Can I pump as much water as I want from my well?

Historically, overlying landowners could pump reasonable amounts for beneficial use on their property. However, SGMA has changed this in regulated basins, where GSAs can now limit extraction. In adjudicated basins, court-determined allocations govern pumping. Even in unregulated areas, you must not unreasonably harm neighbors' wells or the aquifer. Domestic use for household needs is generally protected, but large-scale agricultural or commercial pumping may face restrictions.

What are correlative rights?

Correlative rights is the California legal doctrine for groundwater. It means all overlying landowners have equal rights to reasonable use of groundwater beneath their properties. In times of shortage, users must share the available supply proportionally rather than 'first in time, first in right' (which applies to surface water). This differs from some other states' groundwater rules.

Can my neighbor's well affect my water rights?

Yes. If your neighbor's pumping lowers the water table and affects your well, you may have legal recourse, but the situation is complex. Under correlative rights, both parties are entitled to reasonable use. If a neighbor pumps unreasonably (wasting water, pumping for non-beneficial use, or for export off the land), you may have grounds for action. However, simply pumping for reasonable use on their land is generally protected, even if it affects your well.

Water Rights California Wells: Understanding Groundwater Law

Q: Do I own the groundwater under my property?

In California, you don't 'own' groundwater in the traditional sense, but you have 'overlying rights' to reasonable use of groundwater beneath your land for use on that land. This is different from owning mineral rights or the water itself. Your rights are correlative with other overlying users—during shortages, all users must share proportionally. These rights can be modified by SGMA regulations, adjudicated basin rules, or prescriptive rights established by others.

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.

Disclaimer

This is general information, not legal advice. Water rights issues can be complex and fact-specific. Consult a water rights attorney for specific situations.

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

SGMA fundamentally changed groundwater rights in California:

GSAs can limit pumping: Even overlying users may face extraction limits
Allocations possible: Basins may establish individual pumping allocations
Fees authorized: GSAs can charge for groundwater extraction
New wells restricted: Some basins limit or prohibit new wells
Metering required: Some GSAs require monitoring production

Adjudicated Basins

Some California groundwater basins have been adjudicated—courts have determined water rights for all users:

Court establishes individual allocations
Watermaster administers the basin
New pumpers must acquire rights from existing users
Exempt from SGMA (already managed)

Domestic Use Protection

Domestic well use generally receives some protection:

SGMA recognizes "de minimis" users (<2 acre-feet/year)
Domestic use is considered beneficial use
Courts have recognized residential water needs
However, protection isn't absolute—severe shortages may affect all users

Frequently Asked Questions

Do I own the groundwater under my property?

You don't "own" groundwater, but you have overlying rights to reasonable use. These rights are correlative with other overlying users and can be modified by SGMA regulations.

Can I pump as much as I want?

Historically, overlying landowners could pump reasonable amounts. SGMA changed this—GSAs can now limit extraction in regulated basins. Domestic use is generally protected.

Can my neighbor's pumping affect my rights?

If their pumping is unreasonable (wasting water, pumping for export), you may have recourse. Reasonable use for their property is generally protected even if it affects your well.

Questions About Your Water Rights?

We can help you understand how regulations affect your well project. For legal rights questions, consult a water rights attorney.

Call (760) 463-0493

Water Rights California Wells