As droughts become more frequent, there is a growing need to understand how drought impacts streamflow permanence. Intermittent streams, or streams that go dry at some point during the year, are found in all ecoregions and represent over half of the global stream network length. As stream intermittence increases, there will be implications for both aquatic and terrestrial wildlife communities, land management, and water rights holders. A core challenge to understanding how drought will impact streams is the fact that hydrologic models are often better at representing periods of high flow rather than low flow. Gaining a better understanding of the processes that lead to stream drying, and how these processes are represented in models, is critical to develop tools and resources for managers who are seeking to adaptively manage aquatic ecosystems.
Focusing on the Pacific Northwest, the goals of this project are to:
- synthesize how low flows and streamflow intermittency is represented across a suite of modeling tools and identify how to use flow/no-flow observations to benchmark process-based models,
- evaluate the major uncertainties in modeling intermittent streams, and
- determine the types of decision-support tools managers need to plan for changing hydrologic regimes.
These results will ensure that models are appropriately capturing the complexity of intermittent streams, that data collected can be used to calibrate those models, and that next steps in intermittent stream research are in-line with the needs of regional partners, including tribal, state, and federal managers.
