State Water Board - Measurement Regulation


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Core Documents

On January 19, 2016, the State Water Board adopted a Resolution to adopt an Emergency Regulation for Measuring and Reporting Water Diversions. On March 10, 2016, the regulation was submitted to the Office of Administrative Law (OAL) for review. The OAL approved this regulatory action on March 21, 2016.

Key Provisions of Regulation

Annual Water Use Reporting Requirements for Water Right Holders

All water right holders shall report on their diversion and use of water annually, beginning with reports for the 2016 diversion season. Annual water use reports for permits, licenses, registrations and stock pond certificates must be filed by April 1 of each year starting April 1, 2017 for diversions made in 2016. The annual use reports for statements shall be filed prior to July 1 of each year. All reports will continue to document diversions during the prior calendar year. The filing dates are for the annual water use reports are summarized below:

2015 JULY 1, 2016 JULY 1, 2016 JULY 1, 2016 VARIES NOT REQUIRED
2016 APRIL 1, 2017 APRIL 1, 2017 JULY 1, 2017 APRIL 1, 2017 APRIL 1, 2017

Reporting Requirements for Water Right Holders During Times of Insufficient Supply

When the amount of water available in a surface water source is not sufficient to support the needs of existing water right holders and in-stream uses, the State Water Board may require monthly or more frequent reporting in the affected areas to provide the most accurate assessment of water demand. The State Water Board will notify diverters in affected areas when additional reporting is required.

Deadline for Complying with Measurement and Reporting Requirements

The regulation provides for a phased approach to compliance. The compliance deadlines, by volume of water diverted, are shown in the table below.

Required Accuracy for Measurement and Frequency for Monitoring

SB 88 set expectations for both the accuracy of measurement devices as well as the monitoring frequency of the device. The regulation links both device accuracy and monitoring frequency to the volume categories in the table above. Larger diversions and larger reservoirs or ponds have more stringent measurement and monitoring requirements and more stringent requirements for the installation and certification of measurement devices as described in the table below.

Type of Diversion
(af = acre-feet)
Installation Deadline Required Accuracy
(Device Installed On/Before 1/1/2016)
Required Accuracy
(Device Installed After 1/1/2016)
Required Monitoring
Qualifications For Installation
And Certification
Direct Diversion
>= 1,000 af/year
Storage >= 1,000 af
January 1, 2017 15% 10% Hourly Engineer/Contractor/Professional/
Passed AB 589 Measurement Class
Direct Diversion
>= 100 af/year
Storage >= 200 af
July 1, 2017 15% 10% Daily Engineer/Contractor/Professional/
Passed AB 589 Measurement Class
Storage >= 100 af July 1, 2017 15% 15% Weekly Engineer/Contractor/Professional/
Passed AB 589 Measurement Class
Direct Diversion
> 10 af/year
Storage >= 50 af
January 1, 2018 15% 15% Weekly Individual experienced with
measurement and monitoring
Storage > 10 af January 1, 2018 15% 15% Monthly Individual experienced with
measurement and monitoring

Measurement Methods

Diverters may propose a measurement method, in lieu of a measuring device, to comply with measurement and accuracy requirements under the regulation. Examples of measurement methods include:

  • Multiple water right holders on a single surface supply can propose a collaborative measurement approach.
  • A single water right holder with multiple points of diversion can propose a measurement method that may preclude the need to install a measurement device at each point of diversion.

Alternative Compliance

A water right holder may request an alternative compliance approach when strict compliance is not feasible, would be unreasonable expensive, would unreasonable affect public trust resources, or would result in the waste or unreasonable use of water.

Alternative Compliance Plans must be submitted on the Division's Water Right Form and Survey Submittal Portal. Please note: Persons subject to the regulation are not allowed to claim "not locally cost effective."

Alternative Compliance Plans received by the State Water Board are posted on the following page:

Certification of Water Measurement Device

The regulation requires that the accuracy of the water measurement device be certified every five years, in accordance with the table above. The regulation calls for an initial certification with the first water use report filed after the device has been installed.


Senate Bill 88 was signed by Governor Edmund G. Brown Jr. on June 24, 2015. Sections 15 through 18 of SB 88 add measurement and reporting requirements for a substantial number of diverters.

