LAWLER STL Wastewater Treatment Plant, Lawler, Iowa | Secondary Treatment Facility

LAWLER STL is a municipal wastewater treatment plant located in Lawler, Chickasaw County, Iowa, United States. The facility serves a small population of 439 residents, providing essential sanitation services to the community. As a secondary treatment plant, it meets the standard requirements for organic matter and suspended solids removal under the U.S. Clean Water Act. The plant has a designed capacity of 227.12 volume units and a current discharge volume of 151.42 volume units, indicating operational capacity below its design limit. Secondary treatment typically involves biological processes such as activated sludge or trickling filters. The plant operates under the U.S. EPA's National Pollutant Discharge Elimination System (NPDES) permit program, which sets effluent limits to protect water quality. The treated effluent from LAWLER STL is discharged into local streams that are part of the Upper Mississippi River Basin. This region supports diverse aquatic life and provides important ecosystem services. The plant's location inland, far from coastal areas, reduces direct marine impact, but its discharge contributes to the overall health of the watershed, which ultimately drains to the Gulf of Mexico.

The plant discharges into local tributaries of the Upper Mississippi River Basin, which flows into the Mississippi River and eventually the Gulf of Mexico. This watershed supports a variety of fish and wildlife species, including migratory birds and freshwater mussels. The region's agricultural landscape means that nutrient management from wastewater is important to prevent downstream eutrophication in the Gulf's hypoxic zone.