Plumber in Claremont, CA: The City Runs the Main, You Keep the Lateral

Claremont permits: what the City says and where to file

The City of Claremont says permits are required when constructing, remodeling or enlarging a building or structure, and that permits are also required for other improvements to your property. It does not list plumbing jobs one by one on that page, so ask the Building Division whether your job needs one.

Permit issuance at City Hall runs Monday to Thursday, 7:00 a.m. to 5:30 p.m. Permits without plans are processed over the counter. Projects with plan sets are submitted electronically to [email protected].

Job type	How Claremont says it is handled
Permit without plans	Processed over the counter
Project with a plan set	Submitted electronically by email
Anything else on the property	Check with Planning and Engineering for other approvals

The Building Division line the City lists is (909) 399-5471. The City also lists a few staff numbers, and the permit technician post is shown as vacant, so use the division line and the email first.

Sewer: the City runs the main, and the lateral is the owner's

Claremont's 2025 Sewer System Management Plan says the City "is solely responsible for the operation, control, and maintenance of the City's sanitary sewer system." The same plan says Los Angeles County Code requires that property owners be responsible for maintenance of their house laterals. It adds that "The City is not responsible for problems within a privately-owned lateral."

The plan describes about 122 miles of gravity sewer lines. It also notes that some trunk lines belong to Los Angeles County Sanitation District No. 21, not to the City. One sentence in the plan describes the collection system as including "associated private laterals," so the line between public and private is not perfectly crisp.

1. Camera the lateral and save the video with the distance to the damage.
2. Ask the Public Works staff whether the fault sits on the City main or on the private lateral.
3. Get the answer in writing before you agree to a dig.

Our sewer repair order of operations explains the choices once the break is located.

Water comes from Golden State Water, not the City

The City says Golden State Water Company, a private company, provides water service to Claremont homes and businesses. It also says the City does not own, operate or manage water service or groundwater in Claremont. So a leak at the meter or a pressure problem goes to the company on your bill.

Golden State's Claremont service area includes Claremont and portions of Montclair, Pomona and Upland. Its 2025 report lists hardness at an average of 190 mg/L, or 11 grains per gallon, with a range from 97 to 330 mg/L. The water is a blend of treated groundwater and imported water from the State Water Project.

That average is high enough to leave scale on heating elements and fixtures. See the report-based softener sizing guide before buying a unit.

Watering and hardscape rules that touch plumbing calls

Claremont's City water page lists uses it prohibits at all times. They include hosing off sidewalks and driveways, watering lawns so that water runs off, and watering within 48 hours after measurable rain. A sprinkler leak that floods a walkway can therefore be a rules problem as well as a repair.

Golden State's Claremont page says it modified outdoor watering restrictions to allow watering up to three days per week, with even addresses on Sunday, Wednesday and Friday and odd addresses on Tuesday, Thursday and Saturday. That page is dated May 14, 2023, so confirm the current schedule with the company.

• Fix a broken sprinkler head before the next watering day.
• Find a wet patch with a meter test, using our irrigation leak tracing page.
• Keep the repair receipt if the company asks about a high bill.

Common calls from Claremont homes

• A main drain that backs up after laundry: jetting out a grease buildup.
• A water heater with scale noise: repairing a noisy tank.
• Pipes that fail one after another: replacing aging supply pipe.
• A leak under a bathroom sink: fixing a sink leak.

Claremont on the map

Boundaries between cities, unincorporated pockets and water districts sit close together here, so give the full street address when you call.