Cost-efficiency aspects for fish passage restoration in the Ruhr River Basin.

Area of Science:

• Environmental Science
• River Basin Management
• Aquatic Ecology

Background:

• The European Water Framework Directive mandates sustainable aquatic ecosystem management.
• Anthropogenic modifications in the Ruhr River Basin have resulted in approximately 1300 weirs, many impeding fish passage.
• Restoring ecological status requires addressing barriers to free fish movement.

Purpose of the Study:

• To develop a holistic strategy for restoring fish passage in the Ruhr River catchment.
• To integrate scientific, technical, and economic considerations into fish passage restoration.
• To establish a fair and efficient financing model for implementing necessary measures.

Main Methods:

• Assessing the passability of existing weirs.
• Identifying potential (spawning) habitats for fish.
• Developing and evaluating fish passage structures.
• Conducting cost-benefit analyses for site-specific and catchment-wide designs.
• Evaluating economic benefits across various sectors.

Main Results:

• The majority of the 1300 weirs in the Ruhr River Basin are impassable or have restricted fish passage.
• A holistic approach was developed by the Ruhrverband to address fish passage restoration.
• Cost-benefit analyses and economic benefit evaluations were integral to the strategy.

Conclusions:

• A comprehensive strategy integrating ecological and economic factors is crucial for effective fish passage restoration.
• A collaborative financing model involving all beneficiaries ensures fair cost distribution and efficient implementation.
• Restoring fish passage is vital for achieving the ecological objectives of the European Water Framework Directive in the Ruhr River Basin.