Wastewater Treatment Plant History

The City of Fairfield Wastewater Treatment Plant (WWTP) is rated as a Class IV Treatment Facility by the Ohio Environmental Protection Agency. Currently the plant treats an average daily flow of 5.5 Million Gallons a Day (MGD) and has a permitted capacity of 10 MGD. The treatment plant is an Activated Sludge plant with Anaerobic Sludge Digestion, producing a Class-B Biosolid. The nutrient filled Biosolid provides numerous farms in Butler County with an excellent fertilizer.


A 2 Million Gallon per Day (MGD) Treatment Plant and Collection System was constructed to serve the City of Fairfield, Ohio. The original plant was a very basic treatment facility consisting of a Pumping Station, two Primary Settling Tanks, two Activated Sludge Aeration Tanks, a Secondary Settling Tank, two Anaerobic Digesters, and 8 Sludge Drying Beds.

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It was necessary for the treatment facility to expand to treat daily flows of up to 6 MGD. A second  Pumping Station was constructed, additional Primary Settling Tanks and Activated Sludge Aeration Tanks were built, a Filtration Building was added, two more Anaerobic Digesters were built, and a Chlorine Stabilization System was constructed to disinfect the plant’s effluent.

In 1974 Congress enacted the Safe Drinking Water Act (SDWA) (P.L. 93 to 523, 88 Stat. 1660) to protect quality of both actual and potential drinking water in the United States. This drastically changed the standards of operations of water and wastewater treatment plants around the country. 


The secondary treatment system was upgraded by building two new Clarifiers  to treat a design maximum flow of 10 MGD. A Sludge Thickening Building was constructed with a Dewatering Gravity Belt Thickener. Also a Fine Bubble Aeration System was installed to enhance the Activated Sludge treatment process, and reduce energy consumption dramatically. The City of Fairfield was the first treatment facility in the United States to take advantage of the advanced Fine Bubble Aeration Technology.


A Klampress was installed in the Thickener Building. This allowed the facility to move to a solids handling program from a liquid removal program. The press’s final product is a nutrient filled Class B Biosolid which provides numerous farms in Butler County an excellent fertilizer. The installation of the Klampress reduced sludge hauling costs dramatically.


The facility’s 3 equalization basins were constructed, giving the facility 10 million gallons of storage capacity which can be utilized during high flow events caused by heavy rainfall.


The facility received a hydraulic upgrade to the Primary System and Flow Distribution Chamber which allowed the plant to be re-rated to a permitted capacity of 10 MGD. Upgrades to the plant’s Grit Collector were completed. Fixed lids were installed on Anaerobic Digesters 1 and 2, providing better insulation, more storage capacity, and a better all around anaerobic process. A new plant boiler was also installed which uses the methane gas created by the Anaerobic Digestion Process to satisfy the facility’s need for heat.


The facility switched from chlorine disinfection to ultraviolet light disinfection. Ultraviolet light is the natural, environmentally friendly alternative to chemical disinfection. Also a more efficient blower which provides air to the Activated Sludge Process was installed saving on energy consumption.


The Secondary Treatment System received a hydraulic upgrade creating a smoother path for the systems final effluent. Also the facility’s Parshall Flume was upgraded to a 3 foot flume which has a flow capacity of 43 MGD.


The facility conducted a Bio Win study. Bio Win is a cutting edge computer software that data is entered into which generates a model of a Wastewater Treatment Plant’s biological and mechanical process. The data entered into the software is specific to our Treatment Facility. Tank capacities, dissolved oxygen levels, plant flows, and plant flow characteristics are a couple examples of the data entered into the software. The research project was very sample intensive. Samples were collected throughout  the plant’s treatment process, and tests were run on the samples to determine certain characteristics such as phosphorus, ammonia, and BOD amongst many other parameters. The study was conducted in anticipation of the Ohio Environmental Protection Agency (EPA) setting  limitations on phosphorus and total nitrogen for the plant’s final effluent. When the Ohio EPA does set limitations, the facility will have to go through a major upgrade, tankage will need to be added, and process will need to be implemented in order to treat phosphorous and total nitrogen biologically.


The facility upgraded its SCADA System to Rockwell Control Logics. The upgrade was performed in house saving Fairfield’s rate payers hundreds of thousands of dollars. 


A new 1,000 Horse Power 1,200 kilowatt power generator was installed at the facility. The new generator provides backup power to all treatment process components during power outages. 


The facility upgraded its original Motor Control Centers (MCC's) to "Intelligent" MCC's. MCC's are critical electrical and power distribution infrastructure which are necessary for the operation of the treatment plant. The new "intelligent" MCC's will allow for more efficient energy management efforts at the treatment plant in addition to better data tracking and troubleshooting.


A natural gas main extension was completed for the Wastewater Plant. Staff installed natural gas house services to several buildings at the facility, eliminating the need to use propane as a fuel source. Ultraviolet Light disinfection system electrical components were upgraded to improve sustainability and optimize electric consumption. 


There are numerous projects lined up in the facility’s Capital Improvement Project Program. The employees at the plant take great pride in trying to stay a step ahead of the ever growing demands in the Wastewater Treatment Industry.