The hike in usage roughly correlates to decreased rainfall the past few winters, data provided by the research and policy organization shows.
“There's some good news in this report, but overall it shows just about everyone needs to (do) a better job conserving water," said Ray Ellis, Equinox Center board chairman. “Perhaps just as important is the need for clear and consistent messaging from all of our water districts and government agencies."
In Fiscal Year 2011, a year in which nearly 13 inches of rain fell, the average resident used just over 30,000 gallons. The total went up to nearly 31,000 gallons, 32,000 gallons and about 33,500 gallons in subsequent years, according to the study.
The time period for the study was on the heels of a previous drought in which San Diegans cut back on consumption.
The Equinox Center based its report on data from 22 agencies that belong to the San Diego County Water Authority.
While the countywide average rose, the increase was greater at some individual agencies. The Equinox Center reported that water use surged 30 percent between fiscal years 2011-14 at the Santa Fe Irrigation District, which serves Fairbanks Ranch, Rancho Santa Fe and Solana Beach; 19 percent in Ramona; and 17 percent in Poway.
In that same period, however, consumption dropped 21 percent in the far North County community of Rainbow, 14 percent in Olivenhein and 12 percent at the Sweetwater Authority, which serves Bonita, National City and parts of Chula Vista.
Broken down by daily use by residential customers, Sweetwater customers consumed the least water in the most recent fiscal year -- 64 gallons. The city of San Diego was second at 73 gallons, according to the study.
The most water used in the last fiscal year was in the Santa Fe Irrigation District, where customers averaged 504 gallons a day. Officials with the agency have said they are on track to meet state water-use mandates.
The Equinox Center recommended that local water agencies develop consistent definitions of customer classes and collect usage data for each class; post the information at least quarterly on their websites; measure the effectiveness of conservation campaigns; make usage data and conservation resources available on their websites; and standardize their conservation messages.
The environmental organization San Diego Coastkeeper said the report shows why mandatory measures for reducing consumption should remain in place as “a new normal.''
“Water-use trends uncovered in Equinox Center's report don't surprise us,'' said Matt O'Malley, waterkeeper for the group. “This is why San Diego Coastkeeper has long advocated for mandatory conservation measures to change water-use habits -- rules that should become the new normal for the region and that cities must enforce.''
He said the new data shows that water officials and residents need to sustain short-term conservation results into the longer term.