California AB 2454: Does a Rental Property Private Well Need Testing?

Usually, no statewide testing mandate applies. California AB 2454 requires the owner of a domestic well serving a rental property to participate only when the well is inside a qualifying free testing-program boundary, and only to the extent that program has capacity. The owner must share program results and interpretation guidance with current residents within 10 days. The owner must provide safe replacement drinking water under the identified program only if program-collected results exceed a primary drinking-water standard, the owner or a resident is eligible, and that program offers replacement water; if it does not, AB 2454 does not require the owner to pay out of pocket.

This page is a homeowner decision aid for AB 2454 as reviewed on August 24, 2026. It is not a legal opinion, a laboratory interpretation, or a substitute for the testing-program administrator, local environmental health agency, or qualified water professional. It answers the state-law question; a county may have separate well, rental, health, or disclosure requirements.

The current California drinking-water code identifies Health and Safety Code section 116688 as added by AB 2454 and effective January 1, 2025.

1. Start with the two coverage gates

AB 2454 is a two-gate rule. Both gates must be open before the statute’s participation workflow applies:

The California Legislature’s enrolled AB 2454 text defines the duty around a domestic well serving a rental property within a testing-program boundary. It also defines a “testing program” narrowly: the service must be free to the owner or a resident, cover at least one primary or secondary drinking-water contaminant, use a laboratory accredited by the state for drinking-water sampling and analysis, and be established by or funded by the State or Regional Water Board.

If the rental is vacant when you check coverage or apply, do not treat the absence of a current resident as closing Gate 1. Confirm with the program what the owner may submit and how it wants occupancy documented. If residents change before results arrive, keep the program record current; the 10-day handoff is addressed separately and applies to the current residents when the owner receives the results.

That means a private test you order on your own may be useful for health and maintenance, but do not assume it is the AB 2454 program test. The statute’s result-sharing duty refers to results received from a testing program. If you have already paid for an unrelated test, send it to the program administrator or local environmental health agency and ask what it does and does not establish.

There is also an important distinction between a private well and a public water system. EPA explains that private domestic-well water is not regulated by the federal Safe Drinking Water Act and that private well owners are responsible for safe household drinking water. AB 2454 is a targeted California requirement for a particular rental-property and program-boundary combination; it does not turn every private well in California into a regulated public water system.

2. Check the live boundary, not just the county name

The State Water Board’s current AB 2454 homeowner guidance and program directory should be your starting point. Select the county, read the program-area description, and then verify the actual parcel or well location with the program administrator. The Board warns that a program may cover an entire county, only a regional water subbasin, or an area that crosses county lines. A county appearing in a directory is not proof that every parcel in that county is covered.

Use this boundary check:

1. Record the property address, parcel number if available, and the well’s location. If the well is on a different parcel from the rental dwelling, record both locations.
2. Open the State Water Board directory and map. Note the program name, administrator, stated geographic area, application link, and date you checked it.
3. Use the program’s own eligibility tool when it has one. If its map is unclear, contact the administrator with the address and coordinates rather than guessing from a county label.
4. Ask whether the program currently has capacity for new testing requests. The statute says participation is required “to the extent that the testing program has capacity.”
5. Ask whether the owner, the resident, or either one can apply; what proof of rental occupancy or well service is needed; which contaminants are included; the recommended repeat interval; and whether replacement drinking water is offered if a result exceeds a primary drinking-water standard.

The Board currently describes multiple programs with different geographic coverage, application processes, eligibility criteria, and services. Some provide testing only; others may offer bottled water, hauled water, refill stations, point-of-use filtration, well maintenance, or a combination. Treat the directory as a live routing tool, not as a permanent statewide list.

If the well appears to sit within more than one program boundary, you do not need to enroll in all of them. Section 116688(b)(2) of the enrolled statute requires participation in only one program at a time. Choose the program that confirms the property is eligible and can accept the request, and save that confirmation.

