The Duck Creek Wastewater Treatment Plant is an Activated Sludge and Trickling Filter/Solids Contact (TF/SC) plant permitted to treat 40 million gallons per day. The Texas Commission on Environmental Quality (TCEQ) limits discharge of treated wastewater that contains less than 10 milligrams per liter (mg/L) of carbonaceous biochemical oxygen demand, 15 milligrams per liter (mg/L) total suspended solids, and seasonal ammonia nitrogen limits of 5 milligrams per liter (mg/l) (December - March) and 2 milligrams per liter (mg/l) (April - November). During 2015 the average daily results were; 2.4 mg/L carbonaceous biochemical oxygen demand, 3.5 mg/L total suspended solids, and seasonal ammonia nitrogen 0.6 mg/L December - March and 0.5 mg/L April - November.
Treated effluent is discharged into Duck Creek, then to the East Fork of the Trinity River and ultimately to the Trinity River, and ultimately into the Gulf of Mexico via the Houston Ship Channel. During dry months, the river may be composed of up to 95 percent wastewater, and performance of the Duck Creek Plant is critical to the Trinity's health and usefulness as a drinking water and fishing source for those downstream.
All solids (sludge) settled at the Duck Creek Center are pumped via twelve-mile sludge transfer pipeline to the City’s Rowlett Creek Wastewater Treatment Plant with ultimate disposal in the City of Garland's Charles Hinton Jr. Landfill.
In 2015, the Duck Creek Wastewater Treatment Plant treated an annual average flow of 27.97 million gallons per day of effluent wastewater. The facility has received several Gold and Silver Awards, most recently Gold Awards for 2014 and 2015, from the National Association of Clean Water Agencies (NACWA) in recognition of its complete and consistent national pollutant discharge elimination system permit compliance. In 1989, the plant was recognized by the Environmental Protection Agency for “Excellence in Operations and Maintenance”.