Streamflow Alteration

A full range of natural flows is needed to maintain the ecological processes of a stream system. One important example is pulses of high flows during spawning season. Variation in flow helps to create and maintain the range of habitats needed for diverse, healthy aquatic communities and ecosystems. This indicator compares the annual variations in flow (hydrographs) for the rivers against the major components of a flow regime at a relatively unaltered river in the same region (Squannacook River). It compares the magnitude, frequency, duration, timing, and rate of change of flows.