As water supply is quickly diminishing due to high seasonal demands, Huntsville Utilities is proactively finding solutions to mitigate water scarcity concerns. The Utility currently operates two surface water treatment plants that treat water from the Tennessee River. The Utility decided to begin planning for a third surface water treatment plant. As a trusted consultant to Huntsville Utilities, Tetra Tech was selected to provide site selection, design, permitting, and construction management services for the new $90M Huntsville Utilities Southeast Water Treatment Plant.

Tetra Tech performed a site selection study, which recommended a new raw water intake be located on Guntersville Lake and that property be purchased north of the site for the construction of the new water treatment plant site. In addition, Tetra Tech assisted Huntsville Utilities with obtaining the necessary permits from the Tennessee Valley Authority.

The design for the new surface water treatment plant includes provisions for disinfection byproducts formation control to ensure compliance with the Stage 2 Disinfectants and Disinfection Byproducts (DBP) Rule. Tetra Tech performed a bench and pilot study at the site of the existing South Parkway Water Treatment Plant to test a number of different treatment technologies for DBP control. 

The new surface water treatment plant will be constructed on a 266-acre site and will have an initial capacity of 12 million gallons per day (MGD) and 24 MGD after the filters are rerated in accordance with state criteria. The master plan for the treatment plant will allow for a total build-out capacity of 96 MGD.

Tetra Tech’s design included the raw water intake structure (initial and expanded capacity), conventional surface water treatment facilities with DBP control, on-site residuals management facilities, and a laboratory and administration building. Tetra Tech also designed the supporting infrastructure including clearwell and high service pumping facilities; three and half miles of parallel 42-inch ductile iron pipe (DIP); raw water transmission mains; and seven and half miles of parallel 48-inch DIP finished water transmission mains including approximately 600 feet of 60-inch jack and bore of US HWY 431.