill & Overlay, Pavement Marking, Traffic Signal Improvements
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The 9th Street project original design installs a new center turn lane and bike lanes to be striped on 9th Street between Tennessee and Kentucky Streets. The center turn lane will improve traffic flow through the corridor as no thru lanes will be delayed from vehicles making left turns. The bike lanes were recommended by the bicycle advisory committee and approved at their October 11, 2011 meeting. This additional one block of bike lanes will extend the existing bike lanes to the west. To accommodate the center lane addition with existing dual through lanes and bike lanes in each direction, parking on the south side of 9th Street will need to be removed. A parking study was conducted for this project. It shows the utilization of parking stalls in this corridor is significantly lower than the downtown area. The parking study is enclosed with this report.
To maintain on street parking on the south side other options have been explored.
The first option shares the same 5-Lane section as originally proposed, however, on-street parking would remain on the south side of 9th Street instead of an eastbound bike lane. Lane widths would be 10 feet wide and parking spaces would be 8 feet wide. Widening of the roadway would be required by 3 feet to the south with new pavement, curb and gutter, storm sewer adjustments, sidewalk replacement, and the relocation of a gas line to allow for on-street parking remaining. The estimated additional cost to widen the road is $28,000. Gas line relocation would be at no cost to the city.
There is a concern about leaving parking through the corridor with this lane configuration and the speed of cars. The 9th and Tennessee corridor is posted at 30 mph. Higher speeds and narrow lanes combined with a lower driver expectation of pedestrians and parked cars could potentially be an unsafe situation. Parked car doors will open into traffic lanes. Existing conditions have wider lanes with parking adjacent to them. There is more room for cars to maneuver around an open parked car door. Parked car doors will encroach into the right thru lane with the new design.
The second alternate cross section has two 10.5-foot wide thru lanes westbound, a 10.5-foot wide center turn lane, a single 10.5-foot wide thru lane eastbound, 5-foot wide bike lanes in each direction, and parking available on the south side of 9th Street. This option would not require any roadway widening, however, pavement marking changes would need to be made west of this project to shift eastbound traffic into a single lane before reaching the 9th and Tennessee intersection as there would only be one receiving thru lane just east of the intersection. The additional cost of striping changes west of Tennessee would be relatively minimal.
Intersection Capacity Analysis
Traffic counts were taken during AM and PM peak hours October 25, 2012 and an analysis of how the corridor and intersections would be affected by the lane removal was performed for both alternates.
First, existing conditions were modeled to be compared with both alternate designs. Existing "Level of Service" (LOS) for both the Tennessee and the Kentucky intersection of 9th Street are currently at acceptable levels. A LOS of “A” is optimum and a LOS of “E” or greater is considered unacceptable. Both intersections are at about 70% capacity which results in a capacity LOS of a “C” rating. This is an acceptable rating, which means that traffic volumes can increase and the intersections would still function at an adequate level.
Next, Option 1 was analyzed. Intersection capacity levels did not improve, however, they did remain near the 70% capacity level which is the same as existing conditions.
Last, Option 2 was analyzed. Both intersections became closer to full capacity. Tennessee and Kentucky intersections capacity rose to 74.3% and 89.1% respectfully, therefore, resulting in capacity LOS ratings of “D” and “E” which are approaching the unacceptable range. This increased capacity level means the intersections are closer to saturation levels. Once intersections become saturated (100% capacity), future traffic volume growth will cause intersection delays and poor levels of service. It should be noted that new development in the downtown area in the near future will likely increase traffic volumes through this corridor.
Complete Streets Policy
The addition of bike lanes to this project was proposed to help connect current bike lane corridors on 9th Street. 9th Street west of this project currently has bike lanes on the north and south sides of the roadway. Including them with this project would further extend these lanes closer to the downtown district. Adding bike lanes is a way to comply with the City of Lawrence Complete Streets Policy that was approved in March of this year. This project, no matter which design option is adopted, incorporates several of the Complete Streets Policy elements.
In 2009 the city’s Overlay Program included milling and overlay improvements on 9th Street from Iowa Street to Tennessee Street. At that time the existing roadway between Indiana Street and Tennessee Street consisted of two thru lanes in each direction with on street parking. The City Commission decided to remove on street parking and include bike lanes on both the north and south side of 9th Street.
Summary/Recommendation
There are three proposed design options for the 9th and Tennessee project. The original design includes a 5-Lane section with bike lanes on either side of the road. This option requires the removal of seven parking spaces on the south side of 9th Street. Levels of service and capacities of the intersections would remain relatively close to existing levels. A parking study conducted for one week in September showed that of the seven spaces available, only one was occupied, and for 2% of the time. The total cost for this option is approximately $165,000, 90% of which is paid for by KDOT and 10% is paid for by the city.
The first alternate design Option 1 is a 5-Lane section with that would include everything the first option had but with the ability to keep parking on the south side of the 9th Street. This 5-Lane section would require the roadway to be widened three feet. This option would cost the city an extra $28,000 to construct. No eastbound bike lane would be provided.
The second alternate design Option 2 is a 4-Lane section. This removes a lane of traffic going eastbound on 9th Street. It does allow for the 7 parking spaces to remain on the south side of 9th Street and includes an eastbound and westbound bike lane. Minimal extra cost to the project would be required to build this option. Intersection capacity levels would increase with the 4-Lane section and could potentially cause future levels of service to become unacceptable with traffic volume growth.
Because parking on the south side of 9th Street has a very small utilization, and since it incorporates more of the Lawrence Complete Streets elements with no extra cost, it is recommended that the original proposed 5-Lane section be constructed. Alternate Option 1 brings intersections in the corridor closer to capacity saturation. Alternate Option 2 incorporates everything but requires a $28,000 cost increase that would be 100% city funded.
Project Schedule
Completion of plans: November 2012
Advertise and bidding: December 2012
Anticipated Start Date: Spring 2013
Project Completion Date: August 16, 2013.
City staff is currently working on final design of the project. Engineering Design and construction plans are near completion. Plans are expected to be complete by November 2012 with a letting date in December 2012. Construction will begin in Spring 2013.
Action Request
1. Adopt on first reading, Ordinance No. 8815, removing street parking on the south side of 9th Street between Tennessee Street and Kentucky Street.
2. Authorize the Mayor to sign the City/State Agreement for this project.
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