To: Honorable Mayor and Members of Town Council
Through: David L. Corliss, Town Manager
Dan Sailer, PE, Director of Public Works
From: Ryan Germeroth, PE, Assistant Public Works Director
Title
Update on Construction Planning for the Wilcox and South Street Roundabout
Body
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Executive Summary
The purpose of this memo is to provide Council with an update on the construction planning effort underway for the Wilcox and South Street roundabout. Construction is slated to start this Spring. A roundabout improvement was first recommended as a part of the Downtown Mobility Master Plan, which was developed during 2018 and formally adopted in 2019. A roundabout is not only expected to improve safety and efficiency for vehicle movements, but also improve the safety for pedestrians, provide low environmental impacts by reducing traffic delays and gas consumption for drivers, as well as enhance the aesthetic environment by providing opportunities for future public art within the center median. All are in-line with the value the community desires from our transportation assets. The Town has partnered with Confluence Companies as part of the Encore Redevelopment Agreement to complete the design of the roundabout. With the plans complete, the developer will be obtaining a contractor with the concurrence of the Town for the construction of the intersection improvement. The construction contract will be brought to Council in early April for concurrence.
During the construction planning process, two main construction options have been considered. One option would fully close the intersection, which would allow the construction to be complete within four months. If there are no weather delays or other unexpected items that impact the schedule, this option could be completed in three months. This option would also simplify the traffic control needed for the project. The result of this option is projected to save the project about $175,000. The detour routing exhibit for the full closure can be seen on Attachment A.
The second option would construct half of the intersection at a time and would result in a construction time of six months. If there are no weather delays or other unexpected items that impact the schedule, this option could be completed in five months. This option would require more set up and take down of traffic control and an additional two months to complete. Due to this, the cost of this option is expected to be approximately $175,000 more than the full closure option. The detour routing exhibit for the partial closure option can be seen on Attachments B and C.
Of the two options discussed here, the full closure option has been the preferred option for surrounding businesses, the developer, and Town staff given the time and cost savings as well as the reduced impact to the traveling public and reduced impact to businesses.
The proposed traffic control plans for both options require one early action item to occur during the month of March. As shown on Attachments A and B a temporary connection is proposed to be constructed to tie Phelps Street into Perry Street. A temporary traffic signal will also be included for traffic control at this new intersection. This connection is needed and will be beneficial for two reasons: First, the connection will provide a more direct and efficient detour route between Wilcox and Perry. Second, South Street is expected to still be closed into the early part of the construction of the roundabout since the new parking garage on the Encore property won't be done until around the middle of April. The temporary connection at Phelps will help to mitigate that impact. The library and church adjacent to Phelps have been contacted and are in support of the temporary connection. In addition, the Town Parks Department will assist with the relocation of several existing trees where the new pavement will be installed and two utility companies will be lowering their underground communication lines. This work on the installation of the temporary connection could begin as early as March 3rd.
Finally, the project team has developed a construction timeline for key project milestones that utilize the full closure option. The full timeline can be seen on Attachment D. Some key items from the timeline include early construction of the Phelps connection in March, Council concurrence of the construction contract occurs in early April, the beginning of full construction begins shortly after that, and the project is expected to be done by August 1st should weather or unexpected conditions occur
Budget Impact
The current project budget is $1,850,000 for right-of-way acquisition, design, and construction. The current engineer's cost estimate for the project plus 10% contingencies is $1,825,890. If the partial construction option is used this would put the project cost at $2,005,851.16, above the budgeted amount by about $150,000. Therefore, the partial closure is not recommended.
Staff Recommendation
Staff is recommending to follow the proposed timeline in Attachment D. This would result in early construction work at Phelps in March and a full closure of the Wilcox and South intersection starting in April and continuing on through early August.
Attachments
Attachment A: Exhibit 1 - Full Closure Detour Plan
Attachment B: Exhibit 2a - Partial Closure East Side Detour Plan
Attachment C: Exhibit 2b - Partial Closure West Side Detour Plan