Rather than wait for a household emergency, take time to understand the inner workings of your home’s utility infrastructure.
Start by ensuring the whole family knows the location of your main water shut-off valve, so quick action can be taken to minimize damage in the event of a major leak. From there, you can trace the path of your water supply pipes to each faucet.
Next, locate your main electrical panel. It should have all room lighting and appliance circuits labelled. If it doesn’t, you should have it done, in order to avoid difficulty in identifying a circuit should one fail, overload or need to be disconnected.
After the power, consider your heating and air conditioning. If they are delivered via forced air, then ducts are easily traced from the source unit to the supply grills. Generally speaking, most electrical wiring is threaded through and along wall studs and support beams, terminating at wall outlets, ceiling fixtures and major appliances, whereas plumbing, heating and AC tends to be channeled between structural framework.