SB1085 amends CEQA practice in California by forcing cities and counties, at the moment they decide whether an EIR or negative declaration is required (the Section 21080.1 determination), to identify any public water system that could supply a proposed project and to request a formal water supply assessment from those systems. If the system did not already account for the project in its most recent Urban Water Management Plan (UWMP), the assessment must analyze whether total projected supplies will meet the project's demand over a 20‑year horizon under normal, single‑dry, and multiple‑dry year scenarios, alongside other existing and planned uses (including agricultural and industrial uses).
The bill also prescribes the contents of assessments (entitlements and proof, capital outlay programs, permits, regulatory approvals), detailed groundwater disclosure (adjudications, groundwater sustainability plans, past five years’ pumping and projected pumping), and a submission timeline (90 days with a one‑time 30‑day extension requested in a meeting). Lead agencies can seek a writ of mandamus to compel a noncompliant water system.
SB1085 raises upfront scrutiny of water availability for development and reallocates key information‑collection duties to local water systems and planners — with consequences for project timing, small systems’ capacity, and CEQA outcomes.
At a Glance
What It Does
At the time a city or county makes the Section 21080.1 CEQA determination, it must identify any public water system that may supply the project and request a water supply assessment. Assessments must either incorporate UWMP data when the project was already included or provide a 20‑year supply/demand analysis (normal, single dry, multiple dry years) plus documentation of entitlements and groundwater details.
Who It Affects
CEQA lead agencies (cities and counties), public water systems and small water purveyors, developers and project applicants proposing new projects, groundwater sustainability agencies and local agency formation commissions (LAFCOs) consulted when no supplier is identified.
Why It Matters
SB1085 makes water supply analysis a binding, front‑loaded input to CEQA threshold decisions, replacing ad hoc inquiries with standardized assessments. That can clarify water availability earlier but also creates new compliance tasks and potential delay points in the permitting pipeline.
More articles like this one.
A weekly email with all the latest developments on this topic.
What This Bill Actually Does
SB1085 rewrites when and how water availability joins the CEQA conversation. Instead of leaving detailed water analysis to later stages, the bill requires the lead city or county, at the precise moment it decides whether an environmental document is required under Section 21080.1, to identify any public water system that serves or abuts the project site and to request a formal water supply assessment from that system.
If no public water system can be identified, the lead agency must consult local domestic water providers, LAFCO, and any adjacent systems before preparing the assessment itself.
The bill ties assessments to existing planning documents where practical: if the most recent Urban Water Management Plan already accounted for the project’s projected demand, the water system may reuse that information for the assessment. If not, or if the system lacks a UWMP, the assessment must analyze whether projected supplies will meet the project’s demand over a 20‑year horizon under normal, single‑dry, and multiple‑dry year conditions, and must account for other planned and existing uses including agriculture and manufacturing.SB1085 prescribes what evidence must accompany any affirmative supply claim.
Assessments must identify existing entitlements, rights, or contracts and back those claims with written contracts or other proof, copies of capital outlay or financing programs, necessary construction permits, and regulatory approvals. For groundwater sources, the bill requires basin identification, adjudication orders where applicable, groundwater sustainability plans or alternatives for medium/high priority basins, an analysis of basin overdraft status, five years of historical pumped volumes, projected pumping, and an assessment of groundwater sufficiency to meet project demand unless a UWMP has already addressed that question.To keep the CEQA clock moving, the bill sets a 90‑day deadline for a water system to prepare and adopt the assessment after a request, with a one‑time extension of up to 30 days that must be requested in a meeting with the lead agency.
If a system fails to respond, the lead agency may seek a writ of mandamus to compel compliance. SB1085 also allows reuse of an earlier assessment done for a larger project unless there is a substantial increase in water demand, changed circumstances materially affecting supply, or significant new information; hauled water is explicitly excluded as a source for these assessments.
