The 2018 Legislation (Senate Bill 606 and Assembly Bill 1668) establishes a new framework for long-term improvements in urban water use efficiency and drought planning as California adapts to climate change impacts.
The legislation requires that long-term urban water use efficiency standards be set so that urban retail water suppliers’ urban water use objectives (UWUO; defined below), together with other water uses excluded from the long-term standards, would exceed the statewide 2020 water conservation targets required pursuant to SB X7-7 (California Water Code (WC) §10609.2(d)). (Water uses excluded from the standards include commercial, industrial, and institutional (CII) indoor water use and CII outdoor landscape irrigation water use not connected to a dedicated irrigation meter. These water uses are subject to CII water use performance measures.)
The 2018 Legislation requires DWR, in coordination with the State Water Board, to perform the necessary studies and investigations on the following:
The 2018 Legislation also requires DWR, in coordination with the State Water Board, conduct necessary studies and investigations and develop the following recommendations for adoption by the State Water Board:
The State Water Board, in coordination with DWR, is required to adopt long-term standards, appropriate variances, guidelines, and methodologies for calculating UWUO by June 30, 2022 (WC §10609.2). These standards, variances, and performance measures will become effective following the State Water Board’s adoption of the recommendations through a public rulemaking process.
Urban retail water suppliers are required to calculate their UWUO, assess whether their actual water use met the UWUO, and report the outcome and supporting information in their Annual Water Use Report by January 1 of each year, starting in 2024 (WC §10609.24(a)). This UWUO is based on an aggregate estimate of efficient urban water use for the previous year (calendar or fiscal year) based on the adopted urban water use efficiency standards and local service area characteristics for that year (WC §10609.20).
The annual UWUO (WC §10609.20(c)) is the sum of the following:
The 2018 Legislation also allows urban retail water suppliers to adjust their UWUO by adding an allowable portable reuse bonus incentive (WC §10609.20(d)). By comparing the amount of water used in the previous year with the UWUO plus the potable reuse bonus incentive, where applicable, urban retail water suppliers will be in a better position to help eliminate unnecessary use of water (WC §10609(a)).
Urban retail water suppliers are also required to report their progress in the several performance measures for CII water use that are not included in the UWUO, covering the following (WC §10609.10).
Performance measures are actions to be taken by urban retail water suppliers that will result in increased water use efficiency by CII water users and they do not include process water (WC §10608.12(n)). The use of performance measures is to recognize the diversity and complexity associated with CII water use and its potential connection to economic productivity.
Per the 2018 Legislation, DWR has prepared and transmitted the following reports to the Legislature for further consideration:
On September 29, 2022, DWR provided recommendations developed in response to the 2018 Legislation to the State Water Board in a memorandum that also summarizes the background and robust public process to support the development of these recommendations.
Full reports detailing DWR methods, technical analyses, studies, public input, and recommendations were completed in September 2022, and transmitted to the State Water Board on October 28, 2022.
To streamline document development, DWR organized the various reports into an Urban Water Use Efficiency Recommendation Package (Recommendation Package) that allows mutual referencing and incorporates content by reference. All reports in this Recommendation Package are given a serial number (e.g., WUES-DWR-2021-xx). For each report, Appendix A includes the list of documents within the Recommendation Package that are incorporated by reference. A complete list of the reports in the Recommendation Package is included in a PDF here for reference. Links to the reports in the Recommendation Package are posted below.
In coordination with the State Water Board, DWR developed the recommendations for urban water use efficiency standards, variances, and performance measures with the collaboration with many workgroups and input from interested parties.
DWR developed recommended standards for outdoor residential water use efficiency (WC §10609.6) and CII outdoor irrigation of landscape areas with dedicated irrigation meters (WC §10609.8). Both standards incorporate principles of the Model Water Efficient Landscape Ordinance (MWELO) and other requirements provided by the 2018 Legislation.
DWR was also required to provide aggregate measurements of residential irrigable area to each urban water retail supplier. DWR undertook a statewide residential landscape area measurement project (LAM) to determine these aggregate measurements as outlined in the LAM Technical Report below.
DWR developed recommendations for appropriate variances for unique uses that can have a material effect on an urban retail water supplier’s UWUO and the corresponding thresholds of significance (WC §10609.14). In this context, DWR interpreted that a material effect means that a unique water use, although used in an efficient manner, when not explicitly addressed and calculated separately based on the four water use efficiency standards in an affected urban retail water supplier’s UWUO, could unfairly jeopardize a supplier’s ability to meet the UWUO. Through stakeholder input, DWR refined the list of appropriate variances and suggested protocols for considering future variances.
