If you own or plan to drill a water well in California, the law you have to navigate is a mix of state construction standards, county permitting, and — since 2014 — local groundwater rules written under the Sustainable Groundwater Management Act. California water well law now touches nearly every stage of a well’s life: where you can drill, how deep, how the well is built, how much you can pump, what you report, what you pay, and how you retire the well when you are done with it. What applies to you depends heavily on where your property sits.
Who Regulates Your Well
California’s groundwater framework rests on the Sustainable Groundwater Management Act (SGMA), signed in 2014.1Department of Water Resources. Sustainable Groundwater Management Act SGMA does not set one statewide pumping cap. Instead, it requires every high- and medium-priority groundwater basin to reach sustainability, and it pushes the day-to-day rulemaking down to local Groundwater Sustainability Agencies (GSAs).2California State Water Resources Control Board. What Is the Sustainable Groundwater Management Act Critically overdrafted basins must hit sustainability by 2040; other high- and medium-priority basins have until 2042.
Each GSA writes a Groundwater Sustainability Plan (GSP) for its basin. Under Water Code section 10726.4, a GSA can require well registration, impose spacing rules, cap or suspend pumping, set extraction allocations, and levy fees.3California Legislative Information. California Water Code 10726.4 GSAs do not issue the well permit itself; counties still do that. But a GSA can require the county to route permit applications through it for review before approval.
Because every plan is local, spacing rules, extraction caps, and fees vary from basin to basin. The practical first step for any well owner is identifying the GSA that covers the property and pulling up the current GSP. The Department of Water Resources maintains a basin map and GSA directory.
Drilling a New Well
Building a new well starts with a permit application to the local enforcing agency, usually the county Department of Environmental Health. The application asks for the well’s intended use, proposed depth, GPS coordinates, and a site map showing distances from potential contamination sources such as septic systems, sewer lines, and animal enclosures.
The drilling itself has to be done by a contractor holding a C-57 Well Drilling classification from the Contractors State License Board.4CSLB. C-57 – Well Drilling Contractor Construction must meet the minimum statewide standards in Department of Water Resources Bulletins 74-81 and 74-90, which cover casing materials, sealing methods, and separation distances.5California Department of Water Resources. Well Standards
Setback Distances
Bulletin 74-90 sets the minimum horizontal distances from known contamination sources. Local agencies can go stricter, but not looser:
- Sewer lines: 50 feet
- Septic tanks and leaching fields: 100 feet
- Cesspools and seepage pits: 150 feet
- Animal enclosures: 100 feet
- Recycled water use areas: 50 to 150 feet, depending on treatment level
Those figures assume the well is drilled through unconsolidated material less permeable than sand. Wells in fractured rock formations need significantly greater separation. Wells serving a public water system also require a 50-foot control zone around the wellhead, secured through ownership or easement.6California State Water Resources Control Board. Requirements for New Wells
After the Well Is Drilled
Within 60 days of finishing construction, the driller has to file a Well Completion Report with the Department of Water Resources. The report includes the well log, construction details, perforation information, and the methods used to seal off surface water and prevent cross-contamination between aquifers.7California Legislative Information. California Water Code 13751 Before putting the well into service, the owner is responsible for water quality testing, particularly for bacterial contamination. The local agency reviews the results and inspects the work.
When New Wells Get Blocked
In basins already pumped past their limits, getting a new permit is harder. In critically overdrafted basins, the county cannot issue a well permit until it obtains written verification from the GSA that the proposed well is consistent with the basin’s sustainability plan.1Department of Water Resources. Sustainable Groundwater Management Act If the GSA determines the additional pumping would undermine sustainability or interfere with nearby wells, the application does not move forward.
Counties and the State Water Resources Control Board can also impose temporary moratoria on new drilling during severe drought. These freezes have been used repeatedly and can last months or longer.
