Post-industrial river water quality-Fit for bathing again?

Area of Science:

• Environmental Science
• Microbiology
• Water Quality Management

Background:

• The Ruhr River has a long-standing bathing ban due to historical water quality issues.
• Increasing demand for recreation, including bathing, highlights the need to reassess the ban.
• Microbiological water quality remains the primary concern for recreational restrictions.

Purpose of the Study:

• To investigate the feasibility of lifting the bathing ban on the Ruhr River.
• To analyze microbiological water quality, including faecal indicator organisms (FIOs) and pathogens.
• To evaluate current freshwater quality criteria and their limitations.

Main Methods:

• Reviewed microbial contamination sources (sewage, overflows, runoff).
• Assessed relationships between FIOs and pathogens in recreational waters.
• Critically evaluated the representativeness of FIOs in water quality standards.
• Outlined the 'Safe Ruhr' project's working program.

Main Results:

• Contamination sources can be managed through technical interventions.
• Water quality is transient, with occasional exceedances of legal limits.
• A flexible bathing site management system is proposed as an innovative solution.
• A situation-adapted system for lifting the bathing ban appears realistic.

Conclusions:

• Lifting the bathing ban on the Ruhr River is achievable.
• Technical solutions for contamination exist, but political decisions are crucial.
• Flexible management and real-time warnings can enhance bathing safety.
• An adapted system can facilitate the legalization of Ruhr River bathing.