If you cannot find the well record, that is not a reason to open the well or dismantle the system. A California Department of Water Resources Well Completion Report search may provide construction and location information. DWR notes that records can be missing or spatially limited, so use a report as supporting identification rather than as proof of current program eligibility.

3. Apply, consent, and let the program define the test

Once the two gates are confirmed, the owner’s next action is to contact the eligible program and follow its application process. Do not substitute a generic “well test package” for the program’s scope. The statute gives the owner a specific request duty, subject to capacity:

• Request testing for every primary and secondary drinking-water contaminant the program provides.
• Request a contaminant of emerging concern only if the program offers that option; this is permitted, not a universal requirement.
• Request repeat testing as frequently as the program recommends, again within the program’s capacity.
• Provide the consent the program requires for sampling and for the accredited laboratory to submit results to the State Water Board, a relevant State Board database, the local health officer, or another relevant local agency.

Those requirements are in Health and Safety Code section 116688(b)(1). The practical implication is that the administrator, not a homeowner’s intuition, determines the sampling kit, collection instructions, analyte list, chain of custody, laboratory, and data-sharing path.

Before sampling, make a one-page record of:

For broader private-well care outside this statute, the State Water Board’s GAMA testing guidance recommends regular testing and explains that laboratory analysis supplies concentrations, while a simple presence/absence kit does not provide the same information. GAMA also notes that testing prices vary with the number of constituents and laboratory or outside service used. That general guidance should not be used to invent a required AB 2454 test panel when a qualifying program has supplied its own panel.

4. Treat the 10-day handoff as a documented deadline

The 10-day clock starts when the domestic-well owner receives test results from the testing program. Within 10 days, the owner must ensure that current residents receive both:

1. The test results; and
2. The State Board’s information on how to read and understand those results.

That is the wording of section 116688(d), not merely a recommendation to tell residents that testing occurred. The handoff should be complete enough for a resident to see the report, the units, the tested constituents, any laboratory or program notes, and the interpretation guidance supplied or identified by the Board.

Use this compact deadline checklist:

• Write down the date and time the owner received the program report.
• Calculate the 10-day deadline and set a reminder before it arrives.
• Preserve the original report without editing or cropping result pages.
• Include the State Board interpretation guidance or the program’s direct link to it.
• Deliver the package to every current resident using a method that creates a delivery record.
• Save the report, guidance, delivery date, recipient, and any questions raised.
• Ask the program or local health agency to explain any result that is unclear; do not rewrite a laboratory conclusion yourself.

The statute says “current residents,” so do not assume that sending a report only to a property manager, former tenant, or vacant-unit contact completes the handoff. If occupancy changes during the process, ask the administrator or a qualified housing professional how to document the current-resident list. This page does not infer a special delivery method from the statute; use a reliable method and keep evidence of what was provided and when.

Do not delay sharing while waiting for a treatment quote, a second opinion, or a repair plan. Interpretation and remediation are separate steps. If a result is later corrected or superseded by the program, preserve both versions and share the program’s correction promptly.

5. If a result exceeds a primary standard, branch carefully

An exceedance is a health and program question, not an invitation to improvise a filter. The State Water Board’s GAMA guidance says that if a result is above a primary maximum contaminant level, it is recommended that people not consume the water until appropriate action is taken. It also cautions that the appropriate response can depend on the contaminant and advises contacting the local Environmental Health Department about making the water safe.

For an AB 2454 program result, follow this sequence:

1. Share the result and interpretation guidance within the 10-day window even if the result is difficult to interpret.
2. Contact the testing-program administrator immediately and ask which result, standard, and eligibility rule controls the program response.
3. Confirm whether the result exceeds a primary drinking-water standard, as opposed to a secondary standard or a general aesthetic guideline. Do not treat every taste, odor, or secondary-standard issue as the same statutory branch.
4. Confirm whether the owner or a resident is eligible for the program’s safe-drinking-water service.
5. Confirm that the program actually offers free replacement drinking water and what form it takes: for example, bottled water, hauled water, a refill station, or another program-defined option.
6. Follow the program’s instructions for obtaining and maintaining that replacement supply while the water-quality issue is evaluated.

