Shifting to Groundwater During Drought
The Sacramento region has been moving toward more conjunctive use of surface water and groundwater depending on hydrologic conditions, as demonstrated in the chart below. Conjunctive use is the coordinated use of surface water during wet years and groundwater during dry years.
This trend is not as evident between 2000 and 2010 when, for example, significantly more surface water was used in 2008 even though it was classified as a drier year. In 2010, however, additional Water Forum requirements related to surface water use came into effect. Since that time, conjunctive use has increased. For example, 2010, 2011 and 2012, which classified as wet or average, used more surface water than groundwater. The three latest dry years, 2013, 2014, and 2015 all saw more groundwater used than surface water.
In addition, the region’s overall water use has decreased during the past decade, which is related to increases in water use efficiency. The additional conservation measures in response to drought conditions in 2014 and 2015 are also evident. The region conserved approximately 20 percent in 2014 and 30 percent in 2015 compared to 2013.