DWR developed recommendations for guidelines and methodologies to account for bonus incentive available to urban retail water suppliers implementing potable reuse to adjust their UWUO (WC §10609.20(d)).
For CII water use not associated with process water or outdoor irrigation of landscape areas with dedicated irrigation meters (already included as one of the outdoor water use standards), DWR developed recommendations on performance measures to support the CII sector’s progress towards improved water use efficiency (WC §10609.10). The 2018 Legislation recognizes the need to manage CII water use separately from other water use captured under the UWUO because CII water use can be both complex and diverse. In addition, there is a lack of available information to properly set the type of standards or variances as done for other categories of water use. Performance measures ensure progress is being made toward improving CII water use efficiency.
The 2018 Legislation required DWR to provide or otherwise identify data regarding the unique local conditions to support the calculation of an urban water use objective (CWC 10609. (b)(2) (C)). The urban water use objective (UWUO) is an estimate of aggregate efficient water use for the previous year based on adopted water use efficiency standards and local service area characteristics for that year.
The dataset provided in the link below enables urban retail water suppliers calculate efficient outdoor residential water use, efficient outdoor irrigation of landscape areas with dedicated irrigation meter for CII water use, and some variances for their service area. DWR will provide technical assistance for estimating the remaining UWUO components, as needed.
The 2018 Legislation required DWR to demonstrate that recommended long-term efficiency standards lead to greater conservation savings than those achieved by the SB X7-7’s 20 percent by 2020 targets.
DWR developed the DWR Urban Water Use Objective Analyzer tool to, among other things, evaluate alternative standards in relation to the statewide SB X7-7 target. This spreadsheet model utilizes the various data sources to estimate Urban Water Use Objective and Objective Based Total Water Use for the State’s urban retail water suppliers. The “Read Me” tab of the spreadsheet provides description of the data sources used in the Data Analyzer.
For additional details, see DWR reports “Recommendations for Urban Water Use Efficiency Standards, Variances, Performance Measures, and Annual Water Use Reporting (Report No. WUES-DWR-2021-01A)” and “Recommendations for Outdoor Residential Water Use Efficiency Standard (Report No. WUES-DWR-2021-02)”. These reports are also linked above.
Find general contact information in the directory, or select the button below to email WUE.
The Department of Water Resources (Department) welcomes all public comments on the third draft of revisions to the MWELO. Consistent with Office of Administrative Law guidelines, only comments related to the revised language provided in this notice will be considered. Comments deemed by the Department to cause a material change to existing MWELO ...
Join the Department of Water Resources for the second Drought Resilience Interagency & Partners (DRIP) Collaborative meeting of 2024. Members of the public will be able to observe the meeting and provide public comments in-person at the meeting location or remotely.
The Drought Resilience Interagency & Partners (DRIP) Collaborative will hold a workgroup meeting to refine proposed recommendations under the Drought Relevant Data Focus Area.
The Drought Resilience Interagency & Partners (DRIP) Collaborative will hold a workgroup meeting to refine proposed recommendations under the Drought Definition and Narrative Focus Area.
The Drought Resilience Interagency & Partners (DRIP) Collaborative will hold a workgroup meeting to refine proposed recommendations under the Drought Preparedness for Domestic Wells Focus Area.
The Drought Resilience Interagency & Partners (DRIP) Collaborative will hold an informational meeting for DRIP Collaborative member-volunteers for the recently formed workgroups based on the following focus areas; Drought-Relevant Data, Drought Preparedness for Domestic Wells, and Drought Definition and Narrative.
DWR has proposed amendments to California Plumbing Code (CPC) sections dealing with plumbing design standards for recycled water. A 45-day comment period ending July 1, 2024 is the public’s chance to review and provide feedback to DWR on these proposed changes. The CPC supports local building and planning departments, as well as potable and recycle ...
Join the Department of Water Resources for the first Drought Resilience Interagency & Partners (DRIP) Collaborative meeting of 2024. Members of the public will be able to observe the meeting and provide public comments in-person at the meeting location or remotely.
The Department of Water Resources has published rulemaking documents for a supplemental 15-day comment period for the proposed amendments to the MWELO. The written comment period commences on March 19, 2024, and will close on April 3, 2024.
The Department of Water Resources has published rulemaking documents for proposed amendments to the Model Water Efficient Landscape Ordinance. A written comment period commences on November 17, 2023, and closes on January 16, 2024.