Without clean drinking water, you have about 12 hours before you start to feel dry and sluggish. 12 more, headache. 24 after that, you’ll be seeing things or have lost most critical thinking.

No matter what, I have 10 or so gallons of potable water around, and I double that during hurricane season, filling up water bottles and freezing them to get some cooling out of it as well. I learned this the hard way during the aftermath of Katrina when we had no power for two weeks and nearly ran out of drinking water.