Safety question regarding electricity during a hurricane

October 7, 2016 1:50 PM

We recently moved to South Carolina and are on the very edge of hurricane Matthew's path, but are close enough to a marsh that we might be impacted by some flooding. This an older home that has some electrical outlets located on the floor and at the bottom of the walls. At what point should I cut power at the main breaker? The ground floor is 26" above ground and we have no basement. Thank you!
posted by wensink to Home & Garden (4 answers total)

You might want to take a close look at where the circuit breaker itself is. If you're going to touch the circuit breaker, you should do it before you would have to stand in water to reach it (you're safer leaving it alone than deliberately mixing water and electricity). That said, while I've never dealt with significant flooding, I always lost power during storms long before the strongest winds and heaviest rainfall, so the decision may be made for you anyway.
posted by ddbeck at 2:22 PM on October 7, 2016

Cheers. We're not expected to see any high winds so power *should* remain on. I was just trying to get a sense of how proactive I should be in terms of cutting the main breaker myself as we are going to hunker down on the second floor should any flooding occur.
posted by wensink at 2:35 PM on October 7, 2016

I don't know the answer, but having read ddbeck's comment, I have some related questions. (If this is breaking ask.mefi rules, please accept my apology and flag it for deletion.)

If you lose power and the house floods while the power is out, should you flip the main breaker to off? Even if it means standing in water to do this, i.e., risk the power coming on while your in the process? After the flood, how do you know when it's dry enough to restore power to a previously flooded room?

Best wishes for making it through this dry and unscathed.
posted by she's not there at 3:41 PM on October 7, 2016

I'm no expert or anything, but to give you some answer to work with: I'd say cut power as soon as water is "within reach" of any outlets. So perhaps when there is about a foot of water outside (still a foot below your floors, yes?).

If the circuit breaker box is high enough and there is no chance water will reach it or the main feed to it, you could possibly get by with only turning off the circuits that are powering outlets on the first floor. Or perhaps shut off all but one or two circuits you are sure are only on the top floor.

I don't know enough to even take a reasonable guess at she's not there's questions, though, I'm afraid. When in doubt, choose the safer option. I did find a few decent-looking resources with a quick search: 4 Rules for Electrical Safety After a Flood and Electricity Safety During a Flood. To answer the "when to restore power" question, the first link gives a reasonable answer: "Once you've replaced every electrical anything that was underwater." A circuit that was underwater could still have a short or other issue even after everything has dried.
posted by whatnotever at 7:38 PM on October 8, 2016