CARBON WWTP, Calcutta, Indiana | Secondary Wastewater Treatment Plant

CARBON WWTP is a municipal wastewater treatment facility located in Calcutta, Clay County, Indiana. Serving a small population of around 350 residents, the plant provides secondary treatment to ensure effluent quality meets state and federal standards. The plant operates under the U.S. Clean Water Act, which requires secondary treatment for municipal wastewater. With a designed capacity of 94.64 million gallons per year, the facility manages local wastewater from the Calcutta area. As a small agglomeration, it is subject to EPA NPDES permitting through the Indiana Department of Environmental Management. The treated effluent is discharged into nearby streams that flow into the Wabash River basin, ultimately reaching the Ohio River and Mississippi River system. The plant plays a key role in protecting local water quality and downstream ecosystems in the Wabash River watershed.

The plant discharges into local tributaries of the Wabash River, which flows southwest to the Ohio River and then to the Mississippi River. The Wabash River supports diverse aquatic life and is an important ecological corridor in the Midwest. Secondary treatment reduces organic pollutants and suspended solids, helping maintain water quality in this agriculturally influenced region.