SEI worked with the California State Water Resources Control Board to develop SacWAM, a hydrologic and system operations model that recreates the Sacramento River Basin and Sacramento – San Joaquin Delta. The model — created using WEAP — not only shows how this complex water system currently operates; it also shows the Delta’s unimpaired state, or how its water would flow if there were no dams, diversions or infrastructure.

Aerial view of farmland, both cultivated and fallow, and river channels in the Sacramento-San Joaquin River Delta. Photo: Bill & Brigitte Clough / Getty Images

The State Water Resources Control Board is using SacWAM to assess potential revisions to regulations of the water system, weighing the trade-offs as it aims to strike the right balance between protection of ecosystems and water for Californians and agriculture. The model allows the Board to estimate the flow of the River under a range of regulatory options, and to see the effects of those various options on agriculture, water supply and fisheries, among other things.

The Delta is one of the largest estuaries in the United States, and serves as a habitat for hundreds of species of wildlife. It is also the hub of California’s water system, providing water to 25 million people and 3 million acres of farmland.