Tap Water Quality in San Diego

Not everyone in the San Diego area gets water from the City. The City's 2020 Urban Water Management Plan says about 50,000 people who live inside the City limits are served by other water agencies. Elsewhere in the county, separate public water systems serve their own areas; the State Water Board's Drinking Water Watch lists, among others, Sweetwater Authority, Otay Water District, Helix Water District and Padre Dam Municipal Water District. The City's plan says California American Water serves Coronado and Imperial Beach, using water the City sells it.

A quick summary of the causes the City lists in its water quality FAQ. Details follow below.

• Brown, orange or yellow. The City explains that sediment naturally settles along the bottom of water pipes, and that work on a pipeline in the street, or a disturbance in your own plumbing such as a broken water softener, can stir it back up. After street work, it suggests waiting 24 hours after the work ends so the sediment can settle, then opening all your faucets and outdoor hose bibs until the water runs clear, which can take up to 15 minutes. If the indoor taps are discolored but the outdoor hose bibs run clear, the City says the problem may be your interior piping or water softener, and a plumber or softener service is the next call. If it does not clear after flushing, call the Water Quality Hotline, 619-668-3232, which can also explain how to flush.
• Cloudy, milky or white. The City says this is almost always tiny air bubbles. Air can come out of the water when it moves from the pressurized mains into the lower pressure of your home, can be trapped in the lines after the water is shut off for repairs, and is released more easily when the water warms up in hot weather. It is usually short-lived. If it lasts more than 24 hours, call 619-668-3232.
• Black specks or particles. The City says these usually come from rubber gaskets breaking down in a building's plumbing or water softener over time, and suggests having a plumber look first. If they keep appearing, call 619-668-3232.
• Water softeners. The City's FAQ says its water is already balanced and does not need softening, and that softeners remove natural minerals, which can make water more corrosive to plumbing.

After a main break or shutoff, our water leaks and main breaks guide covers what crews do and the City's advice on running faucets and cleaning aerators once the water is back on.

• Chlorine. The City keeps a disinfectant in the water all the way through the pipes so bacteria cannot grow, so some customers notice a slight chlorine smell. Its 2025 water quality report says the City uses chloramines, made by adding chlorine and ammonia, for this; in 2025 the distribution system average was 1.75 ppm, below the maximum residual disinfectant level of 4.0 ppm. The City's FAQ says the level is safe for people and pets to drink, but that chlorine and chloramine are harmful to fish, so ask a fish-care expert how to treat aquarium and pond water.
• Earthy or musty. The City says natural algae blooms in its reservoirs can produce geosmin, which has an earthy smell and taste; blooms can happen any time but are more common in warm summer months, and some people notice tiny amounts more than others. The City says geosmin is not a health risk and that a carbon filter attached to the faucet can reduce the taste.
• Foul or rotten-egg smell at the sink. The City says bacteria growing on soap and food buildup in a drain can give off gases you smell when you turn on the tap, and that pouring a cup of bleach down the drain and letting it sit for an hour often helps. If odors persist, call 619-668-3232. A smell from a floor drain, a toilet or outdoors may be a sewer problem instead; see our sewer spills and odors guide.
• Taste and odor standards. The EPA's secondary drinking water standards cover nuisance qualities such as taste, color and odor. The EPA describes them as "non-mandatory water quality standards" and lists noticeable effects such as a "rotten-egg", musty or chemical smell for odor, and a "rusty color; sediment; metallic taste" for iron.

• Call 619-515-3525 for a pressure check. The City's meter and water pressure page says a Public Utilities crew member will test the pressure at the fire hydrant nearest your home and report back, and that normal pressure varies by about 10 psi either way. Causes it lists include a failed pressure regulator on your property, neighbors on a shared meter using more water, temporary pipes during main replacement, and leaks.

Our water leaks and main breaks guide covers pressure, regulators and no-water situations in full.

A notice comes from your water provider. One example: after a contractor broke a water main in Encanto, the City issued a precautionary boil water notice for parts of Encanto, Emerald Hills, Jamacha and Broadway Heights. Its notice page says the notice was lifted two days later, after testing and monitoring found no contamination, in coordination with the State Water Resources Control Board and the County Department of Environmental Health.

The CDC's overview of drinking water advisories explains the three kinds:

More from the same CDC page:

• "Boil your tap water even if you filter it."
• During any drinking water advisory, "do not drink or use water from appliances connected to your water line. This includes the water and ice dispensers in your refrigerator or freezer."
• "In many cases, you can use tap water and soap to wash your hands during a boil water advisory." When bathing, "Be careful not to swallow any water."
• For infants, "provide ready-to-use formula if possible." For pets, "Give pets commercially bottled water or boiled water that has cooled."

