The North Olmsted Wastewater Treatment Plant (NOWWTP) is located at 23775 Mastick Road next to the Cleveland Metropark's Rocky River Reservation. The NOWWTP is classified as a Class 4 facility by the Ohio Environmental Protection Agency (OEPA).

The treatment process at the NOWWTP is an Activated Sludge process with biological nutrient removal. It is designed for an Average Daily Flow of 7 million gallons per day (MGD),with a Peak Hourly Flow of 40 MGD.


When the flow enters the treatment plant, it goes through screening and grit removal processes, these processes remove non biological material from the wastewater.



The flow is then directed into the biological stage (Vertical Loop Reactors) of the treatment process. This process removes the biological material, reduces phosphorus, ammonia and nitrogen from the wastewater. The biological material must be removed from the wastewater, this is done by final clarification. The NOWWTP has three 105' final clarifiers.

A small portion of the Biological Material must be removed from the process and dewatered. This is done using a high speed centrifugal process (scroll centrifuge). The biomass that has been dewatered is hauled to a recycling facility and used to generate electrical power.

 The final step of the treatment process is tertiary filtration.  Water leaving the  clarifiers is filtered down to a level of 20 microns.  After tertiary filtration the water is disinfected, this is accomplished by water flowing past high intensity ultraviolet (UV) light. The disinfection ends the treatment process, the water is then released into the Rocky River.