Cosumnes River. Source: Kayaking CA Delta
The Cosumnes watershed is one of the last major undamned river systems in the east side of the Central Valley. The State of California has identified it as a critical watershed for the many special status and culturally important species, ranging from Chinook salmon to Sandhill cranes. The bottom of the watershed includes the Sacramento-San Joaquin Delta, and divides the Sacramento Valley and the San Joaquin Valleys. In this tidally-influenced area, there is the federal Stone Lakes National Wildlife Refuge, and the Cosumnes River Preserve, which includes the Bureau of Land Management, Department of Water Resources, The Nature Conservancy and many other conservation land managers and their holdings. Within this area, the Sacramento Regional County Sanitation District (Regional San), Sacramento region’s wastewater conveyance and treatment agency has developed a tertiary-treated recycled water program that can provide up to 50,000 acre feet of year for in lieu groundwater substitution for farms to reverse a cone of depression. In the middle Cosumnes watershed, there are numerous opportunities on working lands to recharge surface water and improve agricultural water use efficiency. Pilot programs have begun to use surface water from the Folsom South Canal to recharge the aquifer. In the upper watershed, preliminary conversations have begun to assess the opportunities to increase forest resilience, reduce the risk of interface fires, and improve watershed health. Severe drought has begun in the State of California and the impacts have brought an increased spotlight to water recycling, conjunctive use, watershed fire risk reduction, and the benefits the integration of these benefits can provide. More than ever, the Sacramento region and the entire State of California need to increase use of recycled water and investigate and implement new sustainable water supply projects.
CWAC members have an exceptional opportunity to proactively restore and manage groundwater, while improving stream flows in the lower Cosumnes River, enhancing riparian habitats and wetlands, sustaining prime agricultural lands, and improving regional water supply reliability.
The Freshwater Trust and Regional San, in collaboration with regional stakeholders, including the Nature Conservancy and Ducks Unlimited who are already supporting local programs, are engaged in elements of the Harvest Water program. We see an opportunity to offer multiple benefits including replenishment in a critical watershed, multiple paths to support Bay area drinking water supplies, habitat protection efforts, and near-term benefits to the Sacramento-San Joaquin Delta.
Project lead: The Freshwater Trust
Participating CWAC members: In the Stone Lakes NWR and the Cosumnes River Preserve | The Nature Conservancy and Ducks Unlimited
Additional partners: Wanted!
To learn more: Contact Erik Ringelberg, California Director, The Freshwater Trust – [erik@thefreshwatertrust.org]