Jump to main content or area navigation.

Contact Us

CADDIS Volume 2: Sources, Stressors & Responses

energy sources physical habitat hydrology temperature water and sediment quality stormwater runoff wastewater inputs riparian and channel alteration urbanization

Imperviousness & biotic condition

Total or effective impervious cover has been linked to numerous changes in stream biotic assemblages. These changes include (but are not limited to):


Click below for more information on specific topics

effective vs. total imperviousness button imperviousness and biotic condition button thresholds of imperviousness button
Figure 18. Occurrence probability of four fish species vs. impervious cover. Black line represents response curve based on mean parameter estimate for effective impervious area (EIA); gray lines represent response curves based on 5% and 95% values for parameter estimate for EIA. For three of the four species (all but speckled madtom), occurrence probability was predicted to approach zero at approximately 2-4% effective impervious cover.
From Wenger SJ et al. 2008. Stream fish occurrence in response to impervious cover, historic land use, and hydrogeomorphic factors. Canadian Journal of Fisheries and Aquatic Sciences 65:1250-1264. © 2008 NRC Canada or its licensors. Reproduced with permission.
Photos courtesy of Noel Burkhead, USGS.

Jump to main content.