Basement Water Damage Guides · Basement Water Damage Guides

Basement Flooding in an Apartment Building

Basement flooding apartment building residents face is a shared problem, because the basement is a common part of the building and the water in it can affect everyone who lives there. A resident who finds water should tell the building manager first, stay out of the flooded room, and warn the other residents, because the basement may hold the building's services, storage, and laundry, and the water can reach them all. The safety rules are the same as for a single home, but the people involved are more numerous.

📞 Call Now — (877) 624-0105 All Basement Water Damage Services

✓ Written for California homeowners
✓ Visit first, then a plan
✓ Call to arrange a visit

Basements are uncommon across most of California, and they exist mainly in older buildings and some hillside areas, so this guidance applies to a smaller group of buildings. For those buildings, though, a basement flood is a problem for the whole building, not for one resident alone. The [commercial basement water damage cleanup](/commercial-basement-water-damage-cleanup/) page describes the commercial cleanup service in general terms.

Tell the building manager first

Tell the building manager first, because the basement is a shared part of the building and the manager is responsible for it in general terms. Describe what can be seen from a safe distance: where the water is, how deep it looks, whether it is still rising, and whether it followed rain or appeared on a dry day. The manager can arrange for the water to be dealt with and can tell the residents what to do.

No legal advice is given here, because the duties of a resident, a landlord, and a building manager vary. The resident's job is to report the flood promptly and to stay safe, not to fix it.

Stay out and warn the residents

Stay out of the flooded basement, and warn the other residents that the room is out of bounds. Never enter a flooded basement, because submerged outlets and panels make the water dangerous, and floodwater is not safe water. A resident who does not know the water is there may walk downstairs without knowing the danger, so a clear warning to the building matters as much as the report to the manager.

Keep children and pets away from the basement door, and close the door if you can do so from dry ground. The safety rule applies to everyone in the building, not only to the person who found the water.

Basement Flooding in an Apartment Building — California basement water damage guide

Shared services in a basement

A basement in an apartment building often holds shared services: the water heater, the electrical panels, the laundry, and the storage for the building. Water that reaches those services can affect the whole building, not only the basement, and the power or the hot water for the building may be involved. Do not touch electrical items, switches, or outlets in standing water, and do not try to switch off the power from inside a flooded basement.

If the power needs to be shut off, do it only from a dry place and only if it is safe to do so; otherwise leave it and call a professional. A professional can deal with the electrics once the water has been removed.

Storage and laundry in a flooded basement

Storage and laundry in a flooded basement are often the belongings most affected, because residents store boxes and use the laundry in the shared room. Do not carry items out of a flooded room, and do not reach into the water to pull something out. The belongings that matter most are the ones that are still dry, and they can be moved from dry ground while waiting.

Keep a list of what was in the room and what was damaged, because that record helps both the cleanup company and any insurer. Do not throw damaged items away before the manager or the insurer has had a chance to see them, unless they are a health risk.

Sewage in a shared basement

Sewage in a shared basement is a professional-only job, and no do-it-yourself sewage-cleanup advice is given here. A resident who finds sewage should stay out, keep everyone away, and tell the building manager promptly. The manager should arrange for a professional to deal with it. The [basement sewage cleanup](/basement-sewage-cleanup/) page describes the sewage cleanup service in general terms.

Do not handle items that have been in contact with sewage, and do not try to wash them yourself. Floodwater is not safe water, and sewage water is more dangerous still.

After the flood is dealt with

After the flood is dealt with, the building manager should tell the residents when the basement is safe to re-enter, and no resident should re-enter it before then. Keep a record of the flood, the report, and the work that followed, because that record is useful for the building and for any insurer. The [commercial basement water damage cleanup](/commercial-basement-water-damage-cleanup/) page describes the commercial cleanup service in general terms.

Do not re-enter the room until a professional has dealt with the water and the electrics. The room is safe to re-enter only when a professional has said so.

Key Takeaways

Tell the building manager first, because the basement is a shared part of the building and the manager is responsible for it in general terms.
Stay out of the flooded basement, and warn the other residents that the room is out of bounds.
A basement in an apartment building often holds shared services: the water heater, the electrical panels, the laundry, and the storage for the building.
Storage and laundry in a flooded basement are often the belongings most affected, because residents store boxes and use the laundry in the shared room.
Sewage in a shared basement is a professional-only job, and no do-it-yourself sewage-cleanup advice is given here.
After the flood is dealt with, the building manager should tell the residents when the basement is safe to re-enter, and no resident should re-enter it before then.

Your Next Step

If this guide matches what you found at home, the next step is a visit — not a guess. Call and describe what you found, and the visit is arranged from what you describe. The Commercial Basement Water Damage Cleanup page explains what that service covers, the Basement Flooding Cleanup page covers a related part of the job, and the services hub lists every service in one place.

While you wait, do not enter a flooded basement and do not touch switches, plugs or appliances in standing water. Floodwater is not safe water — keep pets and children clear of it.

Keep the guides on this site bookmarked: the first guide, the signs guide, and the preparation guide cover the checks worth repeating — after moving in, and after heavy rain.

Basement water damage help is available across California. See basement water damage cleanup in Rancho District, CA for one local example, or find your town on the service areas page.