CC MEETING: April 4, 2017
DATE: March 20, 2017
TO: Erin Rinehart, City Manager
FROM: Cesar J. Molina, Jr., P.E., Director of Engineering
Title
Consider A Resolution Authorizing The City Manager To Enter Into A Local Project Advance Funding Agreement With The Texas Department Of Transportation To Construct A Drainage Culvert Under The IH-35E Northbound Frontage Road At Vandergriff Drive In The Amount Of $441,873.25; And Providing An Effective Date.
Body
BACKGROUND:
In July 2014, City Council authorized the design contract for Downtown box culverts from just east of Broadway on Vandergriff to IH-35E. This was a continuation of the drainage system installed as part of the Union Square project and replacement of an old, undersized box culvert. A change order for $17,800 was authorized by Council in September, 2015 to address additional subsurface exploration to locate franchise utility lines on Vandergriff and add sidewalk along Broadway between Vandergriff and 5th Street.
Initially, staff assumed that the construction of the Vandergriff section of the box culverts would coincide with the construction of the IH-35E section with which it connects. As the construction phasing of IH-35E became more clear and defined, it became apparent that access to the Downtown area will be restricted with Belt Line Road, the IH-35E frontage road and Vandergriff (which impacts Elm Street and Broadway). By delaying the construction of the drainage structures on Vandergriff, mobility is improved in the Downtown area by providing reasonable routes around the IH-35E/Belt Line construction activities. A second change order dated May, 2016 for $56,430.00 authorized the consultant to proceed with design changes to allow the de-coupling of the TxDOT portion of the drainage improvements with the City’s Vandergriff project.
A number of modifications are required to accommodate the delay of the Vandergriff project. These include construction of the box culverts a distance up Vandergriff to facilitate grade changes to the frontage road. A large box structure is required where the new pipe meets the existing pipe. This allows the current piping to remain in service until the City project routes flow into the new pipe system. Since this project will be installing some pipe that was originally anticipated for the Vandergriff project, the construction cost of the City’s project will be reduced somewhat. Unfortunately, a major cost of this option, the box at the existing pipes, would not be required without the phasing of the project.
TxDOT’s contractor has submitted a bid of $441,873.25 to build a junction box under the IH-35E frontage road and to extend the three 9’ x 4’ box culverts under Vandergriff by a distance of about 100 feet. About $150,000 of this cost is for box culverts that would have originally been part of the City’s project.
FINANCIAL IMPLICATIONS:
Funding for this project was approved as part of the 2013 Bond Program as the Downtown Drainage Improvements project.
IMPACT ON COMMUNITY SUSTAINABILITY:
This project will contribute to community sustainability by:
• Reducing the potential for flooding in the Downtown area.
• Taking advantage of the improvements to the drainage system in Downtown provided by TxDOT through the IH-35E reconstruction.
STAFF RECOMMENDATION/ACTION DESIRED:
Staff recommends City Council authorize the City Manager to enter into an agreement with TxDOT to fund drainage improvements at a cost of $441,873.25.