The San Diego County Water Authority’s draft 2020 Urban Water Management Plan was released for public review today. The plan highlights how regional investments in a “water portfolio approach” to supply management and a sustained emphasis on water-use efficiency mean that San Diego County will continue to have sufficient water supplies through the 2045 planning horizon — even during multiple dry years.

A 60-day public comment period on the draft plan ends May 6 and will include a public hearing on March 25. The Board of Directors is expected to consider adoption of the final plan during its regular meeting on May 27. The 2020 UWMP is due to the state by July 1, 2021. To read the draft 2020 Urban Water Management Plan, or to submit comments, go to http://bit.ly/Water-Authority-UWMP.

Regional investments pay off for water supply

“Thanks to decades of regional investments, the draft plan shows that we don’t need to secure more regional supply sources for the foreseeable future,” said Water Authority General Manager Sandra L. Kerl. “Instead, we are focused on helping our member agencies develop local supplies and looking for other ways we can continue to ensure supply reliability at a reasonable cost.”

The Water Authority started the current UWMP process in September 2018, coordinating closely with its 24 member agencies, most of which must submit their own plans to the state. Member agencies provided input into the draft plan as part of the Water Authority’s ongoing effort to align local and regional projections as closely as possible. The plan’s long-range demand forecast shows an increase in regional demands of less than 1% per year through 2045. This change in demand is consistent with the change forecasted by other large water suppliers, including the City of San Diego and the Metropolitan Water District of Southern California.

Plan is mandated by state law

Multiple supply and demand projections factor into Urban Water Management Plans, which are mandated by the state to ensure sufficient supplies over 25 years. The plans are not used to set water rates; rates are set annually based on multiple financial factors at the time, not long-term projections about water supplies.

Urban Water Management Plans are dictated by statutory guidelines, Water Authority Board direction and an agreement with the San Diego Association of Governments to use its regional growth forecast. The plans also support state laws that link approval for large housing developments to water supply availability.

By law, the plans must be updated every five years. Per state guidelines, the Water Authority’s Urban Water Management Plan includes:

• Projected water demands under normal weather and dry weather scenarios
• Conservation savings information
• A process to conduct an annual water supply and demand assessment
• Supply reliability analysis

The demand forecast accounts for changes in socio-economic factors, such as the number of projected housing units, the mix of single-family and multi-family dwellings, and employment growth.

Conservation by water ratepayers in San Diego County

Conservation projections account for continued adoption of water-use efficiency measures, compliance with landscape water-use ordinances for new residential construction, and continued installations of sustainable landscapes at existing homes. Since 1991, San Diego County ratepayers have conserved more than 1 million acre-feet of water, and per capita potable water use in the region decreased nearly 60% between fiscal years 1990 and 2019.

The draft 2020 UWMP also highlights the value of the Water Authority’s long-term strategy to invest in highly reliable and locally controlled supplies from the Claude “Bud” Lewis Carlsbad Desalination Plant and the nation’s largest conservation-and-transfer agreement, which provides high-priority, low-cost water from the Colorado River.

In addition to the UWMP, the Water Authority also regularly updates its Regional Water Facilities Optimization and Master Plan, which focuses on the infrastructure necessary to meet projected long-term demands, and its Long-Range Financing Plan. Those documents work together to ensure the right mix of supplies and facilities to meet the region’s needs at an affordable cost.