Flooding
River flooding usually gives you hours of warning — not minutes. The question isn't whether you'll have time. It's whether you'll use it. Here's how to read the signs, protect what you can, and leave when it's time.
The hours before the water
Tom wakes at 4 AM on a Wednesday in December because he can't sleep when it rains like this. He and Maria live on Prindle Street in Centralia, half a mile from the Chehalis River, in a house built in 1958 on a street that was platted before anyone in Lewis County cared about floodplains. The house has flooded twice — 2007 and 2009. Both times, two feet of brown water in the living room. Both times, everything below knee height was ruined. After the second time, they raised the furnace and the electrical panel. They couldn't raise the house. Too expensive. So they learned to read the river instead.
Tom opens his phone and checks the USGS gauge at the Grand Mound station. The Chehalis is at 67.2 feet and rising. Flood stage is 65 feet. Major flood stage is 70. The National Weather Service forecast shows the crest at 71.5 feet by 7 AM. That's worse than 2009.
He wakes Maria. They don't argue about it. They've had this conversation twice before and once more in practice, last October, when the river hit 64 feet and they did a dry run. The dry run is why the next four hours go the way they do.
First: the basement. Tom moves the plastic bins — documents, photo albums, the kids' school projects Maria can't let go of — from the basement shelves to the truck bed. The bins are already packed. They've been packed since September. After the second flood, Maria said: "I'm not going to lose the same things three times." She meant it. Everything below three feet is either replaceable or already in a bin.
Second: the house. Maria unplugs everything at the wall. Moves the couch cushions upstairs. Puts the floor lamps on the dining table. Turns off the water main, the gas, and the breaker panel — she does this in the order Tom wrote on the card taped to the panel box. The card has been there since 2010. The tape is yellowed. The instructions still work.
Third: the neighbors. Tom walks to the Ortegas' house next door. They moved in last year. They've never seen the river this high. He tells them: it's going to flood, probably by late morning, and they should move anything they care about off the ground floor. He says it calmly, because panic is contagious and calm is useful. The Ortegas' faces change when they understand he's serious.
By 6:30 AM, Tom and Maria are in the truck. The bins are in the back, covered with a tarp. The dog is in the cab. They drive east on Highway 6 toward Maria's sister's place in Morton, thirty miles upriver and 400 feet higher. The rain hasn't stopped.
The water reaches Prindle Street at 9:15 AM. It peaks at fourteen inches inside the house — less than 2009, because the city's upstream retention work took some of the crest. The Ortegas get two inches. They'd moved everything off the floor by 7 AM. They tell Tom later that they almost didn't.
What's happening in the watershed
Flooding in the Pacific Northwest
The Pacific Northwest floods because of its geography. Steep mountain ranges catch moisture-laden air from the Pacific and wring it out as rain — sometimes extraordinary amounts. The water runs off into river systems that pass through populated valleys on their way to the coast or the Sound. When the rainfall exceeds what the soil can absorb and the rivers can carry, the water goes where it always goes: the floodplain. The floodplain is where we built.
The primary driver of PNW flooding is the atmospheric river — a narrow band of tropical moisture that can deliver a month's rainfall in 48 hours. The winter of 2025-2026 demonstrated what happens when multiple atmospheric rivers hit in sequence: saturated soil, full reservoirs, and rivers that have nowhere to put the water. Leavenworth, a town beloved for its Bavarian holiday village, was gutted. Communities across western Washington saw levels not reached in decades.
Why the same places flood again
Flooding in the PNW is not random. The Chehalis basin floods because it's a broad, low-gradient valley with inadequate channel capacity. The Skagit River floods because its headwaters drain the western Cascades and the river passes through some of the flattest agricultural land in the state. The Snoqualmie floods because the falls create a natural bottleneck that backs water up into the valley.
If your property has flooded before, it will flood again. This is not pessimism — it's hydrology. The FEMA flood maps show the 100-year and 500-year floodplains, but "100-year flood" doesn't mean once a century. It means a 1% chance in any given year. The Chehalis basin has had "100-year floods" three times since 2007.
The warning you actually get
Unlike earthquakes, floods give you time. The National Weather Service issues flood watches (conditions favorable) and warnings (flooding expected or occurring). USGS river gauges provide real-time water levels for most major rivers. If you live in a floodplain, you can monitor the gauge for your river and know, within hours, when the water will reach your property. That time is your advantage — but only if you've planned what to do with it.
