earthquake crack on the ground

Earthquake Preparedness

Earthquake Preparedness: A Little Backstory

The Loma Prieta earthquake which struck the Bay Area on October 17, 1989, stretched local resources to the limit as San Jose Water tried to maintain and restore service to the residents in hard-hit Los Gatos. The events following the earthquake remind us that water service may be interrupted following any significant disaster. You should be prepared for such disasters and take steps to assure that an emergency supply of drinking water will be available. The Santa Clara County Department of Environmental Health Services offers the following guidelines:

How to Prepare Water

Store water in plastic containers, preferably heavy opaque plastic with tight fitting screw-on caps. Use within one year or replace. A two week supply for every family member is considered the best rule of thumb.

The water stored in water heater tanks is a good temporary source of supply. Water heater drain taps should be turned on once a month to drain rust and sediment. Be sure to turn off the gas or electricity before draining the water heater. Securely strap the water heater to a wall to prevent water loss as well as possible broken gas lines to the heater.

Water Purification Chart

Amount of Water   Amount of Bleach:    
Clear Water
Amount of Bleach:   
Cloudy Water
1 Quart2 drops4 drops
1 Gallon8 drops16 drops
5 Gallons1/2 teaspoon1 teaspoon


If there is any doubt about the quality of available water, it should be purified before use. Boil vigorously for 1 minute or use (unscented) liquid household bleach (sodium hypochlorite 5.25%) as a disinfectant. Please see attached water purification chart for details. After adding bleach, mix thoroughly and let water stand for 30 minutes before using.

If water is cloudy or contains suspended particles, strain through a coffee filter or several layers of clean cloth to remove debris before attempting disinfection.

Earthquake Preparedness List

You should be prepared to survive at least three to five days following an earthquake. The following is a partial list of things that will help.

  • Cooking utensils
  • Food for each family member. (Dehydrated camp food is light and stays fresh for many months.)
  • Sanitary wipes
  • Medical supplies (prescriptions, medication, eyeglasses, etc.)
  • Spare cash
  • Field handbook (for setting up shelters, etc.)
  • Family pictures to help authorities locate lost family members
  • Extra flashlight and batteries
  • Extra sleeping bags
  • Portable toilet
  • Plastic bags for human waste
  • Rope, plastic sheeting and duct tape for broken windows and other temporary repairs
  • Goggles and dust masks for working around glass, dust and bacteria
  • Crowbar to open jammed doors
  • One-gallon containers of water that can easily be carried if you must evacuate
  • Fire-resistant strong box for storing valuable papers
  • Fire extinguisher