Emergency Preparedness

Got Water?
MMWD has invested heavily in facility upgrades and employee training to help ensure our water is there when needed most. There are also some simple steps you can take on your end to be ready in an emergency. (Download this information as a printable brochure in English or Spanish.)

Know How to Turn Off Your Water

In the event of an earthquake or an unexpected winter freeze, you may need to turn off your water to prevent damage to your property from broken pipes.
  • Prepare in advance by locating the water main leading into your house and attach a label to it for quick identification (so that you can find it even in the dark). Turn clockwise to shut off.
  • If you can't turn the water off at the main leading into your house, shut off water at the main meter box (usually by the street), which controls the water flow to the entire property. To shut off, turn valve arrow toward the street.
  • If you can't turn off the water yourself, call MMWD's emergency line at 415-945-1500 and we will send someone to turn it off for you.
Store an Emergency Supply
One of the easiest yet most essential steps you can take to prepare for an earthquake or other disaster is to set aside an emergency water supply.
  • Keep at least a three-day supply of water for each person in your household; a five-to-seven day supply is better still. Plan for one gallon per person per day, for drinking and sanitation. Store extra water for pets and family members with special needs.
  • Tap water from MMWD can be safely stored in well-sanitized, food-grade containers such as plastic soda bottles. Avoid used milk or juice jugs and containers that will decompose or break. Seal tightly, then label and store in an easily accessible, dark, cool, dry area away from solvents and chemicals. Replace every six months. You also can purchase commercially bottled or packaged water for long-term storage.
  • Don't forget your other emergency supplies and necessities. Get a complete list at ready.gov.
Identify Other Sources of Water
If a disaster catches you without a stored supply of clean water, you can use the water in your pipes, water heater, and ice cube trays. If you're not certain about the purity of the water, filter and disinfect as described below.
  • To use the water in your pipes, let air into the plumbing by turning on the faucet in your home at the highest level. A small amount of water will trickle out. Then obtain water from the lowest faucet in the home.
  • To use the water in your water heater, close the intake valve and cut off the heater's gas or electricity supply. Open the drain at the bottom of the tank and collect the water in a clean container. You may need to turn on a hot-water faucet in the house to allow air into the tank to start the flow of water. Be sure to refill the tank before turning the gas or electricity back on.
  • Consider using water from the toilet tank or perhaps a pool or other outdoor water source for washing and cleaning purposes.
Purify Water for Drinking
In an emergency, it's possible available water sources may require additional treatment to be safe to drink.
  • If water is cloudy, filter through clean cloth or paper towels before disinfecting.
  • Disinfect water by bringing it to a rolling boil for three to five minutes, keeping in mind that some water will evaporate. Let the water cool before drinking. Boiled water will taste better if you put oxygen back into it by pouring the water back and forth between two clean containers. 
  • If you are not able to boil water, add regular household bleach (5.25% sodium hypochlorite; do not use scented, "ultra," or "color safe"). Use eight drops per gallon for clear water or 16 drops for cloudy. Mix thoroughly and let stand for 30 minutes. A slight chlorine odor should be detectable. If not, repeat the dosage and let stand an additional 15 minutes. The potency of bleach diminishes with time, so keep a sealed bottle and an eyedropper with your emergency kit.
Stay Informed When Disaster Strikes
Tune your radio to your community's emergency radio station or one of these commercial emergency broadcast stations:
  • KCBS: 740 AM
  • KGO: 810 AM
We encourage you to sign up to receive emergency alerts on your cell phone through the County of Marin's Telephone Emergency Notification System (TENS). Click the button below to register your cell phone number:
TENS alert
Want to Do More to Prepare?
For emergency preparedness information and training opportunities, visit: