Kaltental Wastewater Treatment Plant, Blonhofen, Bavaria

Kaltental wastewater treatment plant is located in Blonhofen, a district of Kaltental in the Ostallgäu district of Bavaria, Germany. The plant serves a population of approximately 2,230 people, classifying it as a small agglomeration under the EU Urban Waste Water Treatment Directive (UWWTD). The plant provides secondary treatment, which is the minimum required by the EU UWWTD for freshwater discharges from agglomerations of this size. With a designed capacity of 2,500 m³/day and an average discharge volume of 564.36 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into the local watershed, which ultimately drains into the Danube River basin via the Wertach and Lech rivers. The region is characterized by its proximity to the Alps and the Allgäu region, known for its sensitive aquatic ecosystems and groundwater resources.

The plant's discharge enters the local stream network that flows into the Wertach River, a tributary of the Lech River, which joins the Danube near Donauwörth. The Danube then flows into the Black Sea. The watershed supports diverse aquatic life, including fish species such as grayling and brown trout, and is part of a region with important groundwater recharge areas. The secondary treatment helps protect downstream water quality in this ecologically sensitive Alpine foothill region.