The Sacramento-San Joaquin
The Sacramento and San Joaquin River basins extend nearly 500 miles north to south in what resembles a delicate array of arteries. The network acts like a major organ in the body of California. Trillions of gallons of freshwater move through it and are delivered to the rest of the state. Underneath, stores of groundwater continue their rise and fall, influenced by human usage and long-term climate effects.
The diagnosis on the health of these basins is disquieting. Drinking water wells running dry, winter snowpack disappearing, catastrophic flood risk imperiling water infrastructure, and Delta fish populations plummeting towards extinction. Additionally, the stressed basins are struggling to provide critical irrigation water for seven of the top 10 agricultural counties in the nationʼs leading farm state. Pretty soon, the system will need life support.
“The ongoing depletion of the groundwater actually disconnects rivers and streams from their flows,” said Ben Wallace, Senior Conservation Project Manager. “The looming challenges are invisible, until the rivers disappear, abruptly drying up.”
In 2021, TFTʼs California team continued its work to protect this vital resource. Notably, a new groundwater replenishment program was established in the Cosumnes. A major water district with excess surface water during the winter will apply it to dormant agricultural fields and sell credits to TFT in support of Microsoft and Amazon Web Servicesʼ “net zero” water sustainability goals.

A flock of greater white-fronted geese congregate at the Sacramento National Wildlife Refuge in Willows, Calif. Florence Low / California Department of Water Resources
“We are helping set California on the path to sound implementation of its landmark Sustainable Groundwater Management Act,” said Wallace. “We have to keep gathering diverse interest groups around the same table.”
Other projects continued. Aquifer recharge projects were adopted into a Groundwater Sustainability Plan in the Northern Delta, in both the South American and Solano subbasins. Work with Sacramento Regional County Sanitation District took steps forward to providing local farmers a safe and reliable water supply while also replenishing groundwater resources. First, letters of intent were signed with more than 50 landowners to receive recycled water delivery in late 2024. Second, the EcoPlan began implementation planning and priority analysis in 2021.
“The EcoPlan provides a critical opportunity to support biological diversity in the region for generations to come, while building capacity for sustainable agriculture,” said Wallace.
After the years of careful planning and coordination, what are the expected outcomes? Turning invisible impacts into visible solutions, such as sustainable irrigation for farmers using recycled water rather than pumping a dwindling supply of groundwater; protected drinking water for domestic wells in underserved communities; preserved natural habitat for wildlife and fish; and a regional groundwater supply in balance with multiple uses.