Wastewater Treatment Plant

Early Sewers

The first sewers were constructed in the 1930s and early 1940s by the WPA program with the original plant constructed of simple settling tanks and sand filters which were located just west of Prairie Run (approximately 500 feet. south of what is now Granville Street). 

Mid-Century Upgrades

In 1967, a new plant was built at the east end of Middleview Drive and upgraded in 1987, the mid 1990s and 2004. Those upgrades brought our current location to a maximum design flow of 4 million gallons per day rated and permitted at 1.125 million gallons per day class 3 facility. 

Current Facilities

The system and plant currently have 40+miles of main lines with 17 pumps in operation daily. Some of the features at the activated sludge plant include a grit removal system, oxidation ditches, digesters, clarifiers, belt press, and ultra-violet disinfection system.

With Sunbury's rapid growth rate, the collection system and treatment plant are constantly maintained and prepared for the future

Waste Water Treatment Expansion 


The WWTP is being expanded from 1.125 MGD (million gallons per day) to 2.0 MGD.  Construction is underway by Simonson Construction Services and will continue through December 2027. The map (attached/link) depicts proposed timing for the construction/upgrade of various areas and components at the WWTP.  There are no planned outages in service during construction. 

The City of Sunbury owns and operates the Wastewater Treatment Plant (WWTP) under NPDES Permit No. 4PB00010*ID. This permit has an effective date of August 1, 2019 and an expiration date of July 31, 2024. The Sunbury WWTP was commissioned in 1967 and was upgraded in 1985 and 2004. The current WWTP consists of influent pumping, screening, grit removal, oxidation ditches, final clarifiers, UV disinfection, post aeration, sludge dewatering on the belt filter press and sludge drying/storage beds. The final effluent is discharged to Prairie Run, a tributary to Big Walnut Creek. The current permitted design flow for the WWTP is 1.125 million gallons per day (MGD).

Click Here for a map and schedule of the WWTP.