Storms get the headlines, but a lot of residential water damage starts inside the house: a supply line under a sink, a washing machine hose, a water heater at the end of its life, or an old pipe that finally gives way. Marin's housing stock skews older, and older plumbing means more risk. The good news is that these leaks are among the most preventable.
Supply lines. The flexible lines connecting toilets, faucets, dishwashers, ice makers and washing machines to your plumbing. Older rubber lines can crack or burst without warning. Braided stainless steel lines are a common, inexpensive upgrade, though even those should be inspected and replaced periodically per manufacturer guidance.
Water heaters. Tank water heaters can eventually leak as tanks corrode. Signs include rust-colored water, rumbling, moisture around the base, or a corroded tank. Many water heaters sit in garages, closets or crawlspaces, where a leak can go unnoticed.
Old pipes. Some older homes still have galvanized steel pipes, which corrode from the inside, or aging fittings. Homes in San Anselmo, Ross, San Rafael and Mill Valley often date to the early and mid-1900s. If you're not sure what you have, a licensed plumber can tell you.
Slab leaks. Many mid-century homes, including Eichlers in Terra Linda and Lucas Valley, have pipes or radiant heating under or in concrete slabs. Warm spots on the floor, the sound of running water, or an unexplained spike in your water bill can be signs.
Drain and sewer issues. Tree roots, especially from Marin's oaks and redwoods, can intrude into older sewer laterals and cause backups.
Marin rarely sees extended hard freezes at most elevations, but cold snaps do happen, especially in inland valleys and higher elevations. Insulate exposed pipes in crawlspaces, garages and exterior walls, and disconnect garden hoses when a freeze is forecast. Keep an eye on NWS Bay Area freeze warnings.
Water from a burst pipe on an upper floor can travel through ceilings, walls and floors before you see it. Restoration providers use moisture meters to find where it went. The CDC recommends drying fully and quickly, within 24–48 hours, after flooding to help prevent mold (CDC). Our burst pipes page explains the process.
If you own a vacation property in West Marin or rent out a home, consider:
Some of the sneakiest leaks come from appliances. Refrigerator ice-maker lines are often thin plastic tubing that can crack behind the fridge, leaking slowly into the subfloor for weeks. Dishwashers can leak at the supply connection or drain hose under the cabinet. Washing machines can fail at the hose or the drain standpipe. A few habits help: pull the fridge out once a year to check the line, look under the dishwasher toe kick with a flashlight, and don't run the washer or dishwasher when nobody is home. Leak sensors under each appliance are inexpensive insurance.
Leak happening now? Shut off the water, then submit a request to connect with an independent local provider. Read our first 24 hours guide while you wait.
Follow manufacturer guidance and inspect at least annually for bulges, corrosion or kinks.
Warm spots on the floor, sounds of running water, or an unexplained increase in your water bill.
Usually a licensed plumber repairs the pipe; a restoration provider handles drying.
Yes. Ongoing moisture from slow leaks can lead to mold in cabinets, walls and subfloors.
Shutting off the main, or using an automatic shutoff valve, reduces risk while you're away.
This article is general information, not legal, insurance or medical advice. Sources are linked in the text.