How much water do I need for a Cascadia earthquake?

Water is your #1 survival supply. Humans can survive weeks without food, but only a few days without water. Bluntly, having water can mean the difference between life and death. Because of this, it’s important to plan ahead and store water for a Cascadia earthquake.

The recommendation for a Cascadia Subduction Zone earthquake is to store:

1 Gallon Per Person Per Day for 2 Weeks = 14 Gallons Per Person 

Why so much?

Well, a Cascadia earthquake will shake for 3 to 5 minutes, damaging the water system and making it inoperable for months. So, whatever water you have on hand when the earthquake happens is likely all you’ll have for a couple of weeks (until relief arrives).

What does 14 gallons of water look like?

Take the amount pictured above and multiply by the number of people and pets in your household.

The gallon per person per day covers both drinking and sanitation. Most people need about 3 quarts a day to be well hydrated, but it varies depending on age, physical condition, climate and health. People who might need additional water include nursing mothers, sick people, children or any of us on a scorching summer day. 


Did You Know?

You should turn off your water after a large earthquake

After a large earthquake, turn off your household water supply at the main. This keeps contamination from the ruptured water system out of your pipes, preserving safe water in your lines. It also keeps gravity from draining the water in your pipes if there’s broken pipes in the system. Shut the water off by turning the meter valve near the curb clockwise. If you have an interior shut-off valve where pipes enter your home, you can shut it off there.

You can use your water heater as a source of water

Have a tank water heater?  You can use the water inside as long as you’ve shut off your water at the main. Don’t count on it being your main source of water though, it may become inaccessible or damaged in the earthquake. Think of it as bonus water and remember it needs to be purified before drinking it. For instructions on how to safely access water from your water heater click here.


Make sure you have 2 weeks of water stored so you don’t get caught without. All of our two week home earthquake kits have the recommended water storage for a Cascadia earthquake.

Spread the preparedness word!