Experience with different sealing system used by the Brombachspeichersystem.

Six dams are under construction as part of the facilities for the deviation of water from the Altmuhl and Donau regime to the Regnitz Main area in the northern part of Bavaria. Depending on the various soil conditions of the Keuper geologic formation over 200,000 m2 of one phase cut off wall, two phase cut off wall (soil concrete), slurry membranes and jet grouting are installed as seals against groundwater flow. The paper describes the experience made during the sealing work. The results of a field test with a slurry membrane are discussed with special attention to the thickness of the membrane, depending on the soil, the beam and the construction method. Some suggestions are made for tendering in which the risk of the subsoil will stay with the client.