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Water Measurement Regulations

All water right diverters who are authorized to divert more than 10 acre-feet per year from watercourses must comply with Senate Bill 88 measurement regulations. Measuring and monitoring regulations are in Title 23 of the California Code of Regulations, sections 931-938. To learn more about the background, development, and purpose of the measurement regulations, please reference the Regulatory Background Section.

The State Water Resources Control Board (State Water Board) Division of Water Rights relies on diversion measurements and annual reports for water resource planning and to keep diverters informed, particularly in times of drought. (Annual use reports are required under Cal. Code Regs., Title 23, § 920 [Supplemental Statements of Water Diversion and Use], § 924 [Water Use Reports of Registration and Certificate Holders], § 925 [Progress Reports by Permittee], § 929 [Reports of Licensee]).

The Division of Water Rights maintains a searchable list of water rights and/or claims of right it believes are subject to the Senate Bill 88 Measurement Regulations but appear to have either made no attempt at complying or have indicated measuring devices have been installed but the required associated datafiles have not been submitted.
  Please see our Water Measurement Regulations web page for more information on the requirements.
  If you believe your water right or claim of right is on this list in error, please email the Division at DWR-Measurement@waterboards.ca.gov.

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Submit your reports to the eWRIMS Report Management System (RMS)

All diverters are required to submit these reports, even for years in which no water was diverted.

Contact Us for assistance

Failure to measure and report your water diversion and use is a violation subject to fines and other consequences.

Do Measurement Regulations apply to you?

If you do not know which type of water right you have or know how much your water right is for, go to this document for assistance: Know Your Water Right


If you have a single water right or single claim of right, you need to measure your water diversion if:

You are authorized to divert greater than 10 acre-feet of water per year under a permit or license,
OR
You file a Statement of Water Diversion and Use (Statement) and you have previously diverted or intend to divert greater than 10 acre-feet. If you just bought the property, the determination would be what you intend to divert; you may look at previously reported or measured diversion quantities to estimate if your future uses will be greater than 10 acre-feet,
OR
You are authorized to divert greater than 10 acre-feet of water per year or have a storage facility with a capacity greater than 10 acre-feet under a registration.


If you have multiple water rights and/or claims that serve the same place of use or use the same point of diversion, you need to measure your diversions if:

The sum of your multiple rights and/or claimed rights to divert from the same point of diversion or serving the same place of use exceeds 10 acre-feet per year in total. (Cal. Code Regs., Title 23, § 932.)


If your diversion is watermastered and your watermaster reports annually on your behalf:
You do not have to measure your diversions under measurement regulation requirements. Contact your watermaster to confirm. Note that annual reports are still required for diversions under a permit, license, registration, or certificate in a watermaster service area. (Cal. Code Regs., Title 23, §§ 924-926.)

Steps to Comply with Measurement Regulations

Before installing a measurement device, we suggest doing the following: identify your Qualified Individual, determine how much water is associated with your water right or claimed right, and determine your measurement requirements. Once you have done those three things, you can work with the Qualified Individual to determine the best way to comply with the measurement regulations that also suits your needs and operation. This may be either installing a measurement device, implementing a measurement method, or filing an alternative compliance plan. The last step is to report your water diversions and use and submit a datafile.

  1. Identify your Qualified Individual
  2. Determine how much water is associated with your water right or claimed right
  3. Determine your measurement requirements
  4. Measure your diversion
  5. Report to the State Water Board

1. Identify your Qualified Individual

Measuring water diversions can be complex, the accuracy of a measurement device can vary based on conditions specific to your diversion and requires technical expertise. The measurement regulations require a “Qualified Individual” to complete multiple steps in the measurement process. Table 1 describes who can be a Qualified Individual for your diversion.

Table 1. Qualified Individual Definition (Cal. Code Regs., Title 23, § 931, subd. (l))

Diversion Amounts Who is a Qualified Individual?
Diversions greater than or equal to 100 acre-feet per year
  • California registered Professional Engineer
  • A person under the supervision of a California registered Professional Engineer and employed to install, operate, and maintain water measurement and reporting devices or methods
  • A California licensed contractor for C-57 well drilling
  • A California licensed contractor for C-61 Limited Specialty/D-21 Machinery and Pumps
  • Any water right owner, diverter, tenant or employee thereof can become qualified by completing a training course on measurement devices offered by the University of California Cooperative Extension
Diversions less than 100 acre-feet per year
  • Person trained and experienced in water measurement and reporting. This may include the diverter or the diverter’s agent. A training class is not required but is recommended.
Federal Agency Water Rights
  • Hydrologist or professional engineer experienced and trained in water measurement who is employed by the federal agency in that capacity.

