KA Hodenhagen - Advanced Wastewater Treatment Plant in Riethagen, Lower Saxony

KA Hodenhagen is an advanced wastewater treatment plant located in Riethagen, a locality within Hodenhagen in the district of Heidekreis, Lower Saxony, Germany. The plant serves a population equivalent of approximately 5,680 people and has a designed capacity of 10,000 cubic meters per day, with an average discharge volume of 910.75 cubic meters per day. As an advanced treatment facility, KA Hodenhagen goes beyond secondary treatment to remove nutrients such as nitrogen and phosphorus, which is typical for plants in sensitive catchment areas under the EU Urban Waste Water Treatment Directive (91/271/EEC). The directive requires tertiary treatment for agglomerations above 10,000 PE discharging into sensitive areas, but smaller plants like this one may also adopt advanced treatment to meet local water quality standards. The plant's treated effluent is discharged into the local water system, which ultimately drains into the Aller River, a tributary of the Weser. The Weser flows into the North Sea, making the plant part of the Weser basin. The advanced treatment helps protect downstream aquatic ecosystems, including the Aller's floodplain habitats and the Weser estuary, from nutrient pollution.

The plant discharges into the Aller River, which flows into the Weser and then the North Sea. The Aller is a lowland river with extensive floodplains that support diverse aquatic life and migratory fish. Advanced treatment at KA Hodenhagen reduces nutrient loads, helping to prevent eutrophication in the downstream Weser estuary and North Sea coastal waters.