Climate and the trend line
Warmer air holds more moisture. Atmospheric rivers are getting wetter. Rain-on-snow events — where warm rain falls on an existing snowpack and melts it, doubling the runoff — are increasing as the snow line rises. The trend is toward more frequent and more severe flooding in the river valleys of Washington, Oregon, and British Columbia.
This isn't a reason to panic. It's a reason to prepare. If you live in a floodplain, preparation isn't optional — it's the cost of living where the water goes.
What to do
Before, during, and after
Before flood season
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Know your floodplain
Check FEMA flood maps for your property. If you're in a 100-year or 500-year floodplain, flood insurance is strongly recommended — and may be required by your mortgage. Standard homeowner's insurance does not cover flood damage. This surprises people every single time.
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Know your gauge
Find the USGS river gauge closest to your property at waterdata.usgs.gov. Learn the flood stage and major flood stage for your gauge. Bookmark it. When heavy rain starts, checking the gauge every few hours tells you exactly how much time you have. Tom checks Grand Mound. You should know your equivalent.
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Elevate what you can
Furnace, water heater, electrical panel, washer/dryer — if they're in a basement or on a ground floor that has flooded before, raise them. This costs money, but replacing a furnace after a flood costs more. If you can't raise them, know how to shut them off quickly.
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Pack your bins
Anything irreplaceable that lives below potential water level should be in a waterproof bin, ready to move. Documents, photos, keepsakes, hard drives. Pack them now, in the dry season, when you're not rushed. Maria's rule: "I'm not going to lose the same things three times."
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Write a shutdown card
A laminated card taped to your breaker panel: the order in which you shut off water, gas, and electricity. Under stress, sequence matters. Write it down when you're calm so you can follow it when you're not.
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Get flood insurance
Through the National Flood Insurance Program or a private insurer. There is typically a 30-day waiting period before a new policy takes effect — you cannot buy it when the river is already rising. Buy it now. If your property has flooded before, this is not optional.
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Know your neighbors
Especially new ones. The Ortegas had never seen the Chehalis high. Tom's calm warning at 5 AM gave them four hours they wouldn't have had. If you've been through a flood, you know what it looks like. Your new neighbor doesn't.
When the water is coming
Never drive through floodwater
Six inches of moving water can knock you down. Twelve inches can carry a car. More than half of all flood deaths in the US happen in vehicles. If the road is flooded, turn around. "Turn around, don't drown" exists as a slogan because people keep dying doing the thing it says not to do.
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Monitor the gauge and NWS alerts
Sign up for emergency alerts from your county. Watch the USGS gauge. When the river passes flood stage, start your plan. You know the number. You know how fast it's rising. Use the time.
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Move irreplaceable items to high ground
The bins go in the truck. Everything else on the ground floor goes up — to the second floor, onto tables, into the attic. You have hours. Use them. Furniture can be replaced. Photo albums cannot.
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Shut down the house
Follow the card. Unplug appliances. Turn off water main, gas, and breakers. This prevents electrical damage, gas leaks, and contamination of your water system when floodwater enters.
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Warn your neighbors
Walk over. Tell them what you know. Be calm and specific: "The river is at 67 feet and forecast to crest at 71. That means water on our street by mid-morning. You should move your things off the floor." Information, delivered calmly, saves more than panic.
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Leave before the water arrives
Do not wait to see if it's as bad as forecast. If you're in the floodplain and the crest is predicted above your property level, leave. Go to family, friends, or a shelter on higher ground. Take your bins, your pets, your medications, your go-bag. The house will be there when the water goes down. You need to be somewhere it isn't.
After the water recedes
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Don't enter until it's safe
Floodwater is contaminated — sewage, chemicals, debris. Wear rubber boots and gloves. Don't turn on electricity until an electrician has inspected the panel. Check for structural damage: shifted foundation, buckled floors, waterlogged walls.
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Document everything before cleaning
Take photos and video of all damage before you move or clean anything. This is your insurance claim. Photograph water lines on walls, damaged belongings, structural issues. Your insurance adjuster needs to see what the water did, not what it looks like after you've cleaned up.
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Dry out within 48 hours
Mold starts growing on wet materials within 24-48 hours. Open windows, run fans, use dehumidifiers if you have power. Remove waterlogged drywall, carpet, and insulation. Anything that absorbed floodwater and can't be thoroughly cleaned needs to go. This is the hard part — but mold damage is worse than flood damage if you let it establish.
