Water Loss Control

Updated Water Loss Model (Released September 2, 2022)

Model Equation Changes (Released September 2, 2022)

Individual System Water Loss Standards (Released April 9, 2024)

Questionnaires

Urban retail water suppliers are required to complete questionnaires administered by the State Water Resource Control Board (California Code of Regulations, title 23, division 3, chapter 3.5, section 983). The deadline for submitting the data quality and pressure management questionnaires has been extended to December 31, 2023. If a supplier has multiple systems, it must complete this questionnaire once for each system.

Data Quality Questionnaire

This system-level questionnaire asks for information on flow testing of production meters, electronic calibration, flow testing of customer meters.

A summary of the questions in the data quality questionnaire is available here

Pressure Management Questionnaire

This system-level questionnaire asks for information on pressure control devices and high leakage zones.

A summary of the questions in the pressure management questionnaire is available here

Data Quality Excel Submission

The Data Quality Excel Submission is a component of the Data Quality Questionnaire. Please refer to the Data Quality Questionnaire for instructions regarding the Data Quality Excel Submission.

Asset Management Questionnaire

This system-level questionnaire asks for information on distribution infrastructure leak records maintenance and replacement prioritization.

A summary of the questions in the asset management questionnaire is available here

Directions for Updating Default Parameters

Default parameters in the Economic model may be updated to incorporate supplier-specific information. Additionally, suppliers may request to remove outlier values. Supplier must provide an explanation for default parameters submitted after July 1, 2023. We are asking that suppliers submit requests as soon as possible. An updated guidance document is available for reference.

A reference document for outlier values is available here.

A reference document for economic model inputs is available here.

To submit a request, please email DDW-WaterLossControl@waterboards.ca.gov

Please refer to the Frequently Asked Questions document for questions related to the water loss standards and regulation

Please refer to the presentation from the October 2022 board hearing for a summary of the water loss regulation and changes that were made during the rulemaking process.

Subscribe to the Water Loss Control Updates email topic to receive notifications and the latest updates.

Email Address

April 15, 2021 - Updated Economic Model

Memo for Economic Model Release
Revised Economic Model

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March 24, 2021 - Public Stakeholder Webinar

Notice

Documents for March 24 Staff Workshop on Water Loss
Attached are the peer reviews and a staff summary that will be discussed at the workshop on March 24 from 1:00pm-3:00pm. For questions about these documents or the workshop, please contact Bethany Robinson at Bethany.Robinson@waterboards.ca.gov

Water Loss Staff Summary of Peer Reviews
Water Loss Peer Reviews

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December 16, 2020 - Public Stakeholder Webinar

Agenda | Notice

Presentations

Revised Economic Model: Water Loss Performance Standards
Revised Regulatory Proposal and Process: Water Loss Performance Standards

Reference materials:

1. Fact sheet with overview of regulatory proposal and timeline
2. Draft economic model to calculate water loss standards
3. Summary of changes to economic model
4. Draft Guidance to draft economic model
5. Draft proposed water loss standards using default values in economic model
6. Questionnaires on:
   1. Data quality
   2. Asset management
   3. Pressure management
7. Draft regulatory text
8. Proposed alternative compliance pathway for existing low loss
9. Draft Initial Statement of Reasons

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May 13, 2020 - Public Stakeholder Webinar

Agenda | Revised Notice (Comment period extended to June 12, 2020) | Notice

Voluntary questionnaire for additional information on water loss audits

The purpose of the voluntary questionnaire is to support the State Water Board's efforts towards assessing and establishing the reliability of and confidence in the water loss estimates reported in the water loss audits.

Materials for comment:

1. Proposed Water Loss Performance Standards: Overview and Timeline
2. Draft economic model for calculating volumetric standards (second version)
   (The model contains proposed default values for inputs and uses example values for supplier-specific input values from water loss audits - see item 6 for all values)
3. Questionnaires for data submission requirements of the proposal on:
   1. Data quality (Apparent loss)
   2. Asset management
   3. Pressure management
4. Overview of proposed off-ramp provision
5. Summary of current leakage and proposed draft volumetric standards for urban retail water suppliers
6. Input values from water loss audits used to calculate proposed draft standards

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September 23, 2019 - Public Stakeholder Meeting #6

Agenda | Revised Notice | Notice

Reference material for the workshop was circulated through State Water Board's conservation list serve. Sign up for the email list at https://www.waterboards.ca.gov/resources/email_subscriptions/swrcb_subscribe.html

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June 7, 2019 - Public Stakeholder Meeting #5, Sacramento

Agenda | Notice

Materials for workshop (Uploaded June 11, 2019): The uploaded materials are documents that were shared during or prior to the workshop. The following materials are subject to changes based on stakeholder input, as the stakeholder process is ongoing.

• Overview of framework
• Reference document describing preliminary assumptions and proposals for standard development
• Initial assumptions and considerations for calculations of benefits and costs for the economic model
• Calculation of standards, overview of compliance requirements and low water loss values
• Adjustments and variance process

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February 1 and 4, 2019 - Public Stakeholder Meetings #4, Sacramento and Chino

Agenda | Notice

The uploaded materials are documents that were shared during or prior to the workshop. The following materials are subject to changes based on stakeholder input, as the stakeholder process is ongoing.

• Staff proposal for framework of water loss performance standards
• Staff presentations:
  Framework overview | Adjustments and Compliance | Economic basis

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September 17, 2018 - Public Stakeholder Meeting #3, Los Angeles

Agenda

Presentations:

• Avoided Cost of Water,  State Water Resources Control Board
• IRWD’s Water Loss Control Programs and Cost-Effectiveness,  Irvine Ranch Water District
• Water Loss Control in Los Angeles, LA Department of Water & Power
• Overview of Life Cycle Cost Assessment: Case Study of LCA Alternatives Assessment of Lead-Free Cast Brass for the Potable Water Supply Components, University of California Los Angeles

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June 1, 2018 - Public Stakeholder Meeting #2

Agenda | Notice

• Monitoring and Estimation Technologies |  Pressure management |  Technology-Constraint Matrix, State Water Resources Control Board
• Machine learning and Pipeline Replacement Prioritization, East Bay Municipal Utility District

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March 9, 2018 - Public Stakeholder Meeting #1, Sacramento

Agenda

• Water audit data and topics, State Water Resources Control Board
• Water Loss TAP findings, WSO