Your hot water heater can provide an emergency water supply – here’s how

Following a large-scale emergency, your water supply may be interrupted. A hot water heater can provide you with a valuable source of water for emergency use. Here’s what you should know about drinking from your hot water heater:

Step 1:  Ensure the water in the tank stays clean.  

To keep contaminated water from entering your tank, turn off water to the house/building.  If you can’t shut off water to the entire house/building, shut off water supply where it enters the water tank – turn the water supply valve/tap clockwise.

Step 2:  Cut off power to the tank.

You don’t want to run your water heater without water in it, so turn off power:

– ELECTRIC water heater: flip the breaker supplying electricity to the appliance.    

– GAS water heater: shut off the gas to the tank. 

Step 3:  Allow the water to cool.

This will take hours.

Step 4:  Attach a hose (or place a pan/container below the tap/faucet). 

Near the bottom of the tank is the drain tap.  Attach a washing machine hose or garden hose to it or place pan/container under tap/faucet.  Do NOT open the tap yet!

Step 5:  Break the vacuum. 

Water won’t come out of the tank until air is allowed in.  Disconnect the hot water line at the top of the tank. If you can’t get the line off, turn on a hot water faucet in the house to allow air into the tank. 

Step 6:  Collect the water. 

Open the valve/tap (turn counter-clockwise) at the bottom of the tank and collect the water in a clean storage container. The first few gallons may contain rust and/or sediment.  Let it settle before using it.

Step 7:  Treat the water. 

Add bleach, stir, and let the water stand for 30 minutes. – Regular, bleach (5.25%), plain bleach, not scented or splash-proof – add 8 drops per gallon.

– Concentrated bleach (8.25%) – add 5 drops per gallon.  

Step 8: Allow the tank to fill completely before restoring power to the water heater. 

Here’s what you can do today, BEFORE disaster hits:

1. Print this information and tape it to the wall beside your water heater.

2. Identify the water supply valve (see below) and mark it: WATER SUPPLY LINE 

To identify the water supply line, run the hot water from any sink.  Touch the two pipes attached to the top of the water heater. The “supply” line will be the colder one.  Mark the pipe or associated tap/valve as “supply”. This will be the one to close (turn clockwise) in an emergency so that contaminated water will not go into the tank as you drain the clean drinking water that is stored in it. 

Sketch by Erika Mazza-Smith (@bloobberry on Instagram)