RORBY Wastewater Treatment Plant, Kalundborg, Denmark

RORBY is a wastewater treatment plant located in Kalundborg, Kalundborg Kommune, Region Sjælland, Denmark. The plant is now closed and no longer in operation. It was designed with a capacity of 2100 m³/day and provided secondary treatment for the local area. As a Danish plant, it operated under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for discharges to freshwater and estuaries. The plant's coastal location would have subjected it to additional scrutiny under the directive's sensitive area provisions. The plant's discharge likely affected the coastal waters of the Great Belt region, which connects the Baltic Sea to the Kattegat. These waters support diverse marine life and are important for fisheries and migratory species.

The plant is situated near the coast of the Great Belt, a major strait connecting the Baltic Sea to the Kattegat and ultimately the North Sea. This coastal area supports diverse marine ecosystems, including fish spawning grounds and migratory bird routes. The discharge of treated wastewater into such a dynamic marine environment would have required careful management to minimize nutrient loading and protect water quality.