Hurricane Harvey wasn’t a surprise.

The eighth named storm of the 2017 Atlantic hurricane season, Harvey became the first major hurricane to make landfall in the United States since Wilma in 2005, snapping a record-setting 12-year calm streak. The city of Houston, Texas ended up in its crosshairs, along with much of the Gulf Coast into Louisiana and to the north in late August and early September 2017.

Forecasters saw the storm coming, but the damage it caused was unprecedented.

Over the course of four days, Harvey stalled over southeast Texas, dumping more than 40 inches of rain on some areas and causing once-in-a-lifetime flooding in an region that already sees its fair share of floodwaters. With peak accumulations of nearly 65 inches, the storm ranks as the wettest tropical cyclone in U.S. history and one of the most damaging / most expensive, inundating hundreds of thousands of homes and displacing more than 30,000 people across Texas alone.

In fact, according to a report following the storm released by MetStat Harvey is now considered a 500,000-year flood in some parts of Southeast Texas, meaning that it is the kind of destructive event that will happen just once every 500,000 years.

Health risks

The immediate damage from the storm was staggering, but the aftermath was (and is) far worse.

Hundreds of neighborhoods were wiped completely off the map, but thousands more were damaged by floodwaters but left standing, for owners to come back and try to pick up the pieces. That means one thing: mold.

As a general rule, insurers consider any part of a home or other structure that has been submerged under flood waters for any period of time to be a total loss. Beyond that, anything that has been underwater and not immediately dried off for 24 to 48 hours is likely home to growing mold. This includes everything from walls, floors, carpets, furniture, clothing, books and most everything else in the home, as well as spaces behind walls and under floorboards. Mold loves flooding.

Two things to know about mold: Exposure to it can cause severe symptoms, including eye and skin irritating, asthma attacks and more, depending on how susceptible a person is to it. And, important to remember when cleaning up after a flood, it is generally not covered by standard homeowners insurance policies unless it is cause by a specific event (usually water entering the home through a hole in the roof, or mold caused by a broken water pipe). Flood insurance is an add-on rider to your homeowners insurance.

Cleaning up

The Centers for Disease Control (CDC) he following steps to take when cleaning up a structure after a flood.

Protect Yourself: If you suffer from asthmas or have a weakened immune system, stay out of the building. Period. You are at higher risk of injury just by walking in the door. The same goes for children and the elderly. These sites are dangerous and shouldn’t be taken lightly. If you must go inside, wear a respirator that covers you mouth and nose as well as eye protection, shoe covers and heavy rubber gloves.

Contain the Mold: As soon as you leave the damaged structure, take a shower and change your clothes. Remove your shoes and leave all of your protective gear outside. If you don’t take care to contain the mold as you come and go from the flooded structure, it is easy to transport it back home or elsewhere.

Remove the Water: Using a wet / dry vacuum, remove all standing water and pull out any waterlogged materials, including carpets, drywall, etc. Start the drying process by opening all the doors and windows and airing out the home. Inside, open up all interior rooms, cabinets, closets, attic access, etc to allow for full airflow, using fans and dehumidifiers once its safe to use electricity again.

Start Cleaning: Starting with a mild solution of soap and water start scrubbing away all the mold you can see. Dry it right away. Tear out waterlogged drywall and complete remove all water from the area before painting or caulking.

Clean House: Throw away everything that can’t be cleaned or dried. Anything that was wet with floodwater, or can’t be cleaned and dried completely within 24 to 48 hours, has to go. If in doubt, throw it out.