Basement and Garage Flood Cleanup in California

Do California homes have basements, and what counts as one here?

Full basements are uncommon in much of California, so the phrase here usually means something else: a below-grade room, a lower floor cut into a hillside, a garage that sits lower than the street, or a pit that holds a sump pump. All of them collect water the same way, because water runs downhill and settles.

If your home sits on a slab or on a raised foundation over a crawl space, you probably have none of these, and the crawl space page or the slab leak page may fit better. If you do have a lower level, this page is for you. A call reaches a local water damage restoration team that can handle the pumping and drying.

Why do below-grade rooms and garages flood?

Because they sit below the water around them. Storm runoff, a saturated hillside or a full street drain pushes water toward the lowest openings, which are often a garage door, a stairwell or a window well. Pipes and appliances add a second cause from within.

• Surface runoff from a driveway or street that slopes toward the garage door.
• Groundwater that rises after long rain and seeps through floor joints and walls.
• Plumbing failures, including a water heater or washer in the garage. The water heater leak page covers those.
• Sewer backup through a floor drain in a low room, covered on the sewage backup page.
• A failed sump pump or a power cut during the storm that needed it.

NOAA says a few atmospheric river events deliver about 30 to 50 percent of annual precipitation in the West Coast states. Low rooms feel those storms first. Our storm and flood damage page covers the wider picture.

What should I do first when a basement or garage is under water?

Stay out of the water until the power is off. Low rooms often hold outlets, a water heater, a panel or a freezer, and water carries electricity. If you cannot reach the shutoff from dry ground, leave the room alone and call your utility or an electrician.

1. Keep out of standing water that touches outlets, appliances or the electrical panel.
2. Cut power to the area from a dry spot, or have the utility do it.
3. Turn off the water supply if a pipe or appliance is the cause.
4. Photograph the water line on walls and the stored items before moving anything.
5. Call your insurer to report the loss and ask how the water will be classified.
6. Request a restoration team for pumping and drying, and ask how it plans the pump-out.

Never run a gasoline pump or generator indoors or in an attached garage. Use the guide on what to do after water damage for the general sequence.

Who removes the water, and how is it done?

A restoration team usually starts by removing the standing water with pumps or extractors, then takes out what cannot be saved and dries the rest. The order matters, because drying equipment cannot work while the floor is still under water.

Restoration teams differ in how they pump out a flooded room, and some do it in stages while the ground outside stays saturated. Ask each one to explain its plan and confirm timing, scope and price directly. Pumping is covered on the water removal and extraction page, and drying follows on the structural drying page.

The Contractors State License Board has a license lookup on its Hire a Contractor page.

What does a sump pit do, and what if the pump fails?

A sump pit collects groundwater at a low point so a pump can send it outside before it spreads across the floor. If your home has one, it is a safeguard worth testing. If the pump stops, the pit fills and the water goes where the pit once kept it away.

• Lift the cover and look for debris, silt or a stuck float.
• Check that the discharge line runs away from the house.
• Remember a power cut can stop an electric pump just when the storm is worst.
• Ask a plumber or drainage contractor about a backup power option.

Many California homes have no sump at all, and a garage may have only a floor drain. If you cannot say where water in your lower room is supposed to go, find out before the next storm.

Is the water in a basement or garage dirty?

Assume so. The IICRC S500 standard puts rising flood water and outside surface water in Category 3, the grossly contaminated class. A garage adds its own risks, because stored paint, fuel, fertilizer and cleaners can mix with the water and spread across the floor.

• The CDC recommends rubber boots, gloves and goggles for cleanup and says never to mix bleach with ammonia or other cleaners.
• The EPA says to call in a professional experienced with contaminated water when sewage is involved.
• Keep children and pets out until the room has been cleaned.

Containers that float or tip should be handled with care and set aside for proper disposal by your local program. The categories and classes guide explains how the water type shapes the cleanup.

What gets saved and what gets thrown out?

Hard, non-porous things usually clean up. Soft, porous things usually do not, especially after contaminated water. The CDC says to remove soaked carpet and upholstery that cannot be dried right away. Photograph each item before discarding it, because your insurer may want to see them.

The EPA says to dry water-damaged areas and items within 24 to 48 hours to prevent mold. Slow drying in a low, closed room is a common way for mold to start, and the mold guide explains what to watch for.

Does insurance cover a flooded basement or garage in California?

That depends on the water. The California Department of Insurance says homeowners policies do not cover flood but do cover other kinds of water damage. The NAIC says damage from ground water or rain runoff is typically not covered, while damage from a home's plumbing typically is.

• The Triple-I says sewer backups are not covered by a typical homeowners policy or by flood insurance, and need a separate endorsement.
• FEMA says most homeowners insurance does not cover flooding. A flood policy generally takes effect 30 days after purchase, according to the California Department of Insurance.
• The Department also says mold from a covered peril may be covered, so report quickly.

Under 10 CCR 2695.5(e), an insurer must acknowledge a claim within 15 calendar days of notice. Under 2695.7(b), it has 40 calendar days after proof of claim to accept or deny. Details are in the insurance claims guide, and the flood insurance guide covers separate policies.

How do I keep a low room from flooding again?

Start by sending water somewhere else. Most repeat floods in low rooms trace back to grading, drains or a failed pump. Fix what let the water in before you rebuild, or the next heavy storm will repeat the damage and the expense.

• Make sure the ground and driveway slope away from the garage door and walls.
• Keep gutters, downspouts and yard drains clear, and extend downspouts away from the foundation.
• Test a sump pump before the wet season, if you have one.
• Raise stored boxes onto shelves and avoid keeping paper or fabric on the floor.
• Ask a plumber whether a backwater valve makes sense for floor drains, which the prevention guide also touches on.

If water is already inside, send a request through this site and it will reach a local water damage restoration team that serves your area. Contacting us does not obligate you to hire anyone.

Sources: NOAA Research, Atmospheric Rivers; California Department of Insurance, Residential Property Claims Guide; California Department of Insurance, Flood Insurance Resources; 10 CCR 2695.5; 10 CCR 2695.7; NAIC, Homeowners Insurance; FEMA, Don't Have Flood Insurance; Triple-I, Which disasters are covered by homeowners insurance; IICRC S500; CDC, About Mold and Your Health; EPA mold and moisture guide; EPA, Mold cleanup in your home; CSLB, Hire a Contractor.