Conjunctive Use Builds
Sustainability and Reliability
in the Sacramento Region
AS CALIFORNIA EMERGED FROM A MULTI-YEAR DROUGHT IN THE EARLY 1990s, the Sacramento region’s
water supplies and environmental resources were on an unsustainable path. Forecasts showed the area would
experience some of the fastest population growth in the state. The region was already heavily dependent upon the Lower
American River for drinking water supplies and projected to tap the river even more in the coming years. At the same
time, groundwater levels were declining steadily in some parts of Sacramento County, falling as much as 90 feet from
historic levels in the years following World War II, and contamination plumes were threatening groundwater as a viable
drinking water source.
By Rob Swartz and John Woodling
The 2014-15 drought hit the Sacramento region especially hard. Folsom Reservoir, the primary water supply source for 500,000 people,
fell to historic lows, demonstrating the vulnerability of relying on surface water. Photos courtesy of City of Sacramento.
From these times and conditions emerged the Water Forum,
an agreement among water managers, environmentalists and other
diverse stakeholders to balance the co-equal objectives of providing a
reliable and safe water supply for the Sacramento region’s long-term
growth and economic health, and preserving the fishery, wildlife,
recreational and aesthetic values of the Lower American River.
Water Forum stakeholders identified the development of a
regional conjunctive use program as critical to achieving the co-equal
objectives. With conjunctive use, water providers use more surface
water during wet years, allowing the groundwater basin to recharge,
and more groundwater during dry years, allowing more surface
water to flow down the American River for fishery and wildlife.
Decades later, the Sacramento region’s conjunctive use
program has yielded dividends even beyond those imagined at its
formation. As local water managers embark on a new era in water
reliability planning, their vision for expanding conjunctive use with
groundwater banking is emerging as key to meeting the area’s future
water supply and environmental needs while providing benefits that
extend to others statewide.
Creating the Foundation for Conjunctive Use
The Sacramento region’s conjunctive use program was made
possible through the formation of two joint powers agencies: the
Sacramento Groundwater Authority (SGA) in 1998 to equitably
and sustainably manage groundwater in the northern portion of
Sacramento County and the Regional Water Authority (RWA) in
2001 to support 21 independent water suppliers serving two million
people in working collaboratively to integrate their water systems.