If PG&E shuts down power as part of its plan to prevent fires in northern California, the water will keep flowing in the Valley, thanks to Zone 7 Water Agency’s preparations.

PG&E sent out notices with May bills that stated it had formed a Public Safety Power Shutoff program that would halt power deliveries in rural areas that may be threatened by wildfires. Investigators found that last year’s fatal Camp Fire, in Butte County, was caused by sparks from PG&E equipment.

The northern California power grid is interconnected. If PG&E shuts down power in one location, other areas in northern California could be affected.

PG&E states in its May letter to customers that an area could be missing power for 24 to 48 hours after the shutoff starts, but that could stretch to five days.

One effect not mentioned in the PG&E letter is water service delivery. Pumps at Zone 7, the Valley’s water wholesaler, and at the four retailers here — Livermore, Pleasanton, DSRSD, and privately owned Cal Water — run on electricity. If the power were out, there would be no water circulating for cooking, bathing, or toilets.

But Zone 7 and the retailers are ready for such an emergency, said Zone 7 General Manager Valerie Pryor.

Zone 7 has two plants for water treatment and distribution ― one at Patterson Pass in the Altamont, and the other at Lake Del Valle. Both plants have backup generators in case power stops. Each has a three-day supply of fuel, but the agency also has contracts with other generator suppliers who can each roll out at least three days of juice.

Zone 7 staff met with the retailers on the issue, and attended the Alameda County Emergency Managers’ Association meeting. It featured a briefing on the PG&E Public Safety Power Shutoff program. PG&E staff reviewed potential power shutoff factors, and the notification system and processes. Staff has taken the information provided and is taking the necessary steps to prepare for potential outages during fire season, according to an agenda report prepared for the July 17 Zone 7 board meeting.

The letter that PG&E sent to customers notes that the utility will notify customers before the shutoff via email, phone, or social and traditional news media.

It may take 24 to 48 hours to get the power back on after a shutdown. In general, PG&E will be looking for high winds and low humidity as signs of danger that would turn land into a tinderbox.

Sacramento TV station ABC 10 reported online that its own outreach on social media showed some concerns about people’s vulnerability. The station said that many people on Facebook pointed out that warnings to medically vulnerable people are not valuable, unless they have a place outside the powerless area where they can stay.

Cities receiving the PG&E notices are “scrambling to come up with a plan to keep people safe, in case power does get cut for days at a time.”

In Manteca, which is 75 miles east of Livermore, the city plans to offer emergency charging stations in various locations, but only for medical devices. If people need a cell phone charge, they are on their own.