IRWIN WASTE STAB PONDS - Secondary Wastewater Treatment in Shelby County, Iowa

IRWIN WASTE STAB PONDS is a wastewater treatment facility located in Douglas Township, Shelby County, Iowa, United States. The plant serves a small population of 341 residents, reflecting its role in a rural community. As a secondary treatment plant, it provides biological treatment to reduce organic pollutants and suspended solids before discharge. The plant operates under the U.S. Clean Water Act, which requires secondary treatment for municipal wastewater. With a designed capacity of 246.05 units and an average discharge volume of 151.42 units, the facility operates below its capacity, indicating room for future growth. The treatment process involves stabilization ponds, a common method for small communities due to low energy and maintenance requirements. The treated effluent is discharged into local waterways that drain into the Missouri River basin, ultimately reaching the Mississippi River and the Gulf of Mexico. The plant's location in the Midwestern United States means it plays a role in protecting downstream water quality in a region dominated by agriculture, where nutrient pollution is a key concern.

The plant discharges into tributaries of the Missouri River, which flows into the Mississippi River and then the Gulf of Mexico. This watershed is part of the larger Mississippi River Basin, which is ecologically significant for its biodiversity and as a migratory corridor for birds and fish. The region's agricultural runoff contributes to nutrient loading, making the plant's secondary treatment important for reducing local organic and nutrient pollution.