State Water Board Adopts Local Supply-Based Assessment Approach to Conservation Regulation

The State Water Resources Control Board today approved modifications to the existing emergency water conservation regulation to reflect improved conditions and allow for more local decision making.

The modified regulation replaces the existing state-imposed mandatory conservation standards with a locally driven, supply-based assessment process. Urban water suppliers will now be required to self-certify their water supply availability assuming three additional dry years and customer demands based on 2013 and 2014 averages. Local suppliers will then determine the level of conservation needed to assure adequate supply over that time.

The regulation, which takes effect June 1 and will remain in effect through January 2017, does not include a mandatory minimum “conservation floor.” Though the concept of a floor was discussed at today’s hearing, it was not included in the proposal presented by State Water Board staff.

The final regulation closely resembles the State Water Board staff proposal released May 9. It was adopted on a 4-0 vote after several hours of testimony from ACWA members and some non-governmental organizations.

In comments after the vote, State Water Board Chair Felicia Marcus said the board faced a difficult set of decisions, especially in light of the fact that next year’s hydrology is unknown.

“We don’t know whether this year was just a punctuation mark in a mega-drought,” she said. “We don’t want to cry wolf, but we also don’t want to stick our heads in the sand. This allows us to keep our eyes open and create a meaningful discussion about local resilience.”

She said she will take water agencies “at their word that they will continue their messaging” to customers and submit required self-certification data in a transparent manner.

Key Provisions

Under the regulation, urban water suppliers and wholesale suppliers are required to report data and calculations underlying their water supply assessments. Wholesalers are required to submit their data by June 15 (one week later than proposed in the May 9 staff proposal), while urban water suppliers are required to submit their assessment data by June 22 (also one week later than initially proposed.)

Urban water suppliers also are required to continue reporting conservation levels on a monthly basis. Current end-user prohibitions on water waste also will continue.

The new regulation requires individual urban water suppliers to self-certify the level of available water supplies they have assuming three additional dry years. Suppliers that would face a shortage would be required to comply with a conservation standard equal to the amount of that shortage.

Water supply reliability after the 2018-’19 winter would be calculated as follows:

  • The supply projection for the next three years would be based on current supply conditions plus an assumed three-year hydrology mirroring the 2012-13, 2013-14, and 2014-15 water years.
  • Demand over that same period would be based on each supplier’s average total potable water production for 2013 and 2014.
  • Suppliers would factor into their calculations all of their water sources that are capable of being treated to potable standard during the three-year projected period.
  • Suppliers’ conservation standards would be calculated as a percentage and rounded to the nearest whole percentage point.
  • Suppliers would self-certify accuracy of their conclusions and provide their analysis and supporting data.  The State Water Board would post information provided by suppliers on its website and assign each supplier, as a mandatory conservation standard, reductions equal to the suppliers’ projected percentage deficiency in supply at the end of the third dry year.
  • Wholesale water suppliers would be required to make projections about how much water they would deliver to retail water suppliers under the three-dry-years scenario.
  • Option added for a regional approach to compliance with an aggregated regional standard.

Suppliers that do not submit a water reliability certification and supporting information would retain their current conservation standard in almost all cases.

ACWA Members Voice Support for Supply-Based Approach

During today’s hearing on the proposed amended regulation, water agency representatives expressed support for the supply-based approach and thanked State Water Board members and staff for incorporating input from the water community.

“Recognizing local supply is a really big step in the right direction,” Desert Water Agency Outreach and Conservation Manager Ashley Metzger said. “We remain committed to helping our customers conserve. They have become more efficient water users, and we don’t see that changing.”

Water agency representatives said they did not see a need for a mandatory “conservation floor” because it would be inconsistent with the supply-based approach and send a mixed message to customers. The State Water Board could consider the concept in January if the self-assessment process is not yielding the desired results, ACWA members said.  

ACWA Special Projects Manager Dave Bolland said water agencies fully intend to continue sending a strong conservation message to their customers as they transition from the emergency measures to ongoing, aggressive conservation and water use efficiency.

“Agencies won’t be letting up off the gas,” Bolland said.

ACWA member agencies with questions may contact Bolland at (916) 441-4545 or

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