The determination of stream quality is based on the percent of imperviousness coverage. The categories indicate a qualitative degree of stream deterioration due to urbanization, as measured by the imperviousness coverage. Streams are rich in biodiversity. Good Water quality.
Water quality is fair and biodiversity if fair.
Water quality is fair-poor and stream biodiversity is low. Schueler, T. 1994 . The importance of imperviousness. Watershed Protection Techniques. The content of this document contains information compiled and synthetized by Todd Doley and Jose Lopez-Collado.