Eco-engineering for clarity. Clearing blue-green ponds and lakes in an urbanized area

Summary

Many urban ponds and lakes suffer from toxic cyanobacterial blooms. This causes health risks for citizens, pets and other animals, and often results in malodor, scums and turbid water without submerged vegetation. Curative approaches are often only effective in the short-term, if effective at all. Research showed that freshwater mussels can be effective in clearing turbid urban waters. The sustainable approach addresses nutrient reduction, with focus on phosphorus, often including fish biomass control and reconstruction of the water body. Phosphorus control targets the reduction of the external loading and the internal pool of potentially bioavailable phosphorus. The approach was effectively applied in four study lakes, and the efficacy of various techniques to reduce the pool of potentially bioavailable phosphorus was compared. Chemical phosphorus binding can be an attractive alternative for traditional and expensive dredging.