The legislation authorizes the State Water Board to adopt a regulation requiring measurement for water right holders and claimants who divert 10 acre-feet of water or more per year. The measurement requirement applies to approximately 12,000 water right holders and claimants. The legislation also authorizes the State Water Board to adopt a regulation requiring annual reporting from statement holders and persons authorized to appropriate under a permit, license, registration (small domestic, small irrigation, or livestock stockpond), or certificate for livestock stockpond use.

The legislation authorizes the State Water Board to adopt an initial regulation as an emergency regulation that shall remain in effect until revised by the State Water Board. The adoption of the initial regulation is exempt from the California Environmental Quality Act (CEQA)

The State Water Board anticipated that the new measurement requirements could present challenges to the regulated community. The State Water Board held meetings and workshops in affected areas around the state to receive input on key issues to be addressed in the emergency regulation. See the Meetings and Workshops section below for more information. The State Water Board will use the input from the meetings and workshops to shape a draft regulation which will be broadly circulated around the State in early December. The draft regulation was presented for discussion at a State Water Board Workshop on December 17, 2015.

On January 19, 2016, the State Water Board approved a Resolution to adopt an Emergency Regulation for Measuring and Reporting Water Diversions. On March 10, 2016, the State Water Board submitted the proposed regulation to the Office of Administrative Law (OAL) for review. The OAL approved this regulatory action on March 21, 2016.

The Current Problem

California's recent extended drought has highlighted the need for more current and accurate information on how much water is being diverted in the various watersheds throughout the State. Even during years with more normal precipitation, rainfall and snow accumulation patterns vary widely across the State. Even though water supply may be adequate in one region, a critical water shortage can occur in another region.

More accurate data on water diversions is needed on a timely basis for all users of water in the State to evaluate how far their water supplies can be expected to stretch. As a user of water in the State, this diversion information together with an understanding of the priority of right to use a limited water supply, will allow for better water use planning decisions. This information is critical to ensure that priority water needs are met, that water rights holders have access to the information indicating whether sufficient water is likely to be available for their beneficial uses, and to ensure that adequate flows remain instream for more senior downstream beneficial uses.

During the 2015 drought, the State Water Board called upon the water use community to provide predictions of expected surface water diversion, and to report back on the amounts that were actually diverted. This more current information shows that the historic reporting standard does not provide accurate or timely water demand data sufficient for drought response. The new law and proposed implementing regulation is expected to address this problem.


Benefits of Measurement and Reporting

The State Water Board is the agency with primary responsibility for the administration and regulation of water rights in California. The State Water Board allocates surface water through a system of permits, licenses, and registrations that grant and condition the right to directly divert water and/or to divert water to storage for reasonable beneficial use. In addition, the State Water Board maintains records of water use under riparian and pre-1914 claims of right.

The implementation of improved measurement and reporting of water rights as required under Senate Bill 88 and a proposed emergency regulation to implement the new law will improve water right administration and transparency of diversion records. More accurate and current diversion records together with their transparency allow the State Water Board and all water users to more effectively:

  • Understand and plan ahead for limited water supplies;
  • Identify water losses in a diversion system and take corrective actions to conserve water and stretch limited water supplies;
  • Assure compliance with the quantity and season limitations of existing water rights;
  • Protect the senior rights of diverters in accordance with their relative priorities;
  • Provide for efficient management and use of water during times of shortage; and
  • Improve water planning and near-term forecasting of water demand.

Meetings and Workshops

The State Water Board held five public meetings to provide the public opportunity to help formulate the proposed regulation to implement the measurement and reporting authority under Senate Bill 88.

November 2, 2015 (Monday)
6:00 - 9:00 pm

Junipero Serra State Office Building, Carmel Room
320 West 4th Street, Los Angeles, CA 90013

November 4, 2015 (Wednesday)
6:00 - 9:00 pm

The City of Redding
777 Cypress Avenue, Redding, CA  96001

November 5, 2015 (Thursday)
6:00 - 9:00 pm

State Office Building, Auditorium
31 East Channel Street, Stockton  95202

November 9, 2015 (Monday)
1:00 - 4:00 pm
CalEPA Building, Coastal Hearing Room
1001 I Street, Sacramento, CA 95812
A webcast of the meeting on November 9 in Sacramento was available at
November 12, 2015 (Thursday)
6:00 - 9:00 pm

Steele Lane Community Center
415 Steele Lane, Santa Rosa, CA  95403

  • Technical Workshop - October 16, 2015
  • Delta Preliminary Stakeholder Meeting - October 8, 2015
  • Initial Stakeholder Meeting - October 6, 2015

State Water Board Contact Information