Monrovia Plumbing Services: Older Homes, City Sewer Backups and Old Town Pipes

The Census Bureau's 2020 to 2024 estimates put the median year built in Monrovia at 1962. About 70 percent of the city's housing units were built before 1980, and roughly 47 percent before 1960. The city's own Housing Element says only that its housing stock is older than in many other cities. It does not list pipe materials, and neither do we.

What age does mean in practice is that supply lines, shutoff valves and drain pipes may be original. When a house has had two or three leaks, the plumber should be asked what material is in the walls and how much of it is left. For how that decision is made, see repiping an older home. When the source is hidden, the first step is leak detection visits.

The City of Monrovia owns, operates and maintains the public sanitary sewer collection system, about 93 miles of mains. The city's own page says to call Public Works immediately for a backup or an overflowing manhole, at (626) 932-5575. If water is backing up inside the house and no manhole is overflowing, the stoppage may still be in your own line, and a plumber can find out.

A slow sink or tub is usually a branch-line clog that a snake or a hydro jet clears. Several fixtures backing up at once point toward the main drain. Kitchen drains in older homes collect grease, and tub drains collect hair and soap. Tell the dispatcher which fixtures are affected so the right equipment arrives. For the methods, see drain cleaning and clogs.

• Water heaters: for a tank that leaks or no longer heats, see water heater service; for a worn-out one, see water heater replacement options; for an on-demand unit, see tankless unit help.
• Fixtures: toilets that run, faucets that drip and shower valves that leak belong to bathroom fixture repair.
• Gas lines: for a new appliance or a gas smell, see gas line pressure testing and repair, and remember that a smell means leaving the house first.
• Sewer lines: for repeated backups or roots, camera work and the repair choices are in main line sewer repair.
• Slab leaks: for a warm floor spot or a running-water sound, see slab leak testing.

A Monrovia mailing address does not always mean a city address. Los Angeles County Regional Planning describes the South Monrovia Islands as a cluster of unincorporated communities bordering the city, including Mayflower Village and South Monrovia Island, and the county page does not say who provides water or sewer service there.

That matters for permits and for who answers a sewer call. If you are near the city's edge, check your water bill for the utility name and ask the city or the county which jurisdiction covers your parcel before a permit is applied for. County Regional Planning is at (213) 974-6425.

The city runs its own water utility through Public Works. Its water comes from groundwater in the Main San Gabriel Basin, and the Public Works number for water questions is (626) 932-5575. The city's pages do not mention another water company, but your bill is the way to confirm which supplier serves you.

Permits run through the Community Development Department's Building and Safety Division at 415 S. Ivy Ave. The city lists a Mechanical, Electrical and Plumbing permit among its application types. We did not find a direct Building line or counter hours, so City Hall, (626) 932-5550, is the number to call. Shops and restaurants in Old Town, along Myrtle Avenue and Duarte Road, are covered under commercial plumbing calls.

Calls also come in for disposal service, water damage services, replacing a water line and whole-house water filtration. For how an urgent call is handled at any hour, see the homepage.