How to find a Qualified Individual

The Division of Water Rights maintains lists of consultants and attorneys that practice in water rights.

Please note, this list is maintained for your convenience. The State Water Board does not endorse any of the professionals on the list and you may find other professionals suited for your needs. If you hire any of the professionals on the list, you should ensure that they have qualifications outlined in the above table

How to Become a Qualified Individual

You can become a Qualified Individual by completing a training course on measurement devices offered by the University of California Cooperative Extension and understanding the mechanics of measuring devices. A list of upcoming training classes and registration information are available on the University of California Cooperative Extension website.

Steps that Require a Qualified Individual

Multiple steps in complying with measurement regulations depend on a Qualified Individual. The following list details steps that must be done by a Qualified Individual:

  • If you are employing a Measurement Device (Cal. Code Regs., Title 23, § 933)
    • Installation of a Measurement Device (Cal. Code Regs., Title 23, § 933, subd.(g))
    • Calibration at least once every five years or as often as necessary to ensure the measurement device meets accuracy requirements (Cal. Code Regs., Title 23, § 933, subd. (h))
    • Volume Conversion Method (if applicable) (Cal. Code Regs., Title 23, § 933, subd. (c))
    • Certification of Accuracy requires a qualified individual (Cal. Code Regs., Title 23, § 933, subd. (e))
      • If your measurement device’s accuracy can be certified using laboratory methods a qualified individual is not required and was installed after 2016 (Cal. Code Regs., Title 23, § 933, subd. (e) (2) (A)),
    • Field testing, field-inspection, analysis (Cal. Code Regs., Title 23, § 933, subd. (f))
  • If you are employing a measurement method (Cal. Code Regs., Title 23, § 934)
    • Preparation of Measurement Method Form (Cal. Code Regs., Title 23, § 934, subd. (b))
    • Certification of Accuracy (Cal. Code Regs., Title 23, § 934, subd. (e-f))
    • Operation and Performance Requirements (Cal. Code Regs., Title 23, § 933, subd. (g))
  • If you are filing an alternative compliance plan (Cal. Code Regs., Title 23, § 935)
    • Certification of the Alternative Compliance Plan (Cal. Code Regs., Title 23, § 935, subd. (c))

2. Determine how much water is associated with your water right or claimed right

Your reporting requirements depend on the volume of your diversion. If you are not familiar with the details of your water right or claim of right, please follow this guide:
Know Your Water Right
Once you know the quantity of water associated with your water right or claim of right, continue to Step 3.

3. Determine your measurement requirements

Before the Qualified Individual selects a measurement device, it is important to know the measurement accuracy and monitoring frequency that is required for the diversion. Use Table 2 to determine the accuracy and frequency your measuring device must provide.

Table 2. General Measurement Requirements

Diversion Amounts Installation Deadline Required Accuracy Required Monitoring Frequency** Qualifications for Installation
and Certification

Direct Diversion ≥ 1,000 acre-feet/yr or Storage ≥ 1,000 acre-feet*

January 1, 2017

+10%
(15% if installed before 1/1/2016)

Hourly

Who is a “Qualified Individual?”

Direct Diversion ≥ 100 Acre-feet/yr or Storage ≥ 200 acre-feet/yr

July 1, 2017

+10%
(15% if installed before 1/1/2016)

Daily

Storage > 100 acre-feet

July 1, 2017

+15%

Weekly

Direct Diversion > 10 acre-feet/yr
Storage ≥ 50 acre-feet

January 1, 2018

+15%

Weekly

Storage > 10 acre-feet

January 1, 2018

+15%

Monthly

All diversions 10 acre-feet or less

**No measurement required
(exceptions are listed below)

 

* Telemetry: Please refer to the Telemetry Webpage
**Exceptions to this table are listed below. This guide does not replace existing permit or license terms that establish additional monitoring requirements.
Northern California Coastal Streams – Hourly monitoring is required for all new permits in the AB 2121 area.
Cannabis Registrations – Daily monitoring is required

4. Measure your diversion

There are three different ways you can measure your diversion and comply with the measurement regulations:

  1. Measurement Device
  2. Measurement Method
  3. Alternative Compliance Plan

For most diverters, installing a Measurement Device and following the requirements in Cal. Code Regs., Title 23 § 933 is the simplest, accurate and economical way to comply with measurement regulations.

In some situations, a Measurement Device at every point of diversion may not be the most economical or the best technical way to measure and report your water diversion and use. The measurement regulations provide two alternative methods to achieve compliance with measurement regulations: implementing a Measurement Method or submitting an Alternative Compliance Plan.

