rain water harvesting

I think rainwater harvesting is an amazing way to harness such a resource. I was just writing a bit for a assignment for a class at school on the worlds water problems. I've seen and read about people implementing rain water catchment systems on their personal homes and small scale situations to decrease their need for pumping in water. However it got me thinking about industry and large scale operations. What if factories used rain catchment, this would reduce the need for them to pump in large amounts of water as well, or what if whole cities or towns came to do so. I know in places like Santa Fe New Mexico they do such things but the water is only used for gardening. Rain water can be used to bath in, clean clothes, water vegetables, drink if filtered, and wash dishes. Is there a larger movement to implement the catchment and use of rain water?

I was also thinking if rainwater catchment did go large scale and large amounts of rainwater were being captured, what kind of environmental impacts do you think this would cause?

Rainwater capture in the soil could cause dry rivers to flow again.

reference:  "Rainwater Harvesting for Drylands and Beyond" by Brad Lancaster

http://www.harvestingrainwater.com/

http://www.youtube.com/watch?v=2iQ-FBAmvBw

Yeah, there really seems to be a bit of a stigma against rainwater here.  Most of the time tanks are just connected to toilet flushing and laundry.  I guess you can do those two without a pump which makes it more low tech, which is a good thing.

I've just set up my house for rainwater throughout.  It is quite costly when you consider the need for a pump, extra water pipes, etc.  Water is very cheap to buy from the mains.

On the factory scale the amount they could capture is often so minimal compared to usage that it hardly seems worth it.  Perhaps with better water re-use techniques, this could become a reality (which would also cut down the amount of wastewater to be disposed of).

I like Brad Lancaster's stuff because it's all low tech and accessible.

I harvest rainwater for gardening.  In our climate (wet winters / dry summers) it is a no-brainer, because we are in a rural area with no water system and very limited groundwater.  Our well will supply our household needs, but not our irrigation needs.

One of the biggest obstacles to rainwater harvesting is the legislation in some jurisdictions.  Where I live, government encourages rainwater harvesting, but in many places it it illegal.

Industrial or commercial use of rainwater is problematic, and it is no doubt those situations that have prompted restrictive laws.  A factory that used rainwater as a coolant that is boiled off into steam, for example, would be in effect diverting all that water away from its natural watershed, causing ecological damage.

Household or irrigation uses put the water back into the ground where it would have gone anyway, so there is no ecological harm other than the timing (the rain enters the ground in the summer when I water the garden instead of in the winter when it fell).

I find these replies very interesting. Thanks.

I used to work at a meat processing plant that had huge rainwater tanks on all of its extensive buildings. This water was used and re-used many times. Every building with a solid roof should have rainwater storage of some kind. I know Paul advocates putting the water straight into the soil, but you can't drink, bathe or wash your clothes in water in the soil. Every new building in Australia has rainwater tanks, not barrels. We're talking 1000s of Litres storage not just a 55 gallon drum.
The house I live in has a 20000L tank that stores all the water from our house, the garage and stable roofs. You can always direct the overflow of the tank to a swale or whatever you have at home.