The State Water Board’s AB 2454 FAQ makes the conditional nature explicit: not all programs provide free replacement water, and some provide it only for a specified contaminant or only when eligibility conditions are met. The Board also states that if the testing program does not provide free replacement water, AB 2454 does not require the owner to pay out of pocket for replacement water under this statute.

The statutory safe-water duty has three linked conditions: the program-collected result demonstrates an exceedance of any primary drinking-water standard; the owner or a resident is eligible for safe drinking water under an identified program; and the owner provides safe drinking water under that program. That is why “the test is high” and “the program will supply bottles” are not interchangeable conclusions.

Until the program or health authority gives contaminant-specific direction, do not assume boiling solves the problem. The State Water Board’s private-well owner guide explains that boiling does not remove many commonly found toxic constituents. Use a confirmed safe source for drinking and cooking when advised, and ask the local health agency about any limits on bathing or other uses.

6. Keep costs, rent, and program limits separate

AB 2454 prohibits the owner from imposing a charge or increasing a fee, rent, or other charge on a resident solely as a result of the statute’s requirements. This is a direct statutory cost rule in section 116688(f). It is not a license to relabel testing, result sharing, or required safe-water service as a new tenant fee.

The phrase “solely as a result” matters. This page does not decide every rent, utility, lease, deposit, or habitability question, and it does not say that every charge in a rental relationship is governed by AB 2454. It does mean that the owner should not create a new water-testing or safe-water charge, or increase rent for that reason, as a way to shift these statutory duties to the resident. Get California landlord-tenant advice before making any related lease or billing change.

Program capacity also matters. The statute requires participation to the extent the program has capacity, and it says the section imposes no new obligation on a testing program. If the administrator says the program is full, paused, outside its service area, or unable to provide a particular service, save that response and ask what the correct next step is. Do not promise residents a testing date or replacement-water service that the program has not confirmed.

7. Know what not to infer, and what to hand a professional

These conclusions are safe to make from the evidence:

• A California private well is not automatically covered by AB 2454 just because it serves a rental.
• A property is not automatically covered just because its county appears in the directory.
• A qualifying program’s free test is not necessarily the same as a homeowner’s private lab package.
• An overlapping boundary does not require enrollment in multiple programs at once.
• A result exceedance does not, by itself, prove that the program will supply replacement water.
• A safe-water program response does not identify the correct treatment system, repair, or permanent source without professional and program-specific evaluation.

For anything beyond the program’s sampling instructions, use qualified help. A water-quality professional or local Environmental Health Department can help interpret a contaminant-specific result. A licensed well or pump professional can inspect the physical system and advise on repair or treatment. Bring the program confirmation, property and well location, original laboratory report, interpretation guidance, dates, prior results, treatment records, and a list of any recent flooding, construction, pump work, land-use change, taste, odor, or color change.

For general private-well safety, EPA recommends testing at least annually for several common indicators and testing promptly after flooding, significant nearby changes, repairs, or a change in water quality. Those are sensible health-protection triggers, but they do not replace the live AB 2454 boundary and program-capacity check.

Do not open an energized control box, test live wiring, open the well casing, pull a pump, enter a confined space, or manipulate pressurized equipment to answer this legal or water-quality question. Those actions can expose you to shock, stored pressure, falls, contamination, or equipment damage. Leave them to qualified professionals. A homeowner can safely gather documents, check the State Water Board directory, contact the program, record dates, and deliver the report; the hazardous physical work is not part of the AB 2454 decision.

The practical endpoint is a dated file: the property and well location, the program and boundary confirmation, the capacity and eligibility response, consent and sampling instructions, the original result, the 10-day resident handoff, and any safe-water or professional guidance. If those records show both coverage gates are open, follow the program’s test and repeat schedule. If either gate is closed, do not describe AB 2454 as a statewide testing mandate—but keep monitoring the live directory and follow ordinary private-well health practices.