Water Rights California Wells

California's groundwater law is complex and evolving, especially since SGMA. Understanding your rights—and their limits—helps you make informed decisions about drilling, pumping, and protecting your water supply.

Types of Groundwater Rights

Overlying Rights

As a landowner, you have "overlying rights" to reasonable use of groundwater beneath your property for use on that property. This is the most basic groundwater right.

• Comes with land ownership automatically
• Limited to use on the overlying land
• Must be for "beneficial use"
• Subject to correlative sharing in shortages

Correlative Rights

The principle that all overlying landowners share rights to the groundwater beneath their properties:

• Equal right to reasonable use
• During shortage, must share proportionally
• No "first in time, first in right" (unlike surface water)
• Based on beneficial use, not pumping capacity

Appropriative Rights

Rights to pump groundwater for use off the overlying land (export):

• Secondary to overlying rights
• May require permit or allocation
• Can be limited during shortages
• Subject to SGMA restrictions

How SGMA Affects Water Rights

The Sustainable Groundwater Management Act (SGMA), passed in 2014 and implemented starting in 2020, fundamentally changed California groundwater law. For the first time in state history, groundwater extraction can be regulated by local Groundwater Sustainability Agencies (GSAs) even for overlying landowners who historically had near-absolute rights to pump reasonable amounts of water beneath their land.

SGMA applies to basins designated as high- or medium-priority. If you own a well in a SGMA-regulated basin, here's what can happen to your traditional overlying rights:

Extraction Limits and Allocations

GSAs have the authority to set individual pumping allocations to achieve sustainable groundwater management. This means your GSA can tell you exactly how much water you're allowed to pump in a given year, even if you have historical overlying rights and even if you're only using the water on your own land for beneficial purposes. These allocations are typically based on:

• Land use: Residential, agricultural, commercial, or industrial
• Historical pumping: What you've pumped in past years (which is why some landowners rushed to establish pumping history before allocations were set)
• Acreage or parcel size: Larger properties may receive larger allocations
• Water duty factors: Estimated reasonable water needs for your land use type

If your allocation is less than you actually need, your options are limited: reduce use, buy or lease allocation from another user (if the GSA allows transfers), or seek a variance based on specific circumstances. The GSA has broad authority to manage the basin, and challenging allocations in court is expensive and uncertain.

Extraction Fees and Charges

Many GSAs are implementing per-acre-foot extraction fees to fund operations and incentivize conservation. These fees vary widely:

• Some basins charge $50-200 per acre-foot
• Others use tiered pricing (higher rates for pumping above your allocation)
• De minimis users (typically residential wells pumping less than 2 acre-feet/year) are often exempt, but not always
• Fees can increase over time as GSAs develop and implement more aggressive management strategies

For context, a typical single-family household uses 0.5 to 1.0 acre-feet per year. A small farm or horse property might use 5-20 acre-feet depending on irrigation needs and acreage.

New Well Restrictions

Some SGMA basins have enacted moratoria on new wells or require GSA approval before drilling. Even in basins without explicit prohibitions, new wells may face:

• Limited or zero pumping allocation
• Requirements to offset pumping by retiring other water rights or implementing recharge projects
• Restrictions on depth (to avoid impacting existing wells)
• Mandatory metering and reporting from day one

If you're planning to drill a new well in San Diego County, check whether your property is in a SGMA-regulated basin and what the current GSA rules are before committing to the drilling expense.

Metering and Reporting Requirements

Many GSAs now require wells to be metered and pumping data reported monthly, quarterly, or annually. This applies even to domestic wells in some basins, though de minimis users are often exempt. Failing to comply with metering and reporting requirements can result in fines, reduced allocations, or legal action by the GSA.

San Diego County SGMA Basins

Not all of San Diego County is subject to SGMA regulation. The county has relatively few high- or medium-priority basins compared to the Central Valley. Key SGMA basins in the region include:

• Warner Valley Basin: Covers parts of Warner Springs and the upper San Luis Rey River watershed
• Borrego Valley Basin: Critically over-drafted, with aggressive management and pumping reductions required
• Pauma Valley Basin: Medium-priority, developing Groundwater Sustainability Plan

Most of the backcountry well-dependent areas in San Diego County (Ramona, Julian, Alpine, Lakeside, Valley Center, Fallbrook) are not in SGMA-regulated basins as of 2026, meaning traditional overlying rights still largely govern groundwater use. However, this could change if basins are reclassified in future DWR updates.

Adjudicated Basins

Some California groundwater basins have been adjudicated through court proceedings that definitively establish water rights for all users in the basin. Adjudication typically happens when competing water users cannot agree on voluntary management and file lawsuits to resolve disputes over pumping rights.