The Qualified Individual should be able to recommend the best path to compliance for your situation.

Measurement Device (Cal. Code Regs., Title 23, §933)

Once you or the Qualified Individual have determined the accuracy and monitoring requirements that apply to your diversion(s), the Qualified Individual should be able to help you select and install the one that is most economical and fitting for your needs.

All measurement devices must be installed by a Qualified Individual (Cal. Code Regs., Title 23, § 933, subd. (g)). Field testing must be overseen by a Qualified Individual according to the manufacturer’s recommendations or design specification. Field inspection and analysis also must occur to ensure that the design standards, installation standards, operation protocols, and maintenance protocols result in the measuring device meeting the required accuracy standards. The results of the field inspection and analysis must be approved by a Qualified Individual (Cal. Code Regs., Title 23, § 933, subd. (f)). The Qualified Individual must certify the accuracy of the Measurement Device in a Report of Measurement Device.

Many diverters have questions regarding what type of measurement device they should use, where those devices can be purchased, and who can install them. There are many types of measuring devices on the market, some devices are very complex. The type of device you use should reflect the size of your diversion and your reporting requirements.

The Division of Water Rights does not recommend any specific brand, model, or type of measurement device. Nor does the Division of Water Rights recommend specific consultants or engineers that can help with installation. However, the Division of Water Rights does maintain a list of typically used measurement devices as a reference. A list of water measurement device vendors is also provided.

Measurement Device Checklist

Measurement Device Checklist

Qualified Individual installs Measurement Device

Field testing, field inspection, and analysis by the Qualified Individual

Volume Conversion Method (if applicable) approved by Qualified Individual

Certification of Accuracy by the Qualified Individual

Submitting Measurement Device Information with your Annual Water Diversion and Use Report

After 5 years (or as often as necessary to meet accuracy requirements), calibration by the Qualified Individual

Measurement Methods (Cal. Code Regs., Title 23, § 934)

Instead of using a measurement device, a diverter may use a Measurement Method (Cal. Code Regs., Title 23, § 934, subd.(f)). A measurement method is any type of method that measures the amount of water diverted without installing a measurement device at each point of diversion, or is used to describe how water diverted under multiple rights at a single POD is disaggregated among the individual rights. The Qualified Individual must certify that the accuracy of the measurement method is reasonably comparable to the accuracy standards listed above. A measurement method also must record measurements at the same frequency as listed above.

Examples of some measurement methods are listed here. A Qualified Individual can determine if a Measurement Method is appropriate for your diversion(s).

If you are utilizing a Measurement Method, the Qualified Individual must submit a separate form on the Division of Water Rights' Form and Survey Submittal Portal (Cal. Code Regs., Title 23, § 934, subd. (b) (1)). The Deputy Director of the Division of Water Rights may reject Measurement Methods that do not meet the requirements of the measurement regulations (Cal. Code Regs., Title 23, § 934, subd. (b) (2)). Detailed guidance for filling out the form is available here.

Measurement Method Checklist

Measurement Method Checklist

Was a Measurement Method Form prepared by a Qualified Individual submitted to the Division of Water Rights

Does the Measurement Method record the date, time, and total amount of water diverted at the frequency required

Does the Measurement Method record the date, time, and total amount of water diverted at the accuracy required? Did a Qualified Individual certify the accuracy?

Was field testing performed by a Qualified Individual to ensure the Measurement Method reaches the required accuracy?

Does your annual water use report include a formatted datafile containing the measured data?

After 5 years, the Measurement Method must be renewed and the diverter must resubmit the form, with or without amendment

Alternative Compliance Plans (Cal. Code Regs., Title 23, § 935)

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

Alternative compliance plans shall describe how the diverter will attain reasonable compliance with the measurement requirements of the regulation and be accompanied by detailed documentation establishing and supporting the specific basis for requesting the alternative compliance plan.

Alternative compliance plans may be considered for a variety of issues, including measurement and monitoring of small hydropower projects, points of diversion that are inaccessible for portions of the year due to snow, points of diversion with highly variable flow rates, points of diversion under tidal influence, and locations with concerns for vandalism or theft.

Detailed guidance for filling out alternative compliance plans is available here. Alternative Compliance Plans can be filled out and submitted on Division of Water Rights' Form and Survey Submittal Portal.

The Deputy Director of the Division of Water Rights may review, audit, require changes, or reject any plan that does not meet the requirements set in the measurement regulations (Cal. Code Regs., Title 23, § 935, subd. (h)).