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Keep records for insurance and FEMA
Save receipts for everything — cleanup supplies, temporary housing, repairs. If a federal disaster is declared, FEMA assistance may be available. File your insurance claim immediately. The process is slow. Starting early matters.
What to have ready
Your flood supplies
Flood preparedness is different from earthquake or wildfire prep. You're not surprised — you're racing a clock. The supplies that matter most are the ones that let you use your warning time well: pre-packed bins, a shutdown routine, and a plan that doesn't require decisions under stress.
For the full checklist with quantities, see our Build Your Kit page.
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Critical
Waterproof bins (pre-packed)
Everything irreplaceable goes in sealed bins: documents, photos, hard drives, keepsakes. Pack them now, store them where you can grab them fast. The bins ARE the preparation. When the gauge hits flood stage, you move them to the truck and go.
Hardware store. Heavy-duty plastic bins with locking lids. Label them.
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Critical
Flood insurance
Homeowner's insurance does not cover flood damage. NFIP or private flood insurance does. 30-day waiting period on new policies — buy it before you need it. If your home has flooded before, this is not optional.
Through your insurance agent, or directly via floodsmart.gov for NFIP.
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Critical
Shutdown card (laminated)
A laminated card taped to your breaker panel with the sequence: unplug, water off, gas off, breakers off. Under stress, you follow the card. You don't think. You execute.
Write it yourself. Laminate at an office supply store. Tape it to the panel.
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Important
Rubber boots and waterproof gloves
Floodwater is contaminated — sewage, chemicals, fuel, debris. You'll need these for re-entry and cleanup. Do not wade in floodwater in regular shoes.
Hardware store. Knee-high rubber boots. Heavy-duty waterproof gloves.
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Important
Sump pump (if applicable)
If your basement floods, a portable sump pump gets the water out faster than gravity. Battery-backup or generator-powered, since the power may be out.
Hardware store. Size it for your space. Test it before you need it.
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Important
Camera / phone (charged) for documentation
Your insurance claim starts with photos. Document damage before cleanup. Photograph water lines, damaged items, structural issues. Video is even better.
Your phone. Keep a portable charger in your go-bag.
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Recommended
Dehumidifier and fans
Mold starts within 48 hours of flooding. Drying the house fast is critical. A dehumidifier and box fans in every affected room.
Hardware store. If power is out, a generator running a dehumidifier is a smart use of fuel.
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Recommended
Sandbags or flood barriers
Sandbags buy you inches, not feet. They're useful for diverting shallow water away from doorways, not for holding back a river. Know their limits. Many counties provide free sandbags before flood events.
Your county emergency management office usually distributes free sand and bags before major events. Check before flood season.
What Tom and Maria did right
They come back on Friday. The water is gone but the smell isn't — river mud and something chemical, a sharp undertone Tom recognizes from the last two times. Maria puts on the rubber boots she keeps in the truck and walks through the front door. Fourteen inches. She can see the water line on the wall, a brown stripe across the living room like a ruled line in a notebook.
The couch cushions are upstairs, dry. The floor lamps are on the dining table, dry. The furnace, raised in 2010, is above the line. The electrical panel, also raised, is dry. The bins — the documents, the photo albums, the kids' school projects — are in Morton at Maria's sister's house, forty miles away and 400 feet higher. Dry.
The carpet is ruined. The drywall below eighteen inches is ruined. The baseboard trim is ruined. Tom has his phone out, photographing everything before they touch it. The insurance adjuster will come Monday. The FEMA inspector, if the disaster declaration comes through, sometime after that.
Maria calls the Ortegas. Two inches on their ground floor. They caught it in time — everything was off the floor by 7 AM, four hours before the water arrived. They say thank you. Maria says don't thank us, just tell the next new neighbor.
By Saturday, Tom has the carpet pulled and the baseboards out. The dehumidifier is running. Two box fans. Windows open. He'll have the drywall cut back to two feet by Monday. Mold doesn't get 48 hours. Not this time.
This is their third flood. It'll happen again. The river doesn't care about the retention project or the levee improvements or the floodplain zoning debates in Olympia. It does what water does. Tom and Maria can't change that. But they can be ready. And being ready means fourteen inches of water is a week of cleanup, not a catastrophe. It means the photo albums are in Morton. It means the Ortegas knew.
You can be Tom and Maria. Bins, a shutdown card, a gauge bookmarked on your phone, and a neighbor you've talked to before the rain starts. The river gives you hours. Use them.