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/ Services / Wastewater

(641) 435 - 4156



Wastewater (sewer) services are contracted through Ion Environmental Solutions. You can contact their 24-Hour Customer Service Department by calling Chad McCleary 563-299-2214. 

  24-Hour Customer Service  



If a sewer backup occurs in your house or building, first check to see if it backs up only when you use your facilities such as stool, tub, washer or sinks.  If so, it is a possibility that you need a plumber.  If you have sewage backing up when you have not used any of the facilities, it is a possibility that there is a blockage in the City's main.   



After contacting the customer service center, Ion Environmental Solutions will respond and check the public main to determine if it is causing the sewer backup.  If the public main is operating normally, indications are that your private sewer service is the cause of the sewer backup. If the blockage is in the private service line to house or building, it is the responsibility of the property owner to clear the blockage. The private sewer service line extends from the house or building to the City's sewer main. 


Treatment Plant

The City of Nashua operates and maintains a Grade III activated sludge sewage treatment plant for its wastewater.  The Wastewater Treatment Plant is nestled along the Cedar River near the southern city limits.


Wastewater services are contracted with Peopleservice, Inc. Peopleservice staff measures and reports monthly on eighteen (18) different parameters to the Iowa DNR for both influent and effluent. Other major work elements include maintenance and operation of the treatment plant facility, lift stations, and equipment; sewer main repairs and preventative maintenance, line cleaning and inspection, and 24/7 response to emergency sewer calls. The city owns a vacuum truck used primarily for sewer line maintenance such as clearing obstructions and routine cleaning.


Two lift stations are utilized throughout the city to aid the flow of wastewater through the nearly 10 miles of sanitary sewer lines to the treatment plant. The two lift stations were installed in 1963 and 1975.


At the treatment plant, wastewater is pumped to the Headworks building from a lift station upon entering the facility. The wastewater passes through a step screen and a grit removal chamber to remove solids, non-biodegradable items, and grit. The waste travels through a metering system and is sent to two aeration tanks. Organics are naturally removed in the aeration tanks. Clarifiers remove sludge which is sent to a digester, a holding tank, and ends up in one of four reed beds. Following the clarifiers, the clear wastewater travels through a contact chamber where the water is treated with Chlorine to kill E-coli, and Sulfur Dioxide to kill the Chlorine. Chemicals are only used in the disinfection process March through November. The clean and disinfected water is discharged into the Cedar River.


Wastewater volume is continuously monitored and extensive regular testing is completed throughout the entire process to comply with conditions of the DNR operating permit and protection of our ecosystem and natural resources. The Wastewater Treatment plant is regulated by the IDNR (Iowa Department of Natural Resources).


The average flow to the treatment plant during 2015 was 4.16 million gallons per month. The facility is designed to process an average of 122,000 gallons per day in winter months and 230,000 gallons per day during wet weather seasons. The plant discharged 49.9 million gallons of treated water into the Cedar River in 2015.

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