Detailed view for Lechbruck

Concerned RiverLech
TypeInflatable, water filled
Short Description

Lechbruck weir is located on the Lech River, in Germany, and was completed in 2001.

It is a water-filled inflatable dam and it is composed of 3 spans of 47 meters wide and 1.25 meters high and one span of 28 meters wide and 3.35 meters high, for a total length of 169 meters.

Main characteristics
Water Head (m)Unknown
Upstream height (m)730.27
Downstream height (m)Unknown
Discharge (m/s)71.6 - 971
Total length (m)169
Number of spans & dimensions

4 spans :

  • 3 spans of 47 m
  • 1 span of 28 m
Weir height (m)1.25
Progress statusCompleted
Date of completion10/15/2001

Allgäuer Überlandwerk GmbH (AÜW)


Allgäuer Überlandwerk GmbH (AÜW)

Design group

RMD-Consult GmbH, Munich, Germany 

  • Hydroconstruct Company Ltd., Enterprise for Water and Energy Techniques, Austria (planning).
  • Ceska gumarenska spolecnost, a.s., Czech Republic (rubber membrane).
  • Josef Hebel, Germany (civil engineering)
Cost estimationN/A


PIANC References for this project

In Progress


The dam is located in the Alps, at the border between Germany and Austria and was built for hydro-power purpose. It is a water-filled inflatable dam. About 20 km upstream is an artificial lake which represent a huge amount of hydro-electricity.

This dam was built in 2000 and 2001 in replacement of an old timber one. A part of the new dam is on the old base plate while the rest is directly built on rocks.

The goal of the dam is to maintain a constant upstream level. As the hydropower capacity is reached, the membrane is deflated in order to keep the concession level constant. With this procedure, the membrane is fully inflated about 200-220 days/year.

Breakers are attached to the membrane to damp the vibration.

Some good points for inflatable dams are a low operation cost and a good behaviour with sediments because they can flow over the membrane.

It can also be noted that, for the design, it was considered that, at any time, none of the spans could be bloked by the membrane. For any other kind of dam, the codes require to consider a bloked span.

The choice between air-filled and water-filled was decided because of the fact that the dam is not perpendicular to the flow. An air-filed membrane would have caused more oscillations.

Documents to download
  • 104- PReview WG166- Lechbruck.pdf - 104- PReview WG166- Lechbruck.pdf