Title
Consideration of and action on authorization for Ardurra proposal for the Wastewater Treatment Plant digester structure evaluation.
Body
Summary:
The digester at the Deer Park Wastewater treatment plant was constructed in 1970s. The City recently hired Terracon who conducted a visual inspection of the exterior of the digester and reported vertical cracks in digester basin concrete walls, leakage of liquid through several vertical cracks and vertical joints between walls at corners of the digester, and exposed aggregate on the interior side of walls facing wastewater sludge. The basin structure has been in service for nearly 50 years and the effectiveness of implementing repairs on the exterior side to protect the concrete walls is limited.
At the recommendation of Terracon, the City desires to remove the digester from service to allow for inspecting the structure in order to determine the future rehabilitation scope, estimate cost opinion, and anticipated rehabilitation schedule. It is anticipated that each of the three digester cells will be taken offline one at a time for inspection.
Staff is recommending the study be performed by Ardurra, who has done work previously for the City and recently completed a similar project for the City of Galveston. The total cost of the inspection and evaluation is $101,199.00.
Fiscal/Budgetary Impact:
Add $101,500.00 to the Fiscal Year 2022-2023 Water & Sewer Fund Budget for the Wastewater Treatment Plant (Account No. 400-502-49040, Machinery & Equipment) to be funded from the prior year revenue (fund reserves) in the Water & Sewer Fund, which is available for this purpose.
Recommended action
Authorize the Ardurra proposal for the Wastewater Treatment Plant digester structure evaluation.