Saddle Creek Retention Treatment Basin

The purpose of the Saddle Creek Retention Treatment Basin (SCRTB) Project is to capture combined sewage and store or treat it during wet weather events. Combined sewage will be diverted from the Saddle Creek Sewer and conveyed to the SCRTB headworks, where large materials like cans, rocks, tree branches and floatable solids are removed using a grit pit and mechanical screens. Directly following screening, a disinfectant will be added to the combined sewage flows to kill or inactivate bacteria. The 3.3 million gallon basin will allow for solids to settle and be removed from the combined sewage. For small wet weather events, the combined sewage will be fully captured (retained) in the underground basin. For larger events, the underground basin will completely fill up and a dechlorination agent will be added just prior to flows discharging through an overflow channel to the creek.

When construction is complete, the RTB will capture and treat a combined sewage flow rate of up to 160 million gallons per day. The headworks and chemical storage and feed systems were designed to meet peak instantaneous flow rates up to 320 million gallons per day to allow for large flow variations into the basin and also the potential for treating higher flows in the future. The RTB will use dewatering pumps to empty the facility after a wet weather event has ended. These pumps will convey captured combined sewage volume into the downstream Papillion Creek Interceptor sewer for treatment at the Papillion Creek Water Resource Recovery Facility (PCWRRF). A new 60-inch gravity sewer was installed around the RTB facility to provide increased CSO flows to be conveyed to the PCWRRF at the onset and over the entire duration of a wet weather event.

The above ground improvements included a building to house controls, grit and screening equipment, and chemicals. The building will provide office space for full-time operations staff, some additional city offices and maintenance for the facility. This project will also include work in the Saddle Creek outfall channel to complete the improvements with energy dissipation structures and natural channel elements at the confluence with Little Papillion Creek.

An odor control system will be installed to address the risk of odors from the facility. The site will include fencing and lighting for security purposes.