Publication Date
4-8-2008
Abstract
The Connecticut Department of Environmental Protection (CTDEP) is in the process of revising minimum streamflow regulations pursuant to Public Act 05-142. One important aspect of streamflow regulations development in Connecticut pertains to the assigning a streamflow class to each perennial river and stream in the state. To accomplish this goal, CTDEP has proposed using the Hydrologic Stressor Index (HSI), an index comprised of four metrics -impervious cover, diversions, dams and return flow. These four metrics were chosen because of their potential to modify natural streamflow and because statewide data layers were available to calculate the metrics for these four parameters. After calculating initial HSI scores, the streamflow class may be modified using a list of additional factors that indicate the existing or future streamflow condition. These additional factors will be outlined in the streamflow regulations and will be used to modify the HSI to develop a preliminary streamflow class map for public comment. One such "additional factor" being considered is density of a native fluvial specialist fish species, the brook trout (Salvelinus fontinalis). This presentation will explain how these "additional factors" can be used to modify initial HSI scores to develop streamflow class maps for public comment using brook trout as an example.