The dam wall is constructed from quarry stone masonry bonded with mortar, typical of the industrial-era reservoir designs in the Sauerland region.
The reservoir serves as part of the regional drinking water supply managed by the local utility company, AVU.
During construction, a temporary narrow-gauge railway was utilized to transport building materials to the site.
The dam's basin covers an area of roughly 13 hectares at full capacity.
The project was initiated specifically to support the growing steam-powered industrial demands of the local steel and textile factories in the 19th century.
The Haspertalsperre is a gravity dam constructed between 1901 and 1904 to provide drinking water and flood protection for the Haspe district of Hagen. The structure consists of a curved masonry wall reaching a height of 35 meters and a crest length of 245 meters. Its reservoir, fed by the Hasper Bach, holds approximately 2.3 million cubic meters of water. A paved circuit path surrounds the reservoir, offering a continuous loop for pedestrians. The site serves as a local recreational area integrated into the wooded hills of the Ennepe-Ruhr district. The masonry remains largely in its original historical configuration, reflecting early 20th-century hydraulic engineering standards.
The center of the dam crest provides the best vantage point looking down into the valley and across the reservoir basin.
Wear sturdy walking shoes as the surrounding forest paths can be uneven and muddy after rainfall.
Carry your own water and snacks, as there are no commercial vendors directly on the reservoir banks.
Check local weather reports specifically for the Hagen hills, as they often experience higher precipitation than the city center.
Do not attempt to swim or enter the water, as it is a protected drinking water reservoir with strict prohibition of contact.
Stick to designated marked paths to protect the water quality and local wildlife habitats; cycling is often restricted on specific narrow sections.
