During El Niño, some coastlines and river valleys get repeated heavy rain. Water in the street becomes water in the house when gutters are blocked, the ground is already soaked, or a drain cannot keep up.

Walk the outside of the house

• Clear gutters, downspouts, and the ground drains they empty into.
• Make sure soil and paving slope away from the foundation, not toward it.
• Move important papers, photos, and electronics off the floor and out of the basement.
• Find out if your home sits in a flood zone. In the United States, flood maps are published by FEMA. Other countries keep their own hazard maps with the local water or civil-defense office.

If water is likely to reach the door

Sandbags and door barriers can deflect shallow water for a while. They will not hold back deep, fast floodwater, and they do not replace leaving if officials say to evacuate. A utility pump can help with water that has already entered a garage or basement, but only if you can run it safely and the electricity is still on, or you have a rated outdoor power source.

Never walk or drive through floodwater. Six inches of moving water can knock a person down. A foot of water can float a car. The road underneath may be gone, and the water may hide a live electrical wire.

Insurance and the shutoffs

Standard home insurance often does not cover flood damage. In the United States, a National Flood Insurance Program policy usually has a waiting period, so buying it after the river is already rising is too late. Check the rule where you live before the season, not during it.

Show every adult how to switch off electricity at the breaker and how to close the gas valve if you smell gas or officials tell you to. If water is already around the panel, stay away and call the utility.