CALMAR WWTP - Calmar, Iowa Wastewater Treatment Plant

CALMAR WWTP is a municipal wastewater treatment facility located in Calmar, Iowa, a small community in Winneshiek County. The plant serves a population of approximately 978 residents, reflecting its role as a small-scale treatment facility in the rural Midwest. As a secondary treatment plant, CALMAR WWTP provides biological treatment to remove organic matter and suspended solids, meeting the standard requirements under the US Clean Water Act. The plant has a designed capacity of 908.50 (likely in thousand gallons per day or similar unit) and currently handles a discharge volume of 389.90, indicating operational capacity below design levels. For small communities like Calmar, secondary treatment is typical and sufficient to protect local water quality. The treated effluent from CALMAR WWTP is discharged into a receiving water body that ultimately drains into the Upper Mississippi River basin. This region is part of the Driftless Area, known for its spring-fed streams and diverse aquatic ecosystems. The plant's discharge contributes to the overall water quality in the local watershed, which supports recreational uses and wildlife habitat.

CALMAR WWTP discharges into a local stream that flows into the Upper Iowa River, a tributary of the Mississippi River. The Upper Iowa River is a designated scenic river with high ecological value, supporting species such as smallmouth bass and freshwater mussels. The plant's secondary treatment helps maintain water quality in this sensitive watershed, which is part of the larger Mississippi River system that drains into the Gulf of Mexico.