Earthquakes risk in Idaho

You're standing in a 1970s ranch house in Pocatello, and the home inspector says the foundation is solid. But solid doesn't mean anchored. Idaho gets a level 3 of 5 for earthquake risk statewide. That's not California, but it's not nothing. The ground under eastern and central Idaho has moved before, and it will move again.

Who this hits hardest

Older homes take the hardest hit. Unreinforced brick, stone, or block foundations from before the 1970s are the ones that crack or slide off their footings. In eastern Idaho, Bonneville, Madison, Bannock, Bingham, and Caribou counties sit close to active faults. The 1983 Borah Peak earthquake, a magnitude 6.9, was centered in Custer County and shook homes across the region. Central Idaho counties like Lemhi, Blaine, and Custer feel it too. Northern Idaho — Kootenai, Bonner, Boundary — has its own faults. Even the Treasure Valley around Ada and Canyon counties gets occasional shaking, just less often. In the southeast corner, Bear Lake, Franklin, and Oneida counties sit near the Wasatch fault system that runs through Utah.

Mobile homes and manufactured homes on piers are vulnerable. So are houses on soft soils, hillsides, or fill. Renters: your landlord's policy won't cover your stuff. Condo owners: the HOA master policy may cover the building shell but not your interior or your belongings.

After the event — claims and repairs

First, check yourself and your family. Then check for gas leaks. If you smell gas, get out and call the utility from outside. Don't flip switches. Once it's safe, take photos of every crack, every fallen shelf, every broken window. Your insurer will ask for documentation.

Here's the insurance reality. Standard homeowners policies in Idaho exclude earthquake. You need a separate policy or an endorsement. Deductibles are usually a percentage of your dwelling coverage — often 10% to 20% — not a flat $500. So on a $300,000 house, you might pay the first $30,000 to $60,000 before insurance kicks in. That's why many people skip it. But skipping it means you're self-insuring. Idaho doesn't have a state-run earthquake insurance program. Ask your agent for a quote in writing.

FEMA can help after a presidential disaster declaration, but not every earthquake gets one. The Idaho Office of Emergency Management coordinates the state's response and works with local emergency managers. If a quake is bad enough, you might see FEMA Individual Assistance, SBA low-interest loans, or both. Keep receipts for hotel stays, repairs, and replacement items. Watch out for unlicensed contractors who show up after a disaster. Get three bids and check licenses.

Before the season starts

There's no earthquake season, but there is a before. The best time to prepare is a random Saturday, not the day after a shake.

If I had one weekend and a few hundred dollars, I'd strap the water heater to the wall, anchor the tall bookshelves and the TV, and put a pair of shoes under every bed. That's the first thing. Then I'd look at the foundation.

Retrofitting a house is more work. You or a contractor can bolt the sill plate to the foundation, brace cripple walls, and reinforce a masonry chimney. Some of these jobs need a permit. The Idaho Office of Emergency Management and your county building department can point you to local guidance. If you're buying a house, ask for the seismic retrofit history. A bolted foundation is a selling point.

Also: install an automatic gas shutoff valve. Know where your gas meter is. Store water — a gallon per person per day for at least three days. Keep a flashlight, a battery radio, and any medications in a go-bag. Practice Drop, Cover, and Hold On with your household. It takes 30 seconds.

Questions we get

Does my Idaho homeowners policy cover earthquake damage?

Usually no. Standard policies exclude earth movement. You need a separate earthquake policy or an endorsement. Deductibles are often 10% to 20% of your dwelling coverage, not a flat dollar amount. Ask your agent to show you the exclusion in writing.

I don't live near the Sawtooth fault. Do I still need to worry?

Yes. Shaking travels. The 1983 Borah Peak quake was felt across Idaho and into Montana and Wyoming. Faults run through eastern, central, and northern Idaho. Check the USGS hazard map for your county — it's free and public.

What's the first thing to do after a quake if my house looks fine?

Check for gas leaks, foundation cracks, and chimney damage. If you smell gas, leave and call from outside. Then take photos before you clean up. Even small cracks can become a claims issue later.

Official sources

• Idaho Office of Emergency Management
• USGS Earthquake Hazards Program
• Ready.gov — Earthquakes
• FEMA Earthquake Safety