Certainly a gas-powered pump would be a great idea if there were a swimming pool. I suspect there just isn't the water available in the mains even with an auxillary pump. A pump which could put out a nominal 3.4 gallons/second would be about $500. Then all that's needed are the pipes, hoses and sprinklers. At the heighth of a house that may be closer to 2.5 gal/sec, still a lot of water.

In my area wells are a possibility. I looked into it as a source of cool water for a form of air-conditioning. They are also allowed for watering lawns and gardens. However, there can be no, repeat no physical connection between the well and city water.

I believe the flow from wells would be limited, too.

I would think that with a pool as a resevoir the best strategy would be to have massive sprinklers on the ridge-line of the house, and start spraying outward, rather than using a lawn system and spraying inward. With a big enough pump one could move a lot of water over the house and out into the yard for a short period of time.

The water from a well could be used to refill the pool and to sprinkle the yard closer to the house. And maybe a $200 booster pump connected to city water could be filling the pool, too.

It certainly could be built with readily available materials, and not be too expensive, either.

What might be interesting is having "kits" ready, gas-powered pumps and sprinklers and rent them on an as-needed basis. Have the system put in by two people, and either overseen by them or the homeowner. You're looking at less than $1000 for a system, a bit more with the auxillary pump. And since the pumps are gas-powered, there's no need for generators and power lines.

I can imagine it wouldn't take more than one fire to pay for the material. I suspect that one system and two people for a day would be worth $4 or $5 thousand to some people. It might take a couple of systems for some larger houses. Depending upon the roofing materials, it might work to have sprinklers at the perimeter of the house spraying out, too. One has to be aware of sparks and cinders flying around.

Arf