Case Study:
Irvine Ranch Water District
Effectiveness of Budget-Based Rates

Submitted by IRWD

In 2001, IRWD consolidated with the former Los Alisos Water District (LAWD). As part of the consolidation agreement, the LAWD portion of IRWD’s service area remained on its existing conservation tiered rate structure until the full acquisition balance was paid off. LAWD customers benefitted from the same comprehensive and aggressive conservation programs and outreach as the rest of the service area. A 2008 study prepared for IRWD compared the water use in the LAWD portion of the service area, which had standard conservation tiered rates and the same conservation programs, with the rest of the IRWD service area which was on the BBR Structure. The study concluded that the BBRs accounted for an 8.8% lower demand for single family customers and 31.5% lower demand for non-residential outdoor water use.

The BBR structure has proven to be an extremely effective tool to promote water conservation and reduce overall demands in IRWD’s service area. Since IRWD adopted a BBR structure in 1991, landscape water use has dropped by 68% from 4.4 AF per acre to an average of 1.8 AF per acre in January 2016. Residential gallons per capita per day has dropped 50% from 118 gallons per capita per day prior to implementation of the rate structure to 59 gallons per capita as of January 2016.