FH WETLAND SYSTEMS Ltd.

The species of insects that live in rivers and streams vary depending on the purity of the water. Pristine water has a wide variety of species in an even balance of predators and prey. These require high levels of oxygen and low nutrient levels. They are often found at riffle areas in a river; the swiftest flowing water. Their bodies are streamlined and adapted to gripping tightly to the stones. Medium quality water has less of a variety of species but the population of individual species may be greater. These insects tolerate lower oxygen levels in the water. Very poor water quality encourages only a few species, but these may be present in very high numbers. By checking the insect life in a river, we can check the quality of the water.

The EPA Q-ratings on streams and rivers is based upon biological monitoring, and is sometimes needed for planning or licincing. FHWS can carry out Biological Monitoring on your stream or river to assess the water quality and advise on methods for improving water quality and encouraging fish and other aquatic life.

Biological monitoring