Always follow the specific instructions in the notice, including when it is lifted. For a City notice, the City's Public Utilities pages and the numbers in this guide are the place to check.

• Service lines. The City's service line inventory page says it outlawed lead pipes in its water system in 1927, decades before the federal ban in 1986, and that a 2010 to 2020 survey found no lead in City-owned service lines. Inspections of customer-owned lines began in March 2022 under the EPA's Lead and Copper Rule Revisions, and the 2025 water quality report says the City's initial inventory did not identify any lead. You can look up a property on the City's service line material map. Inspections are free; the City says inspectors may ask to check the outdoor hose bib but will not ask to enter your home and never sell anything.
• Tap testing. The 2025 report says lead and copper were not detected above the state reporting limit in water leaving the City's treatment plants, but can enter water from plumbing inside homes and businesses. In the most recent required round of tap sampling (2023), 56 homes were tested, none was above the lead action level, and the next system-wide study is set for 2026, with selected homes contacted to take part.
• Reducing exposure at home. The EPA's lead in drinking water page says: "Use only cold water for drinking, cooking and making baby formula," and "Remember, boiling water does not remove lead from water." It also says: "If you use a filter, make sure you use a filter certified to remove lead." The City's report suggests running the tap for 30 seconds to 2 minutes when water has been sitting for several hours, and cleaning faucet aerators regularly.
• Testing your own water. The EPA calls testing "the only sure way of telling whether there are harmful quantities of lead in your drinking water." The City links to the State Water Board's map of state-certified laboratories, and the Water Quality Hotline, 619-668-3232, answers questions about lead, private labs and service line inspections. The EPA Safe Drinking Water Hotline is 1-800-426-4791.
• Schools. The State Water Board's lead sampling in schools page says Assembly Bill 746 required community water systems to test lead levels at public K-12 school sites built before January 1, 2010, by July 1, 2019; the program has ended and its results can be downloaded from that page. The City's 2025 report says it tested 281 schools in 2017, 2018 and 2019, and that for results at a particular school you should contact the school or check the district's website.

Every year the City publishes a Drinking Water Quality Report, also called the Consumer Confidence Report, which the EPA and the State Water Resources Control Board require. Its water quality reports page says a new report for the previous year comes out by July 1, and keeps past reports back to 2007.

• The 2025 report. Read it in English or Spanish (PDFs). It says the City's tap water met all state and federal drinking water health standards in 2025, and explains where the water comes from (mostly imported through the San Diego County Water Authority, plus local reservoirs).
• Find your column. City water is treated at the Alvarado, Miramar or Otay treatment plant, and the report's tables list results for each. The report says some neighborhoods can get water from either of two plants, so you may need to look at more than one column. (The City's Otay plant is not the Otay Water District.)
• Other numbers people ask about. The report says fluoride is adjusted to an optimal 0.7 ppm, as state regulations require, and averaged 0.7 ppm in 2025. It also lists bacteria monitoring (an average of 133 distribution samples a week), disinfection byproducts, and unregulated contaminants such as PFAS tested under the EPA's monitoring program.
• Questions about the report. The Water Quality Lab, 619-668-3232; for help in another language, the report lists 619-515-3500. The State's drinking water program is at the Division of Drinking Water.

The City's scams and imposters page warns about people posing as water utility workers who offer to inspect plumbing, sell water treatment devices or make false claims about water safety. It says City water workers do not need to enter your home unless you have scheduled a water-use survey, do not collect bill payments in person or sell door to door, and do not sell or install filters or other devices on your property. To check whether someone is a City employee, call 619-515-3525; for suspicious activity, SDPD's non-emergency line is 619-531-2000; if someone tries to force their way in, call 911.

For City water customers, water quality concerns go to the Public Utilities Water Quality Lab: 619-668-3232 or [email protected], as listed on the City's water quality page. As of November 4, 2026, the City's guide to Get It Done reports has no report type for drinking water quality and tells residents to call 619-515-3525 for water leaks. Have this ready:

• Where. Your address or the nearest cross streets (for example "near Elm Street and 30th Street"), and whether it is one tap, the whole building, or neighbors too.
• What. The color, cloudiness, particles, smell or taste; hot water, cold water or both; and whether outdoor hose bibs run clear.
• When. When it started, whether there has been street work, a main break or a shutoff nearby, and what you have tried (flushing, and for how long).
• A photo. A clear glass of the water against a white background shows color and cloudiness well.