A separate risk is basin probation. If a GSA fails to adopt or implement an adequate plan, the State Water Board can designate the basin as probationary and step in directly, mandating extraction reporting, metering, and possibly an interim plan that overrides the GSA. Probation also brings higher per-acre-foot fees.8California State Water Resources Control Board. SGMA Reporting and Fees
Reporting and Fees for Existing Wells
Owners who pump groundwater in a high- or medium-priority basin that either lacks a GSA (an “unmanaged area”) or has been placed on probation must file an annual groundwater extraction report with the State Water Board. Reports go through the GEARS online portal and are due by February 1, covering the previous water year (October 1 through September 30).8California State Water Resources Control Board. SGMA Reporting and Fees Each report identifies the well owner and location, the well’s capacity, monthly extraction volumes, and where and how the water is used. Volumes must be measured by a method the Water Board considers satisfactory.
Annual extraction fees come with the report:
- Unmanaged areas, metered: $10 per acre-foot
- Unmanaged areas, unmetered: $25 per acre-foot
- Probationary basins: $20 per acre-foot
- Probationary basins with an interim plan: $35 per acre-foot
Basins where the Water Board determines probationary deficiencies remain unresolved face an added $15 per acre-foot surcharge on top of the probationary rate.9California State Water Resources Control Board. Sustainable Groundwater Management Act (SGMA) The gap between metered and unmetered rates in unmanaged areas is a direct incentive to install a meter.
Any significant modification to an existing well, including deepening, reconstruction, or major repair, requires a new or modified permit from the local enforcing agency and triggers a review similar to a new well application.
The De Minimis Exemption
If you pump no more than two acre-feet per year (roughly 650,000 gallons) for domestic household use only, you qualify as a de minimis extractor and are exempt from state extraction reporting and fees.10California State Water Resources Control Board. Groundwater Extraction Reporting Requirements Under SGMA Most single-family homes with a well are comfortably below the threshold. Even so, notify the State Water Board through GEARS so the agency records that you qualify; otherwise you may keep getting compliance notices. And the exemption is only from state-level reporting. Your local GSA can still require registration, metering, or fees under its own plan.
Keeping or Retiring an Unused Well
An unused well is not a neutral thing to have on your property. California treats a well as abandoned once it has gone a year without use, unless the owner shows intent to use it again by keeping it properly maintained.11California Department of Water Resources. Part III – Destruction of Water Wells An improperly abandoned well is a direct conduit for surface contamination to reach the aquifer.
To keep an inactive well compliant, the owner has to make sure it does not impair water quality, keep the top secured with a locked or fastened cap, mark and label the well visibly, and keep the surrounding area clear of debris. After five consecutive years of inactivity, the cover must be watertight.
Any abandoned well must be destroyed by filling it completely with approved sealing materials from the bottom up. Before destruction, the well has to be investigated for its condition and any obstructions. If contamination is found or suspected, notify the local enforcing agency before proceeding. Destruction work also triggers a Well Completion Report filing within 60 days.7California Legislative Information. California Water Code 13751 Professional destruction typically runs between $1,500 and $5,000 depending on the well’s depth and condition.
Water Quality Is Your Responsibility
Testing is required to get a new well approved, but the responsibility does not end at hookup. Unlike public systems, private wells are not monitored by any agency after construction. The EPA recommends testing your well every year for total coliform bacteria, nitrates, total dissolved solids, and pH, and comparing the results against the national Maximum Contaminant Levels.12US EPA. Protect Your Home’s Water Test sooner if you notice a change in taste, color, or odor, or after flooding, nearby construction, or agricultural activity. County environmental health can point you to certified labs and advise which tests to request based on local conditions.
What Non-Compliance Costs
Missing the February 1 report brings a 25 percent surcharge on the annual extraction fee, plus another 25 percent for every 30 days the report stays unfiled, capped at three times the annual fee.9California State Water Resources Control Board. Sustainable Groundwater Management Act (SGMA) If you never file, the State Water Board can investigate your extraction activity at your expense and determine what should have been reported, after giving 60 days’ notice and a chance to file. Filing a false report or tampering with a measuring device can bring misdemeanor charges. Local GSAs can add their own penalties on top, which vary by basin.