Plant History / Profile

In the late 1970s pollution caused by failing septic systems surrounding the waters of Round Lake, Long Lake and the Chain-O-Lakes spurred the necessity for a regional sewage treatment plant in the Northwest Lake County Area.

The Northwest Regional Water Reclamation Facility (NWRWRF) went online in 1979. The original plant was designed to treat 6 million gallons per day (mgd) of waste water from the communities of Fox Lake, Round Lake, Round Lake Beach, Round Lake Park, Round Lake Heights, Hainesville, the Lakes Region Sanitary District and Portions of unincorporated Lake County.

The original plant design incorporated rotating biological contractors (RBCs) as the secondary treatment process for organic removal. In the late 1980s, it became apparent that the RBCs were incapable of providing adequate treatment.

Studies and plans were completed in 1989 to replace the RBCs with an activated sludge process, and provide plant capacity expansion to 9.0 mgd design average flow and 22.5 mgd design maximum flow.

The first phase of construction went online in 1991 and the second phase in 1992.

The upgraded facility meets the effluent criteria established by the Illinois Environmental Protection Agency (IEPA) in the plants National Pollutant Discharge Elimination System (NPDES) permit. The treatment process consist of screw pumps that lift the waste water through three stages, perforated screens, grit removal, primary clarifiers, conventional activated sludge aeration and clarification and rotating disc filters.

Waste-activated sludge is run over two gravity belt thickeners and thickened primary sludge that is pumped from the primary clarifiers into gravity thickeners are combined for digestion in three primary anaerobic digesters. A secondary digester holds the stabilized digested sludge prior to centrifuge dewatering. The dewatered biosolids averaging 24% solids are stored on site in a storage building prior to land application.

Odor control is accomplished by chemical addition in the collection system to control hydrogen sulfide. Three air scrubbers are also used to “polish” the air from the head works, solids-handling area and biosolids storage area.

Distinctive features added to enhance the process since 1992 include perforated screens and washer, vortex grit removal, UV disinfection and a Dystor gas storage system on the secondary digester.

Present Day
In 2006 the facility was awarded the prestigious Illinois Section Treatment Facility Operations Aware from the Central States Water Environment Association. 20 full-time employees comprised of two shifts staff the facility.

Expansion to 12 mgd is expected to start in the spring of 2011. The expansion will address nutrient removal and increase capacity to handle development over the next 20 years.

The NWRWRF is dedicated to protecting the environment through sound operational and maintenance practices.