Short answer: in Pomona, a leaking water heater should be shut off at the cold-water valve and inspected by a plumber. The City of Pomona states that any new, replacement, relocated or altered water heater needs a plumbing permit, and its groundwater averaged 260 mg/L hardness in its latest report, which is very hard. For water heater leak repair near you, start with the emergency steps.
Pomona’s water and what it means for water heaters
The City of Pomona Water Resources Department is the main water provider, with more than 30,000 connections and 38 wells according to the city’s 2020 Urban Water Management Plan. The plan also notes two small areas supplied by other agencies: Walnut Valley Water District, north of Valley Boulevard and west of Temple Avenue, and Golden State Water, in two small parcels near Foothill Boulevard.
The city’s 2024 water quality report shows groundwater hardness ranging from 160 to 360 mg/L with an average of 260 mg/L, about 15 grains per gallon by our conversion. The USGS classes anything above 180 mg/L as very hard. In hard water, scale builds up at the bottom of tanks and on connectors, and anode rods wear out sooner, which is why we see tank corrosion and crusted, leaking connectors on the list for Pomona homes.
| Topic | What we found | Where to check |
|---|---|---|
| Water supplier | City of Pomona Water Resources Department, with small areas served by Walnut Valley Water District and Golden State Water | Your water bill |
| Reported hardness | Groundwater 160 to 360 mg/L, average 260 mg/L (2024 report, 2023 data) | The city’s water quality reports |
| Permit rule | A plumbing permit is required for any new, replacement, relocated or altered water heater (city handout citing the 2022 California Plumbing Code) | City of Pomona Building Safety Division |
| Permit office | Development Services Department, Building Safety Division, 505 S. Garey Ave., (909) 620-2371 | Confirm hours with the city |
| ZIP codes | Including 91766 (Phillips Ranch), 91768 and 91769. There are more that we did not verify. | USPS lookup |
Phillips Ranch and the hill areas
Phillips Ranch is a neighborhood in the southwest of Pomona, ZIP 91766, and not a separate city, so Pomona’s rules apply there. Public references say it was developed starting in the 1960s. Homes that old have usually had their heaters replaced more than once, but the shutoff valves and connectors around a newer tank may still be much older, so ask the plumber to check them as well as the tank.
Neighborhoods on slopes may see higher static water pressure than those on flat ground. If the relief valve drips or pipes bang, ask for a pressure test. The California Plumbing Code calls for a pressure regulator where static pressure exceeds 80 psi. See relief valve leaks.
Permits and inspection in Pomona
Because the city is explicit that replacement needs a permit, ask your plumber whether the quote includes it and who will be home for the inspection. A permitted job also documents the bracing, relief valve discharge and expansion tank. Our water heater replacement guide lists what a compliant install includes.
The USGS reports that the epicenter of the 2008 Chino Hills earthquake was about 12 km south of Pomona. Few damage reports followed, but it is a reminder of why California requires new and replacement water heaters to be braced.
Need a plumber for this? Give the plumber your Pomona address so they can confirm coverage and say whether the permit is included.
Call +1 (909) 760-1466Nearby
Pomona’s neighbors include Walnut, where Walnut Valley Water District also serves a small part of Pomona, and Chino Hills, which borders Phillips Ranch. For a local Diamond Bar plumber, our main page lists the same steps and questions.
Frequently asked questions
Do I need a permit to replace a water heater in Pomona?
Yes. The City of Pomona states that a plumbing permit is required for any new, replacement, relocated or altered water heater. Ask the plumber to include the permit and inspection in the quote.
How hard is Pomona’s water?
The city’s 2024 report shows groundwater hardness between 160 and 360 mg/L with an average of 260 mg/L, which is above the 180 mg/L the USGS treats as very hard. Your tap may be a blend, so check the report.
Is Phillips Ranch part of Pomona?
Yes. It is a neighborhood in southwest Pomona, ZIP 91766, so the City of Pomona’s building and water rules apply there.
Does the city have a water heater leak program?
We have not found one, so call the Building Safety Division for permit questions and a plumber for the repair. The city’s water office can help with questions about supply and pressure.
Sources and further reading
Related guides
- Replacing a leaking water heaterWhen a leak means replacement, what a California-compliant installation includes, and how permits and bracing fit in.
- Leaking from the bottom: tank corrosionHow tanks wear out, what the anode rod does, and how to tell a failing tank from a fitting leak or condensation.
- Leaking T&P relief valveWhy the relief valve or its discharge pipe drips, which causes are harmless, and which are warnings.