The Five Things You Need to Know
A public water system has 90 days to prepare and approve a water supply assessment after a city or county requests it; it may request one 30‑day extension only by meeting with the lead agency.
If the proposed project was not included in the water supplier’s most recent Urban Water Management Plan, the assessment must project supply and demand over 20 years for normal, single‑dry, and multiple‑dry year scenarios.
Assessments must document existing water entitlements, rights, or service contracts and provide supporting proof such as written contracts, capital outlay programs, construction permits, or regulatory approvals.
When groundwater is a source, the assessment must identify basins, include adjudication orders where relevant, reference groundwater sustainability plans or alternatives, disclose five years of historical pumping and projected pumping, and analyze basin sufficiency.
A prior, compliant assessment for a larger project can be reused for subsequent projects unless water demand rises substantially, conditions change materially, or significant new information emerges; the statute excludes hauled water as a counted source.
Section-by-Section Breakdown
Every bill we cover gets an analysis of its key sections.
Scope—when a city or county must comply
This subsection ties the new requirements to the trigger in Section 21080: if a city or county determines a project is subject to CEQA at the time of the 21080.1 determination, it must follow the water assessment procedures in this part. Practically, that means the obligation arises early in the CEQA timeline and applies only to lead agencies making that determination, not necessarily to every discretionary action.
Identifying potential suppliers and required consultations
Lead agencies must identify any public water system that serves or adjoins the project site and that may supply the project. If no public water system can be identified, the lead agency must consult domestic water providers, the local agency formation commission (LAFCO), and neighboring public water systems before preparing the assessment itself. The provision forces early coordination with local water actors and creates a record tying the water assessment to named suppliers or consultations.
Urban Water Management Plan tie‑in and 20‑year projection requirement
The statute requires lead agencies to request that each identified water system say whether the project’s projected demand was included in its latest UWMP. If it was, the water system may use the UWMP data in the assessment; if not, or if there is no UWMP, the assessment must analyze whether total projected supplies during normal, single‑dry, and multiple‑dry years across a 20‑year projection will meet the project’s demand plus other uses. That mechanism creates a clear default: reuse UWMP where available, otherwise do a forward‑looking 20‑year supply analysis.
Entitlements, proof, and identifying shared sources
These subsections compel assessments to inventory existing water supply entitlements, rights, and service contracts, and to substantiate those claims with documents: written contracts or proof of entitlement, capital outlay or financing plans, construction permits, and any regulatory approvals required to deliver the water. If a system has entitlement documents but has not actually received water under them, the assessment must also identify other systems or contract holders drawing from the same source so the cumulative availability picture is complete. The practical effect is to move claims of available supply from assertion to documentary demonstration.
Groundwater disclosure and analysis
When groundwater is part of the supply mix, the assessment must describe the basin(s), provide adjudication orders and legal pumping entitlements where applicable, and report whether the basin is identified as in overdraft or subject to critical conditions. For adjudicated basins the bill requires the court or board order and the legal pumping amount; for nonadjudicated basins it requires GSPs or approved alternatives for medium/high priority basins and an account of overdraft or projections for low/very low priority basins. The assessment must include five years of historic pumping data and projected pumping, plus an analysis of whether the groundwater will be sufficient to meet the project demand unless a UWMP already covered that analysis.
Timing, adoption, and enforcement
The governing body of each public water system must submit and approve the assessment within 90 days of receiving the lead agency’s request. The system can seek one extension of up to 30 days but must request it in a meeting with the lead agency. If the system misses these deadlines, the lead agency may seek a writ of mandamus to compel compliance — a judicial remedy that shifts enforcement into the courts rather than creating administrative penalties.
Reuse of assessments and triggers for re‑analysis
If a compliant water supply assessment already exists for a larger project, the agency may rely on it for subsequent, related projects unless one of three triggers appears: a substantial increase in project water demand, changed circumstances materially affecting supply, or significant new information that could not have been known when the assessment was prepared. This creates a mechanism to avoid needless duplication while still requiring fresh analysis when the facts change.
