In early 2016, IWR GmbH was tasked by Eigenbetrieb Stadtentwässerung Böblingen (SEBB) with the planning, tendering and supervision of the reconstruction of rainwater retention basin 302 in Böblingen. Besides the removal of the existing earth basin, a new reinforced concrete basin was planned. Furthermore, the electric and mechanic equipment is going to be renewed and supplemented.

Particular challenges in the planning process lay in the specific groundwater conditions and the pollution through explosive ordnances. Currently, the project rainwater retention basin 302 in Böblingen has entered service phase 8, i.e. construction. The floor slab and most of the walls have already been completed successfully. Construction of the basin is expected to be finalised in March.