Stream geomorphology data being collected to aid watershed managers in setting flow targets

SCCWRP and its partners have begun field sampling at coastal stream sites across California to collect data on geomorphic structure, part of an ongoing effort to develop a standardized framework to help watershed managers set environmental flows that protect stream health statewide.

Researchers in July began collecting data on stream geomorphology – or the physical characteristics of a stream channel – to better understand how geomorphic structure influences a stream’s hydrologic flow patterns and overall ecological functioning. Researchers plan to place California coastal streams into categories based on their geomorphic characteristics, then build a tool that can provide channel morphology information for stream sites across coastal California.

Watershed managers will be able to use the geomorphology information to improve resolution and streamline and standardize the process by which they evaluate environmental flow needs for stream sites; these analyses are the foundation for setting scientifically defensible flow targets.

The geomorphology classification project is the next step in the ongoing development of the California Environmental Flows Framework, a best-practices approach for establishing ecologically relevant flow targets for streams based on flow patterns, channel morphology and the response of the ecosystem. Researchers already have classified streams across California into nine major categories based on their hydrologic characteristics.