Memorandum
City of Lawrence
Public Works
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TO: |
Mike Wildgen |
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FROM: |
Chuck Soules |
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CC: |
Dave Corliss, Debbie Van Saun, Terese Gorman, David Woosley, David Hamby |
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Date: |
December 12, 2005 |
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RE: |
19th & Louisiana Intersection Improvements |
HISTORY: This project has a fairly long history beginning with a study completed in April 2000 by Wilson and Company entitled “The Louisiana Traffic Calming Study”. On July 22, 2003, the City Commission approved Resolution 6478 in the amount of $250,000 for improvements to 6th & Lawrence Avenue, and to begin improvements to 19th & Louisiana. In November 2004 the City Commission approved Resolution 6571 authorizing bonds in the amount of $250,000 for improvements to the intersection of 19th and Louisiana. Currently there is $271,000 authorized budget available after the study is complete. This project is to take multiple years for funding; the Louisiana Traffic Calming Study provided an estimate in 2000 of $545,000.
January 3, 2005 - The project was introduced to Douglas County and the School Board at a joint meeting.
January 18, 2005 – City Commission approves pre-design report to be completed by BG Consultants in an amount of $37,180.08.
March 10, 2005 – Stakeholders meeting with Lawrence High School, Cordley Elementary School and neighborhood associations from Old West Lawrence, University Place, and Centennial.
May 16, 2005 – Held a public meeting requesting input.
October 19, 2005 – Met with school representatives to discuss preliminary report results.
Staff does intend to present the study to the School Board and public when complete. However, since the cost and right-of-way needs exceeded what was anticipated it is appropriate to have the City Commission review the status of the project and perhaps consider narrowing the possible range of improvements.
PRELIMINARY REPORT RESULTS/STATUS
- Crash rate for the intersection is 11.51 c/tmev (crashes/ten million vehicles entering the intersection). This is the highest crash rate for intersections in Lawrence, and very near what the State considers a critical crash rate for intersections of this type (11.69 c/tmev).
- The Level of Service (LOS) of the intersection at peak times is E, some approaches operate at LOS F.
- The Level of Service is measured in terms of seconds a vehicle has to wait (or is delayed). The following table identifies those times:
Table 16-2: Level-of-Service Criteria for Signalized Intersections
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Level of Service |
Average Control Delay (s/veh) |
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A |
0-10 |
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B |
> 10-20 |
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C |
> 20-35 |
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D |
> 35-55 |
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E |
> 55-80 |
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F |
> 80 |
- Pedestrian crossing peak time is between 2:30 and 2:45 p.m. with 85 pedestrian crossing movements.
- Two preliminary options have been developed with pros and cons of each option listed (see attached preliminary report). The two preliminary options are:
- Geometric improvements – Primarily, this option would require significant property acquisition. The construction estimate uses Douglas County appraisals for acquisition. The base project is $2.3 million. Alternatives for bus turnout lane and left turn lane on 19th Street, west of Louisiana, brings the estimate to $2.4 million. Realistically, with increases in construction costs and property values, this option will approach $2.5-$3 million.
- Roundabout Option – Primarily, this option would require less property acquisition. The base estimate is $1.5 million. With a bus turnout lane and left turn lane on 19th Street, west of Louisiana, the estimate is $1.7 million. Again, realistically this is a $2 million project. Of concern is the projected 2015 traffic volumes for which the V/C ratio (Volume to Capacity) for the roundabout is at capacity during peak periods.
OTHER IMPROVEMENTS (cost estimate attached)
- Reconstruct the southeast corner radius to facilitate turning movement. Increasing this radius will require additional right of way and signal relocation. The estimated cost is $111,308, not including right-of-way or utility relocations. This improvement would make the right turn from Louisiana to east bound 19th Street easier for motorists, however would not significantly affect the overall performance or safety of the intersection. The cost of this improvement does not warrant the minor improvement in vehicular movements.
- There are a significant number of angle accidents from left turning vehicles not yielding the right-of-way during a permitted left turn movement (nine (9) crashes due to westbound left-turn failing to yield to eastbound traffic). One solution would be to remove the permitted left turn phase for 19th Street and provide a longer storage lane east of Louisiana. This improvement requires widening 19th Street at the Ohio Street intersection to accommodate a 3-lane section. Restricting left turns onto Ohio during the peak hour should be considered with this improvement. The widening may be possible to the north.
Discussion: Providing a protected left turn lane can reduce accidents; however, delays during the peak hour will increase. Traffic currently experiences backups onto Tennessee. Adequate storage for this turning movement is not available today, nor would this improvement provide sufficient storage at peak times. Estimated cost of engineering/construction is approximately $160,455, not including right-of-way or utility relocation.
- Addition of a bus turnout lane south of the intersection to facilitate bus loading/unloading to alleviate traffic congestion. This improvement would not improve the safety of the intersection, however public comments received view this issue as an obstacle to traffic flow on Louisiana. Total cost of engineering/construction would be approximately $35,000 - $40,000. This improvement would improve traffic flow during school, however does not have a significant effect on the safety of the intersection.
- Widening of 19th Street west of Louisiana to provide a center turn lane. This widening could be extended west to the high school’s western most entrance. The improvement would facilitate ingress/egress from Lawrence High School and provide storage for the intersection. Entering and exiting the high school was also an issue expressed at the public meeting. It would be recommended that the eastern most exit become a right-out only to preserve the storage for the intersection. Similar to the center turn lane on 6th Street, this would provide an area for turning vehicles to get out of the lane for through traffic. There may be sufficient right-of-way on the south side of 19th Street, however significant Westar facilities would need to be relocated. This would be at the utility’s cost and would take several months. The sidewalk would also need to be reconstructed. The estimated cost is approximately $287,483, not including right-of-way or utility relocation.
The estimates provided are for street improvements only. The city
has significant water lines in this intersection which will need to be
evaluated to determine if they would also need to be replaced.
Recommendations:
The proposed intersection reconstruction projects, both the geometric and roundabout options, have exceeded expected financial and right-of-way requirements. Because of the cost and lack of long term benefit, staff does not recommend pursuing either the roundabout or the geometric improvement options.
As discussed, providing a left turn lane on 19th Street westbound could improve the safety of the intersection (reduce the number of accidents) and, therefore, should be pursued.
Additionally, should the City Commission desire, traffic flow in the area could be improved with a bus turnout lane on Louisiana Street and a center turn lane on 19th Street from Louisiana Street west to the western school property line.
Action Requested: Provide staff direction on improvements to be presented to the School Board and the public.
Respectfully submitted,
Charles F. Soules, P.E.
Director of Public Works