In addition to identifying climate vulnerabilities, the plan outlines 19 watershed adaptation strategies and 119 potential adaptation actions focused on reducing long-term risks associated with drought, flooding, wildfire and extreme heat. Photo courtesy of Magnific

SACRAMENTO REGION, CA (MPG) - The Regional Water Authority (RWA) and regional partners have completed the American, Bear and Cosumnes Watersheds Resilience Plan, a new climate resilience strategy that evaluates how climate change is expected to affect water supplies, flood risk, ecosystems, infrastructure and communities across one of California’s most important watershed systems.

Funded by the California Department of Water Resources through the State’s Watershed Resilience Pilot Program, the Sacramento region was selected as one of five pilot regions statewide to help develop watershed-scale climate resilience planning approaches that could inform future implementation efforts across California.

The plan examines the interconnected American, Bear and Cosumnes river watersheds, which support more than two million people, provide approximately eight percent of California’s developed water supply and contribute important flows to the Sacramento-San Joaquin Delta.

The plan combines climate modeling, vulnerability analysis, equity assessment and stakeholder engagement to evaluate how climate change could reshape the region over the coming decades and identify actions that can help communities and ecosystems adapt.

Key findings for the Sacramento region include critical snowpack that feeds these watersheds could decline by approximately 60% by mid-century. Snowmelt is projected to occur two to four weeks earlier. Extreme heat days over 95 degrees could increase by roughly 20 days annually. Wildfires are projected to become 17% more frequent. Extreme precipitation events could become 15% more intense. Peak flood flows could increase by approximately 19%.

 Mid-Century Median Projected Conditions chart. Photo courtesy of Regional Water Authority (RWA)

The plan also finds that climate impacts will not be experienced equally. Lower-income communities, Tribal communities and outdoor workers may face greater exposure to extreme heat, flooding, wildfire smoke and economic disruption.

“The science is clear that climate change is already reshaping our watersheds,” said Jim Peifer, executive director of the Regional Water Authority. “The question is no longer whether these impacts are coming, but how quickly the region can act to prepare. This plan gives the Sacramento region a shared framework to move from vulnerability assessment to implementation — and positions regional partners to move quickly as funding and project opportunities emerge.”

In addition to identifying climate vulnerabilities, the plan outlines 19 watershed adaptation strategies and 119 potential adaptation actions focused on reducing long-term risks associated with drought, flooding, wildfire and extreme heat.

The plan also establishes a decision-making framework intended to help agencies and partners evaluate and prioritize future resilience investments based on factors such as regional benefit, climate risk reduction, ecosystem improvements, equity considerations and implementation readiness.

Strategies identified in the plan include reducing wildfire risk and improving forest health in the Sierra headwaters, strengthening flood protection for vulnerable communities, expanding groundwater recharge, protecting cold-water habitat for salmon and other native fish species, expanding flood forecasting and early warning systems, and advancing regional projects that provide multiple water supply, ecosystem and community resilience benefits.

“For more than two decades, DWR has encouraged Californians to connect across watersheds,” said Karla Nemeth, director of the California Department of Water Resources. “A warmer climate stresses resources from forests to aquifers. That makes the hard work of collaboration more important than ever. DWR’s $2 million grant to the Regional Water Authority yielded a plan that tells a powerful story about future risks and marks a clear path to resilience. This plan positions the people of the American, Bear, and Cosumnes watersheds to cope with a changed climate. It is an early example of the kind of work needed across the state, and it helps build DWR’s momentum to update the California Water Plan to deliver more precise, localized and action-oriented water supply strategies.”

The planning effort was led by the Regional Water Authority with support from Jacobs, Valley Vision, Khadam Consulting, the Water Forum, regional water agencies, local governments, Tribal representatives, community organizations and Watershed Network participants.

“The region already has many of the partnerships, technical tools and local initiatives needed to strengthen resilience,” Peifer said. “This plan helps align those efforts and creates a clearer path forward for coordinated regional action.”

The full American, Bear, and Cosumnes Watersheds Resilience Plan is available at: https://rwawatershedsresilience.com/plan/