New Laws Increase Water Supply Planning Requirements

On October 9, 2001, the Governor signed into law several bills that trigger new planning requirements for water suppliers and developers.

Tentative Maps and Water Supply Reliability

SB 221 (Kuehl) requires water suppliers, land use planners, and developers to consider water supply at the tentative map stage of the land use planning process. Tentative maps approved for large new subdivisions now must include a requirement that sufficient water supplies will be available to the subdivision, in addition to existing and planned future uses, during normal, single-dry, and multiple-dry years within a 20-year projection. The law will take effect on January 1, 2002. It will apply to tentative maps and development agreements that are approved after that date.

The new law applies to proposed residential subdivisions of more than 500 dwelling units. It also applies to public water systems with fewer than 5,000 existing service connections if the proposed residential development would increase the number of service connections by 10 percent or more.

The heart of SB 221 is a requirement that water suppliers verify that adequate supplies will be available to serve the project. As part of the SB 221 tentative map process, the public water system that will serve the subdivision must provide written verification of its ability to provide sufficient water supplies. Water suppliers that fail to deliver the written verification may be subject to a writ of mandamus suit to compel the water system to comply.

The verification must be supported by substantial evidence, such as the water system’s most recently adopted urban water management plan or water supply assessment. At the very least, the water supplier will have to consider historical information on water supplies, water supply shortage response plans, water use reductions, and the amount of water that the supplier can reasonably rely on receiving from state and federal water projects.

In the verification, the water supplier must also describe the reasonably foreseeable impacts of the proposed subdivision on the availability of water for other uses relying on the same sources of water. Where groundwater is identified as a component of the proposed subdivision’s water supply, the supplier must evaluate whether either it or the landowner has the right to extract the necessary groundwater. If, in providing the verification, the water supplier relies on supplies that are not currently available, it must provide additional written verification that the water rights can be obtained, that the financing for delivery systems is available, and that the permits and regulatory approval will be obtained.

Even if the water supplier is unable to verify sufficient existing or future supplies, that inability may not be fatal to the project. The local agency acting on the tentative map may still approve the tentative map, provided that it finds substantial evidence of additional supplies not accounted for by the public water system.

SB 221 will be codified at Section 11010 of the Business and Professions Code, and Sections 65867.5, 66455.3, and 66473.7 of the Government Code.

Urban Water Management Plans

SB 610 (Costa), SB 672 (Machado), and AB 901 (Daucher) together broaden the requirements for urban water management plans generated by water suppliers to include information on groundwater, supply management, and water quality. SB 610 also limits certain types of funding for suppliers that fail to submit an urban water management plan. These bills take effect on January 1, 2002. Urban water management plans adopted or amended after this date must meet the new requirements.


Under SB 610 and AB 901, urban water management plans that identify groundwater as an existing or planned source available to a supplier must now include detailed information about past and present conditions in the groundwater basin, as well as about the supplier’s planned future pumping.

Supply Management

In addition, SB 610 and AB 901 require that urban water management plans include a description of the supply management projects and programs designed to increase water supply in average, single-dry, and multiple-dry years. Prior law required urban water management plans to discuss only demand management programs in such detail.

SB 672 changes both statewide and local water supply planning requirements. The bill requires the Department of Water Resources to include in the California Water Plan a report on the development of regional and local water supply projects. Projects to be described in the report include local and regional desalinization projects, reclamation efforts, and the construction of dual water systems for new developments. On the local level, the bill requires urban water suppliers to describe water management tools and options that will maximize the use of available resources and minimize the need to import water from other regions

Water Quality

AB 901 requires that, for the first time, urban water management plans include information relating to the water quality of existing sources. Water suppliers must also discuss how the quality affects water management strategies and supply reliability.

Funding Eligibility

SB 610 increases the financial penalties for failing to submit an urban water management plan. Urban water suppliers that do not submit an urban water management plan are now ineligible to receive funding under the Safe, Clean, Reliable Water Supply Act of 1996, the Safe Drinking Water, Clean Water, Watershed Protection, and Flood Protection Act (Costa-Machado Water Act of 2000), or other drought assistance funds. Prior law only restricted certain drought assistance funds to those urban water suppliers.

Water Supply Assessments

SB 610 significantly revises the water supply assessment process for new developments required under the California Environmental Quality Act (“CEQA”). Under this bill, CEQA now requires the responsible public water system to conduct a water supply assessment for any project that would demand at least as much water as a 500 dwelling unit development. The same assessment will also be required for any project that would add 10% or more new service connections for a public water system with fewer than 5,000 existing service connections. Previous CEQA water supply assessment triggers for industrial and commercial projects remain unchanged. Water systems that fail to timely submit an assessment may be subject to a writ of mandamus suit to compel the assessment.

SB 610 will be codified at Section 21151.9 of the Public Resources Code, and Sections 10631, 10656, 10657, 10910, 10911, 10912, and 10915 of the Water Code. SB 672 will be codified at Sections 10013 and 10620 of the Water Code. AB 901 will be codified at Sections 10610.2, 10631, and 10634 of the Water Code.