Alternative Compliance Plan Checklist

Alternative Compliance Plan Checklist

The plan meets the minimum standards listed in Cal. Code Regs., Title 23, § 935, subd. (b)

The plan is certified by a qualified individual

The plan is submitted on the Division of Water Rights’ Form and Survey Submittal before the deadlines listed in Table 2

After 5 years, the alternative compliance plan must be resubmitted for renewal

5. Report to the State Water Board

The Division of Water Rights develops and maintains online tools to share data and help stakeholders understand what the laws and regulations require. We rely on consistent data from diverters to help us achieve our mission. Monitoring your water diversion and use and fulfilling your legal obligation to accurately report that diversion and use, is more important than ever. When every drop counts, we must be able to count every drop.

The following section provides guidance on how to submit Report(s) of Measurement Device and submit a datafile of your measured data. In your Annual Water Use Report you must report the amount of water you divert per month, provide information about the measuring devices used to measure the diversions, and provide a corresponding datafiles that have measured diversion volumes at the monitoring frequency requirements described in Table 2.

Report of Measurement Device (Cal. Code Regs., title 23, §937)

Diversions must be measured at each point of diversion from which water is diverted under each water right or claim of right. Therefore, depending on your diversion scenario, at least one measurement device will be required to measure your diversions. For diversions to storage, diverters must also have a measuring device or method capable of measuring the rate of withdrawal or release form storage. It is also recommended that diverters to storage have a measuring device or method capable of measuring subsequent diversions of released stored water downstream to support annual reports of total water applied to beneficial use. For larger diverters, this information may be required pursuant to other authorities.

Each measurement device used to measure diversions for a water right or claim of right must be registered with the Water Board by submitting a Report of Measurement Device. This only needs to be done once, then updated if any information changes.

Initial Reports of Measurement Device for each device must be submitted to the Division of Water Rights within the annual report. To add a measuring device to a water right or claim of right, select the “Provide measurement device information/certification” button, shown in the image below. A new form will appear and will ask information about the device, including:

  • Make/model/serial number/type of measurement and recording/logging devices
  • Installation date
  • Accuracy certification
  • Name of device installer
  • Date of most recent calibration/recalibration of measurement device
Supplemental Statement of Water Diversion and Use for 2020 form. Shows where to provide devide information.

Once submitted, a unique Measuring Device ID will be generated for that device. If a measuring device is shared with another right or claim of right, it can be added by selecting the “Import a measurement device from a previously submitted report” button and providing the Measuring Device ID of the shared device.

Datafiles

Submit your Datafile

Diversion volume data must be submitted to the Division of Water Rights within the Annual Water Diversion and Use Report In a format retrievable and viewable using Microsoft Excel or Microsoft Access. A separate datafile is required for each measuring device. Acceptable datafile types are: .csv, .xls, .xlsx, .txt, .dat.

Supplemental Statement of Water Diversion and Use for 2020 form. Shows where to upload data files.
Best Practices for Data Submittal

Do

  • Submit datafiles in machine-readable formats (.CSV, .XLS, .XLSX, .TXT, .DAT)
  • Provide column headings (Date, Time, Device Reading, Units, Amount Diverted, for example)
  • Provide units
  • Diversion to Storage = Change in Volume
  • One datafile per measurement device

Don’t

  • Submit non-machine-readable documents such as PDFs or image files
  • Submit multiple sheets or tables for a single device (for example, don’t split up the data into separate files or Excel worksheets by month)
  • Provide reservoir stage (feet) without translating to volume (acre-feet)
  • Diversion to Storage ¹ Volume of Rervoir
  • Duplicate/aggregated data (for example, multiple values for same cell)

Examples of Good Practices for Submitting Datafiles

Image showing excerpts of datafiles implementing good submittal practices. Column headings are clearly defined. Dates, times, and units are provided.

Examples of Bad Practices for Submitting Datafiles

Image showing excerpts of datafiles implementing poor submittal practices. One file shows a photocopy of a handwritten table, another includes irrelevant data, and another illustrates complex headings.
Templates for Datafiles

Under construction. Coming soon!

Regulatory Background

History and Development of Measurement Regulations

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.

Background and Drought History

Background

Senate Bill 88 (SB 88) was signed by Governor Edmund G. Brown Jr. on June 24, 2015. SB88, now codified as California Code of Regulations, sections 931-938, 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. The draft regulation was presented for discussion at a State Water Board Workshop on December 17, 2015 And 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.

Drought Issues

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, your 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 estimates of anticipated surface water diversion, and to report back on the amounts that were actually diverted. During the drought response, it became apparent that the historic reporting standard did not provide accurate or timely water demand data sufficient for drought management. SB 88 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.