|City of Nokomis
City of Nokomis- Wastewater Treatment
Nokomis, Illinois 62075
As far back as 1914, the original waste water plant was located at the west end of Hamilton Street at the
present site of the city brush dump.
In 1952, a new plant was built on the present site at the west end of Hamilton Street, just northwest of the
In 1985, the plant was expanded to a 20 acre facility with treatment processes including primary
treatment, aerobic sludge digestion, one 1.25 acre, 7 million gallon capacity primary treatment aerated
lagoon and one 3 acre, 10 million gallon capacity flow lagoon featuring two intermittent sand filters. The
Nokomis Wastewater Plant is a class III trickling filter/lagoon treatment system.
The plant tests water two days per week in their lab for suspended solids, ammonia nitrogen, pH and
biochemical oxygen demand. The Illinois EPA tests the effluent from the Nokomis plant monthly. The
plant is also in a testing program monthly with P.D.C. Laboratories of Peoria, Illinois to confirm the plants
The plant is semi-automatic, running 24 hours a day with the plant manned 8 hours per day, Monday
through Friday and 4 hours on Saturday and Sunday each week. The plant has the capability to jet-rod
(clean) their system, televise and/or repair. They have state-of-the-art equipment to safely work and
monitor the system.
The capacity of the primary treatment plant is a normal flow of 360,000 gpd (gallons per day) with a
maximum flow of 900,000 gpd. The flow for the year 2004 was 130 million gallons of treated waste water
in full compliance with Illinois state requirements. This flow generated 189 dry tons of sludge that was
disposed of by land application on nearby farm fields with the treated water flow discharged into Shoal
Creek, which flows to the Kaskaskia River and then later empties into the Mississippi River south of St.