Tuolumne and Merced Watershed Studies
As part of the State Water Project (SWP), California piloted the CRIDA methodology as its climate change adaptation approach for two drought-prune watersheds.
Context
California’s $3.2 trillion economy relies on water but faces challenges such as flood risks, supply management, and habitat conservation, exacerbated by climate change. In response, the state’s 2020 Climate Change Adaptation Plan projected impacts like reduced water availability. To mitigate risks, California adopted the Climate Risk Informed Decision Analysis (CRIDA) approach for two watersheds.
Actions
The CRIDA implementation started with a bottom-up vulnerability assessment for the entire state. In the next phase of the State Water Project (SWP) The Merced River Basin and Tuolumne River Watershed were chosen as the pilot sites for smaller-scale, watershed-scale CRIDA analysis. The aim was to use decision scaling in the climate change vulnerability assessment of the water resources systems and adaptive planning. The stress test was done using paleo-climatic reconstructions of historic hydrology for the Merced river basin to and using an innovative stochastic weather generator for the Tuolomne River Watershed.
Outcomes
The stress test for the Merced River Basin allowed for testing of Flood-MAR implementation concept and improved the knowledge on this adaptation strategy. For the other watershed, Tuolumne, the stress test increased the understanding of the effects of atmospheric rivers connected to climate change.