From
James R. Cummings, Environmental Services Director
Title
Design-build contract with Er-Con, a sole source provider, for repair of the City of Grand Prairie Landfill river levee in an amount not to exceed $545,000, plus a 5% contingency of $27,250 for a total of $572,250
Presenter
Patricia D. B. Redfearn, Ph.D.
Recommended Action
Approve
Analysis
In the mid-1980s, the U.S. Army Corps of Engineers (USACE) constructed a levee that would prevent the Trinity River from intruding upon the City of Grand Prairie landfill. The maintenance of the levee was assigned to the City.
Over thirty years have elapsed, during which, the levee has been maintained by Public Works and inspected by USACE. While there was already river-related impact to the levee at the time, two excessive rainfall events, of May 2015 and November 2015 caused greater damage to the levee. Therefore, the City contracted with Freese and Nichols (FNI) for damage assessment and an alternatives analysis for how best to repair the levee.
FNI collected and evaluated data and provided recommendations to bring the levee back to its original form and function while minimizing future damage. The most feasible option for repairing the levee is a proprietary and sole source system, which will be designed and installed by Er-Con. This method utilizes patented webbing structures that are supported by piers driven deep into the embankment. Collectively, these structures are referred to as a river training system. They will harvest materials from the river which will cause build-up and deposition, while preventing further damage. Additional deliverables of the project include hydraulic modeling for the Palisades structure, the associated Corridor Development Certificate and City permits.
Financial Consideration
Funding is available in the Solid Waste Capital Project Fund, Activity #01508703 (Landfill Levee), in the amount of $1,378,615.