Contact Pacific Gas & Electric (PG&E) for information - 1800-743-5000.
If you suspect a gas leak (smell in the air, hissing noise or visibly broken gas lines), immediately get out of the area (go outside if you are in a building) and call 911 (or 650-355-4151 if on a cell phone) to report the incident to the police who will dispatch someone to come to the site to inspect and fix the potential gas leak.
Do not attempt to fix the gas leak yourself. Do not do anything that could ignite the gas in the air (light a match, smoke a cigarette, turn on electrical appliances or do anything else that could create a spark). Use only flashlights.
If you discover bad tasting/looking water, please call the North Coast County Water District at (650) 355-3462 during normal business hours. If after normal business hours, contact Police Department non-emergency line at (650) 738-7314 to report the bad tasting/looking water.
In the meantime, exercise caution in using water you suspect is contaminated by drinking/cooking with bottled water or boiling tap water (and straining with cloth if sediment is visible).
For more information on drinking water in Pacifica, visit the below website for the North Coast County Water District.