. >> you have to go to the arizona department of water resources and demonstrate that you have sufficient water supplies for 100 years. in order to be able to sell a new house, you have to demonstrate that you've got this water supply. >> they are also stocking up to buffer against future shortages. >> we take some of our colorado river delivered through the central arizona project, and we store it underground through storage ponds. it doesn't evaporate. it's there for the future use. >> homes in america use 27.5 billion gallons of water every day, preparing food, flushing toilets and watering lawns. >> as we see buildings go up vertically, what we're seeing is less landscaping on a per-resident basis. we're also seeing the opportunity to reuse some of the water internally. we're seeing rooftop gardens. >> there's much more consciousness in terms of individual homes. we have low-flow toilets and shower heads, desert landscaping. >> on a per-person basis, water demand is going down. new construction is more efficient than old construction. people are remodeling their homes. >> regulations

. >> you have to go to the arizona department of water resources andemonstre that you have sufficientplies for 100 years. in order to be able to sell a new house, you have to demonstrate that you've got this water supply. >> they are also stocking up to buffer against future shortages. >> we take some of our colorado river delivered through the central arizona project, and we store it underground through storage ponds. it doesn't evaporate. it's there for the future use. >> homes in america use 27.5 billion gallons of water every day, preparing food, flushing toilets and watering lawns. >> as we see buildings go up vertically, what we're seeing is less landscaping on a per-resident basis. we're also seeing the opportunity to reuse some of the water internally. we're seeing rooftop gardens. >> there's much more consciousness in terms of individual homes. we have low-flow toilets and shower heads, desert landscaping. >> on a per-person basis, water demand is going down. new construction is more efficient than old construction. people are remodeling their homes. >> regulations were adopt

. >> you have to go to the arizona department of water resources and demonstrate that you have sufficiento sell a new house, you have to demonstrate that you've got this water supply. >> they are also stocking up to buffer against future shortages. >> we take some of our colorado river delivered through the central arizona project, and we store it underground through storage ponds. it doesn't evaporate. it's there for the future use. >> homes in america use 27.5 billion gallons of water every day, preparing food, flushing toilets and watering lawns. >> as we see buildings go up vertically, what we're seeing is less landscaping on a per-resident basis. we're also seeing the opportunity to reuse some of the water internally. we're seeing rooftop gardens. >> there's much more consciousness in terms of individual homes. we have low-flow toilets and shower heads, desert landscaping. >> on a per-person basis, water demand is going down. new construction is more efficient than old construction. people are remodeling their homes. >> regulations were adopted that required golf courses to reduce th