Stormwater Management at Langer See

Aerial view, © Zweckverband Flugfeld Böblingen/Sindelfingen, Friedrich Stampe

The site of the former Böblingen/Sindelfingen Airfield is being developed into a high-quality urban quarter. The central element of the urban design is the “Langer See” (Long lake), which also serves as a means of stormwater management.

Retention basins normally control precipitation runoff. On the airfield, however, we are breaking new ground: Langer See is not only a central element of the urban design, but above all the very heart of the airfield’s stormwater management system. Apart from a few exceptions, all roofs, yards, traffic areas, and green spaces feed the precipitation into the lake via a so-called separated system, thus keeping it segregated from the wastewater. En route to the lake, the rainwater passes through soil filters, which clean it and ensure optimal water quality. During times of abundant rain, the lake acts as an intermediate reservoir for precipitation and – in the heavily strained upper reaches of the Schwippe river – assumes the task of stormwater retention and thus flood protection. Before the rainwater flows into the lake, it passes through one of three stormwater treatment ponds distributed at different points along the lake.

Key Elements of Stormwater Management

Retention soil filters with stormwater sedimentation ponds and secondary phosphorus elimination, connection to the Langer See (flood discharge and filtrate outlet)
Artificial lake with bottom seal, retaining structures, reed zone, and lake overflow as well as technical system for quality control
Connection of the overflow to existing surface waters