GRISWOLD WWTP - Secondary Treatment Plant in Cass County, Iowa

GRISWOLD WWTP is a municipal wastewater treatment facility located in Pleasant Township, Cass County, Iowa. The plant serves a small population of approximately 1,027 residents, reflecting its role in a rural community. As a secondary treatment plant, it provides biological treatment to reduce organic matter and suspended solids before discharge. The plant operates under the U.S. Clean Water Act, which requires National Pollutant Discharge Elimination System (NPDES) permits for all point source discharges. For small agglomerations like this, secondary treatment is the standard requirement, ensuring compliance with effluent limits that protect water quality. The plant's designed capacity of 1,313.53 units indicates it has some reserve capacity to accommodate future growth. The treated effluent from GRISWOLD WWTP is discharged into a local water body, likely a stream or river within the Missouri River basin. This discharge contributes to the overall water quality of the region, and the plant's operation helps protect downstream ecosystems and drinking water sources. The plant's inland location, far from coastal areas, reduces direct marine impact.

GRISWOLD WWTP discharges into a receiving water body within the Missouri River watershed, which ultimately flows into the Mississippi River and the Gulf of Mexico. The local watershed supports agricultural and natural habitats, and the plant's secondary treatment helps maintain water quality standards. Downstream ecosystems benefit from reduced nutrient loads, which is critical for preventing eutrophication in the Gulf of Mexico's hypoxic zone.