Groundwater Rights California Explained

California's groundwater rights are complex and have undergone significant changes in recent years. If you own property with a well or are considering drilling one, understanding your rights and responsibilities is essential. Here's what Southern California well owners need to know about groundwater law, SGMA regulations, and your rights to pump water from your well.

The Basics: Do You Own the Groundwater Under Your Land?

Short answer: You have rights to USE groundwater under your property, but you don't "own" it.

Groundwater rights in California are based on correlative rights (for overlying landowners) and appropriative rights (for those transporting water off the property). This differs from surface water, which is strictly regulated by the state.

Types of Groundwater Rights

1. Overlying Rights (Most Common for Homeowners)

If you own land above a groundwater basin, you have overlying rights to pump groundwater for reasonable and beneficial use ON that property.

• What it means: You can pump water for household use, livestock, irrigation of your property, and other reasonable on-site uses
• Priority: Overlying rights take priority over appropriative rights
• Limitations: Use must be "reasonable and beneficial" – you can't waste water or use it in ways that unreasonably harm neighbors
• No permit required (usually): Domestic wells typically don't require state water rights permits

2. Appropriative Rights

If you want to pump groundwater and transport it OFF your property for use elsewhere, you need appropriative rights.

• What it means: Selling water, transporting to another property, commercial bottling, etc.
• Lower priority: Junior to overlying rights
• Requires permit: You must apply to the State Water Resources Control Board
• Less common: Most private well owners don't need this

3. Prescriptive Rights

In rare cases, someone can gain rights through continuous, open use of groundwater over a long period (similar to adverse possession of land). This is complex and requires legal proceedings.

SGMA: The Game Changer

The Sustainable Groundwater Management Act (SGMA), passed in 2014 and implemented over the following years, fundamentally changed California groundwater management.

What SGMA Does

• Requires local agencies to manage groundwater basins sustainably
• Sets goals to prevent chronic lowering of water tables
• Gives Groundwater Sustainability Agencies (GSAs) power to regulate pumping
• Mandates groundwater sustainability plans (GSPs)
• Allows fees and restrictions on pumping

Does SGMA Affect Your Well?

It depends on which groundwater basin you're in.

Check Your Basin Status

Visit the California Department of Water Resources (DWR) SGMA Basin Prioritization website to see if your property is in a managed basin. You can search by address or parcel number.

Reasonable Use Doctrine

Even with overlying rights, California law requires "reasonable and beneficial use" of water. This is enshrined in the state constitution.

What Is Considered Reasonable?

• Household water use (drinking, cooking, bathing, laundry)
• Watering a reasonably-sized landscape
• Filling a swimming pool
• Watering livestock
• Irrigating crops on your property

What Might Be Unreasonable?

• Excessive waste (running water continuously into a ditch)
• Pumping in a way that causes neighbor's wells to go dry (if avoidable)
• Using significantly more water than similar properties in the area

"Reasonableness" is fact-specific and can be subject to legal interpretation if disputes arise.

When Can Your Groundwater Rights Be Limited?

1. SGMA Management

In high/medium priority basins, GSAs can:

• Require meters and usage reporting
• Impose extraction fees
• Limit pumping during critical overdraft
• Allocate pumping rights

2. Adjudicated Basins

Some groundwater basins have been "adjudicated" through court proceedings, assigning specific pumping rights to users. Once adjudicated:

• Each user has a defined allocation
• A watermaster oversees compliance
• Pumping beyond your allocation may require purchasing rights from others
• Rare in rural areas, more common in developed basins (e.g., some Orange County and LA County basins)

3. Emergency Drought Regulations

During severe droughts, the state can impose emergency regulations on groundwater use, though historically these have focused more on municipal suppliers than individual domestic wells.

4. Local Ordinances

Some counties have groundwater management ordinances that require:

• Well registration
• Annual reporting (in certain basins)
• Metering of large users

Well Permits vs. Water Rights

Southern California Specific Considerations

San Diego County

Most rural San Diego County groundwater basins are low-priority under SGMA and not subject to intensive management. Traditional overlying rights apply.

• Well permits required through County Environmental Health
• No metering or reporting required for domestic wells (as of 2026)
• Some areas near the coast have saltwater intrusion concerns

Riverside County

More complex due to several SGMA-designated basins:

• Some basins are medium or high priority (Coachella Valley, parts of Western Riverside)
• GSAs formed in several basins – requirements vary
• Domestic wells may be exempt from certain restrictions but not all
• Check with local GSA for your specific area

San Bernardino County

Large county with diverse groundwater situations:

• Some heavily-managed basins (e.g., parts of Mojave Desert)
• Other areas with minimal regulation
• Varies significantly by location

Neighbor Disputes Over Groundwater

What happens if your pumping affects a neighbor's well (or vice versa)?

• Correlative rights: In times of shortage, overlying users share the available water proportionally to their land size and reasonable needs
• Cannot be deliberately wasteful: If you're wasting water and causing a neighbor's well to decline, you could be liable
• No absolute protection: However, reasonable use on your property that incidentally affects a neighbor is generally not actionable
• Legal remedies: Disputes may require civil litigation to resolve

Practical Advice for Well Owners

Protect Your Rights

• Keep all well permits and construction records
• Document the date your well was drilled (priority can matter)
• Maintain records of reasonable, beneficial use
• If your well predates SGMA (2014), document this

Stay Informed

• Check if you're in a SGMA-managed basin
• If so, monitor your GSA's activities and proposed regulations
• Attend public meetings if new rules are being considered
• Join local water associations if available

Use Water Responsibly

• Fix leaks promptly
• Use efficient irrigation (drip systems)
• Don't waste water – it protects your legal standing and the aquifer

The Future of California Groundwater Rights

SGMA is still being implemented and will continue to evolve. Expect increasing scrutiny of groundwater use in overdrafted basins. For most rural well owners in low-priority basins, traditional rights will likely continue. However, staying informed is essential as regulations develop.

Questions About Your Well Rights?

While Southern California Well Service focuses on well construction and maintenance rather than legal water rights, we're familiar with the regulatory landscape and can point you in the right direction. For legal questions about water rights, consult a water law attorney.

For well construction, repairs, and maintenance throughout San Diego, Riverside, and San Bernardino counties, call us at (760) 440-8520. CSLB license #1086994.