Weir Großhesselohe

The Challenge

Stadtwerke München (SWM) operates the Großhesselohe weir facility on the Isar River, originally constructed in the 1920s. To ensure continued flood protection and water regulation, a complete replacement of the aging weir system was required. The project also aimed to restore ecological continuity at the site, aligning with modern environmental standards and improving the river’s natural dynamics within the urban landscape of southern Munich.

The Solution

Tractebel supported the planning and design of a new weir system featuring three modern weir fields and an integrated fish ladder to facilitate aquatic migration. The project also included the construction of a separating weir between the Isar and the works canal, ensuring effective water management and ecological balance. The design was tailored to enhance operational safety and environmental performance, incorporating advanced weir flap systems with torsion and air-operated drives.

The Impact

The redesigned weir significantly strengthens the flood protection capabilities of the facility. By reducing the number of weir fields and designing center pillars to be overflowed during major floods, the system ensures greater resilience. The new flap mechanisms improve operational reliability and support the required minimum water release, contributing to ecological sustainability. This project exemplifies Tractebel’s expertise in combining hydraulic engineering with environmental stewardship.