. >> the central arizona project was constructed in the 1970s and '80s. the massive system brings the water to the population centers of phoenix and tucson. >> it cost over $4 billion to build. there was a 300-mile- long excavation, several tunnels bored through mountains, siphons going under rivers. it's an engineering marvel. and you can see it from outer space. >> on average, more than 5 trillion gallons flow through the canal every year. >> what we're looking at behind me here is a map board of the system itself. it's 336 miles long, controlled by two dispatchers that are sitting behind us here. >> we have 15 pumping stations along our 300-plus-mile canal. we have to basically pump the water uphill and then let it flow by gravity over some period of miles. >> so all these values that you're looking at are in cfs, cubic feet per second. so as you can see here, this pumping plant's doing 2,086. starts at lake havasu, goes all the way down through some mountains, underneath some riverbeds, and then it eventually ends up in tucson. >> from 1985 to 2010, c

. >> the central arizona project was constructed in the 1970s and '80s.on centers of phoenix and tucson. >> it cost over $4 billion to build. there was a 300-mile- long excavation, several tunnels bored through mountains, siphons going under rivers. it's an engineering marvel. and you can see it from outer space. >> on average, more than 5 trillion gallons flow through the canal every year. >> what we're looking at behind me here is a map board of the system itself. it's 336 miles long, controlled by two dispatchers that are sitting behind us here. >> we have 15 pumping stations along our 300-plus-mile canal. we have to basically pump the water uphill and then let it flow by gravity over some period of miles. >> so all these values that you're looking at are in cfs, cubic feet per second. so as you can see here, this pumping plant's doing 2,086. starts at lake havasu, goes all the way down through some mountains, underneath some riverbeds, and then it eventually ends up in tucson. >> from 1985 to 2010, central arizona project generated $1 trillion with a

. >> the central arizona project was constructed in the 1970s and '80s.ve system brings the water to the population centers of phoenix and tucson. >> it cost over $4 billion to build. there was a 300-mile- long excavation, several tunnels bored through mountains, siphons going under rivers. and you can see itg marvel. from outer space. >> on average, more than 5 trillion gallons flow through the canal every year. >> what we're looking at behind me here is a map board of the system itself. it's 336 miles long, controlled by two dispatchers that are sitting behind us here. >> we have 15 pumping stations along our 300-plus-mile canal. we have to basically pump the water uphill and then let it flow by gravity over some period of miles. >> so all these values that you're looking at are in cfs, cubic feet per second. so as you can see here, this pumping plant's doing 2,086. starts at lake havasu, goes all the way down through some mountains, underneath some riverbeds, and then it eventually ends up in tucson. >> from 1985 to 2010, central arizona project genera