DIAMOND STP - Advanced Wastewater Treatment Plant in Diamond, Illinois

DIAMOND STP is an advanced wastewater treatment facility located in Diamond, Grundy County, Illinois, United States. The plant serves a population of approximately 2,557 residents, providing essential sanitation services to this small community in the Midwest. As an advanced treatment plant, DIAMOND STP goes beyond secondary treatment standards, likely incorporating nutrient removal or other tertiary processes. With a designed capacity of 2,460.51 million gallons and an actual discharge volume of 522.39 million gallons, the plant operates well below its capacity, indicating room for future growth. Under the U.S. Clean Water Act, such facilities are regulated through National Pollutant Discharge Elimination System (NPDES) permits issued by the Illinois Environmental Protection Agency. The plant's treated effluent is discharged into local waterways that ultimately drain into the Illinois River basin, a major tributary of the Mississippi River. This connection to the Mississippi River system means the plant's operations affect downstream ecosystems, including the Gulf of Mexico, where nutrient pollution contributes to seasonal hypoxic zones. Advanced treatment at this facility helps mitigate such impacts.

DIAMOND STP discharges into the Illinois River watershed, which flows into the Mississippi River and eventually the Gulf of Mexico. The plant's advanced treatment reduces nutrient loads that could otherwise contribute to algal blooms and hypoxic conditions in the Gulf. The local area features a mix of agricultural and residential land use, making effective wastewater treatment critical for protecting both local streams and downstream aquatic habitats.