Vincennes Wastewater

The City of Vincennes owns and operates a Class IV activated sludge wastewater treatment facility that provides preliminary, primary and secondary treatment for influent wastewater. The wastewater treatment facility treats domestic, commercial and industrial wastewater prior to discharge to the Wabash River in Knox County, Indiana.

Since its original installation in 1912, several improvement projects have been completed on the treatment plant. The original facility consisted of only one pump station and bar rack for preliminary screening before discharge to the river.  In 1958, a new pump station and primary treatment facilities were constructed that had a design flow of 4.56 million gallons per day (MGD).

The facilities included comminution, grit removal, primary settling, chlorine disinfection, and anaerobic sludge digestion. The facility was then again updated in 1973 with the addition of secondary biological treatment, including aeration and clarification. Other facility improvements and equipment replacement were conducted in 1995.  Despite these improvements, the wastewater treatment capacity did not increase beyond the original 4.56 MGD.

To address the City’s improvement and expansion needs, as well as regulatory concerns, a plan for the expansion and upgrade of the Vincennes Wastewater Treatment Facility began development in around 2000. The expansion and upgrade, which was completed in 2004, increased treatment capacity to an average daily design flow of 7.5 MGD. That is an increase of approximately 63% over the 4.56 MGD flow design the City had since 1958.  The design peak hourly flow increased from 5.65 MGD to 22 MGD to full treat all wet weather flow at the facility.

Some other improvements that were deemed a necessary part of the upgrade were collection system improvements. The collection system is the actual network of sewer pipes, manholes, lift stations and pump stations that direct the wastewater flow to the treatment facility. These improvements included new sanitary interceptors and existing interceptor improvements to collect wastewater from currently unsewered areas and to convey wastewater to a new lift station. The new, larger lift station at Watson Street pumps wastewater through a force main directly to the plant head-works. A drainage project in the 13th and St. Clair area also was completed which helped to alleviate some of the flooding those residents experienced in wet weather.

The facilities included comminution, grit removal, primary settling, chlorine disinfection, and anaerobic sludge digestion. The facility was then again updated in 1973 with the addition of secondary biological treatment, including aeration and clarification. Other facility improvements and equipment replacement were conducted in 1995.  Despite these improvements, the wastewater treatment capacity did not increase beyond the original 4.56 MGD.

There are 18 employees at the Vincennes Wastewater Treatment Facility.  The facility has a laboratory that conducts daily testing of influent and effluent water quality through various processes. Three full-time operators maintain the processes in the plant and sludge production. The collection system crews are the employees that you see in the streets every day. They are responsible for sanitary maintenance, tap replacements and installations, storm inlet cleaning and maintenance, storm line cleaning and maintenance, lift station maintenance and any other wastewater conveyance issues that may arise.