In October of 1972, the United States Congress passed amendments to the Water Pollution Control Act which required communities to upgrade wastewater treatment facilities. The City of Niles received approval to upgrade its wastewater treatment plant, separate some of the City's combined sewer systems, and construct a new interceptor sewer. Sewer separation work was started in 1976 and completed in 1979. The total cost of this upgrade was approximately $33,200,000 with this cost being shared between the United States Environmental Protection Agency and the City of Niles. The City's $5,200,000 cost was financed through a 20 year bond that was paid off in 1998.
The City has a wastewater treatment plant with an average capacity of 5.8 million gallons per day, of which the City and Townships use approximately 2.5 million gallons. This gives the City a reserve capacity of 3.3 million gallons per day. In addition, the City is aggressively involved in a CSO program to separate portions of its combined sewer system. During the summer of 2004, the entire downtown area was separated at a cost of $750,000.
After more than 40 years of operation, the City's wastewater treatment infrastructure has aged significantly. Operation and maintenance costs have increased greatly and the Michigan Department of Environmental Quality (MDEQ) has raised questions regarding certain Plant processes and the plant's ability to meet its National Pollutant Discharge Elimination system (NPDES) permit. As a result, the City partnered with a consultant engineering firm to conduct a Master Plan study of the City's entire wastewater collection and treatment system. The wastewater treatment plan has had several components upgraded and other components that continue to be part of the treatment process. A coordinated program involving both the collection and treatment infrastructure will allow the City to respond to the issues of the MDEQ.
In 2011, the City of Niles Utilities Department completed a major upgrade to the wastewater treatment plant. The upgrade included new influent pumps, a sodium hypochlorite disinfection system and sludge screw presses.
The City of Niles first provided sanitary sewer service around the year 1900. This first collection system consisted of combined sewers which carried both sanitary and storm water drainage directly to the St. Joseph River. In 1948 an intercepting sewer and a wastewater treatment plant were constructed. In fact, this original plant building still stands today. It intercepted and collected sanitary flow from the combined sewers. The problem with this old system was primarily during storms, storm water mixed with raw sewage and overflowed into the river. In the 1970's our system handled not only the 5 square miles of the city, but also outlying areas.
The outlying areas had new separate storm and sanitary sewers constructed. With these new systems, storm water could drain directly into the river and sanitary water was discharged into the combined sewer system.
With the passage of the Water Pollution Control Act of 1972, communities were required to upgrade wastewater treatment facilities. A new wastewater treatment plant went into construction in 1976 that would be able to handle the needs of the community for the next 20 years. This upgrade included the expansion of the plant, separation of some of the City's sanitary and storm sewers, construction of a new interceptor sewer and diversion chambers and construction of new township sanitary sewers that discharged into the City system.
That first upgrade of the wastewater treatment plant was completed in 1979 and increased the capacity (amount of how much waste water could be processed) to 5.8 million gallons. Today about 2.5 million gallons of wastewater are processed daily. Over the years the combined Sewer Overflow program (or sewer separation program) separated approximately two thirds of the combined sewer area. The remaining area, which was generally located in the downtown district, underwent separation in various phases starting in 2002 and took approximately 7 years. Much of the work was completed during the renovation of the downtown streets.