Exclusion of hauled water as a source
The statute explicitly states that hauled water does not count as a source in these assessments. That limits reliance on temporary or emergency hauled supplies when certifying long‑term availability for development and prevents hauled water from being used to satisfy the 20‑year sufficiency analysis.
This bill is one of many.
Codify tracks hundreds of bills on Environment across all five countries.
Explore Environment in Codify Search →Who Benefits and Who Bears the Cost
Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- City and county planning departments — they get a structured, document‑based process to evaluate water availability at the CEQA threshold stage, reducing ad hoc queries and producing a record that supports defensible decisions.
- Developers and project applicants who secure positive assessments — when a public water system documents adequate supplies, applicants gain earlier certainty that water will not be a CEQA roadblock, which can speed later permitting and financing.
- Environmental and community groups — the bill standardizes disclosure of entitlements, pumping histories, and groundwater plans, making it easier to evaluate and challenge claims about supply and sustainability.
- Regional water planners and state agencies — standardized, project‑level assessments provide higher‑resolution data about how local projects interact with UWMPs and groundwater sustainability plans, improving regional coordination.
Who Bears the Cost
- Public water systems and small water purveyors — they must prepare technical assessments, assemble legal and engineering supports (contracts, capital programs, permits), and possibly conduct hydrologic and groundwater sufficiency analyses within statutory deadlines.
- Small mutual water companies and very small suppliers — limited staffing and technical capacity make producing the required documentation and five‑year/20‑year analyses disproportionately costly and time‑consuming.
- Cities and counties — lead agencies must identify suppliers, consult LAFCO and other providers when none are obvious, and potentially initiate mandamus litigation to compel noncompliant systems, which consumes staff time and legal budgets.
- Project applicants — if assessments show insufficiency or raise new mitigation obligations, applicants may face project redesign, mitigation costs, or delays in environmental clearance.
Key Issues
The Core Tension
The central dilemma is between the public interest in making CEQA threshold decisions based on documented, forward‑looking water availability and the practical burden of producing that documentation quickly and reliably: higher evidentiary standards reduce guesswork and improve transparency, but they impose technical, legal, and financial costs—especially on small water providers and on projects whose viability hinges on contested or uncertain supplies.
SB1085 trades earlier certainty for heavier up‑front information demands, and that trade causes several practical tensions. Data quality and availability are central: UWMPs are updated on a five‑year cycle and may not reflect up‑to‑the‑minute changes in water rights, infrastructure projects, or supply contracts; groundwater data, particularly in low‑priority basins, can be sparse or inconsistent.
Requiring five years of historical pumping and robust 20‑year projections within a 90‑day window will be straightforward for large, well‑resourced utilities but onerous for small systems that lack hydrogeologists, legal staff, or capital‑planning documents.
The statute’s enforcement technique—a writ of mandamus—avoids creating administrative fines but pushes unresolved disputes into court. That remedies noncompliance piecemeal but risks slow, costly litigation and uneven outcomes across counties.
The bill also raises coordination issues where multiple suppliers or contract holders draw from the same source: the statute requires identifying shared entitlements, but it does not prescribe a single methodology for apportioning available supply, which could invite conflict between systems and between systems and applicants. Excluding hauled water removes a shortcut but could incentivize temporary measures or informal arrangements that the statute disallows, complicating project financing and emergency planning.
Lastly, the bill leans on several external documents (UWMPs, adjudication orders, GSPs) and on local bodies (LAFCOs) to fill information gaps. That cross‑referencing improves integration between water planning and land use but also ties CEQA decisions to the timing, quality, and completeness of other plans that jurisdictions may not control, producing a second‑order dependency that can bottleneck approvals if those underlying plans are outdated or contested.
Try it yourself.
Ask a question in plain English, or pick a topic below. Results in seconds.