Swimming pools are good to have, generally, and are handy for keeping water on hand but most home pools are relatively small.

A pool 30' by 20' by 5' is about 22,500 gallons. Sounds like a lot until you figure a 1-1/2" hose line eats up 90 to 120 gallons a minute. Giving yourself a safety factor figure 120gpm, or 2 gallons a second.

Out of that pool you are only going to get 187.5 minutes, 3 hours and 7.5 minutes of water at that rate. And that is just one hose line. Use a second line or run a roof watering system on it and it won't last long. A fire may be dropping large embers on your house for a day or more before the fire gets to you.

You may be able to husband your water supply by using lower pressures on your pumps and/or smaller lines while your just smothering sparks. You can also make every gallon work harder for you by using chemical additives, like class-A foam or gel to cover your exposures, but once the water is gone your done.

Plan well. Know how much water you have on hand and how much your pumping systems consume per minute.