In an adjudicated basin:

• Court-determined allocations: Each water right holder receives a specific annual pumping allocation (often measured in acre-feet per year) based on historical use, land ownership, and beneficial use. These allocations are legally binding and enforceable.
• Watermaster administration: A court-appointed watermaster monitors pumping, enforces allocations, manages carryover and transfers, and reports to the court. The watermaster has legal authority to enforce compliance.
• New pumpers face high barriers: If you buy property in an adjudicated basin and want to drill a new well, you typically cannot pump unless you acquire existing water rights from another user. Rights are bought and sold like any other property interest, and prices can be substantial ($5,000-20,000+ per acre-foot of annual allocation depending on the basin).
• Exempt from SGMA: Adjudicated basins are considered already sustainably managed and are exempt from SGMA requirements. This means no GSA governance, but also no opportunity to influence management—the court order governs.

San Diego County Adjudicated Basins

San Diego County has very few adjudicated groundwater basins compared to other parts of California. Most well owners in the region are not subject to adjudication. However, if you're buying property with a well, it's worth confirming that the property is not in an adjudicated basin and that you're not acquiring a property with zero or limited water rights.

Key questions to ask when buying well-dependent property:

• Is the property in a SGMA-regulated basin, and if so, what is the current pumping allocation?
• Is the property in an adjudicated basin, and what water rights (if any) convey with the sale?
• Are there any outstanding water rights disputes or pending litigation affecting the basin?
• Has the seller been compliant with all metering and reporting requirements?

These are legal questions best addressed with a water rights attorney during escrow. Do not assume that because a property has a well, you have unlimited rights to pump water from it.

Domestic Use Protection

Domestic well use—water for household purposes like drinking, cooking, bathing, and landscape irrigation for a single-family residence—generally receives some protection under California water law, but this protection is neither absolute nor uniform across all basins.

De Minimis Extractors Under SGMA

SGMA defines "de minimis extractors" as groundwater users who pump 2 acre-feet per year or less for domestic purposes. This is roughly equivalent to a typical single-family household's annual water use. De minimis extractors receive some statutory protections:

• GSAs are not required to regulate de minimis users (though they can choose to)
• Many GSAs exempt de minimis domestic wells from metering and reporting requirements
• Some GSAs exempt de minimis users from extraction fees
• However, during severe shortages or basin overdraft conditions, even de minimis users may face restrictions

The 2 acre-foot threshold is important. If your household uses more than 2 acre-feet per year—which can happen with large landscaping, a pool that requires frequent refilling, or if you're irrigating a small hobby farm or pasture—you may not qualify for de minimis status and could face fuller regulation.

Beneficial Use Doctrine

California's constitutional mandate is that all water use must be "reasonable and beneficial." Domestic use for household needs is universally recognized as beneficial use and is given priority in both statute and case law. Courts have consistently held that domestic water needs are fundamental and should be protected.

However, "domestic use" does not mean unlimited use. Wasting water—letting sprinklers run excessively, not fixing leaks, watering ornamental landscaping during drought restrictions—can be deemed unreasonable use even for domestic purposes. And domestic use does not automatically trump all other uses; it must still be reasonable in the context of basin conditions and availability.

What Happens During Severe Shortages?

In critically over-drafted basins or during severe droughts, even domestic wells may face restrictions:

• Outdoor irrigation bans: You may be prohibited from watering lawns, washing cars, or filling pools
• Allocation reductions: Even de minimis users could see their allowed pumping reduced below 2 acre-feet
• Emergency ordinances: Counties or GSAs can impose temporary pumping limits during declared water emergencies
• Well interference: If neighboring wells go dry due to over-pumping, the affected parties may have legal recourse even against domestic users

The Borrego Springs area is an example of how severe over-drafting can affect domestic wells. The Borrego Valley Groundwater Basin is critically over-drafted, and the local GSA has implemented aggressive pumping reductions. While domestic users initially received some protection, the severity of the situation means everyone—including households—must reduce use to achieve sustainability.

Practical Guidance for Domestic Well Owners

If you own or are considering buying property with a domestic well:

• Know your basin status: Find out if you're in a SGMA-regulated basin, an adjudicated basin, or neither
• Stay under 2 acre-feet if possible: This keeps you in de minimis status and minimizes regulatory burdens
• Install water-efficient fixtures and landscaping: Drought-tolerant landscaping and low-flow fixtures reduce use and demonstrate reasonable use
• Fix leaks promptly: Besides saving water, it shows you're not wasting a precious resource
• Keep records: If your GSA requires reporting, keep accurate logs. If not, keeping voluntary records of well maintenance and pumping (if metered) can be useful if disputes arise
• Understand your well's capacity: Know your well's sustainable yield and don't over-pump. Over-pumping your own well can damage it and potentially affect neighbors, creating liability

We service all major pump brands including Franklin Electric, Grundfos, Goulds (Xylem), and Sta-Rite (Pentair). Our trucks carry common parts and components for same-day repairs.

Frequently Asked Questions