Watersheds are the most basic water supply infrastructure for cities.
The most basic water softener, he said, requires the homeowner to take a number of steps to "regenerate" the unit.
Angolan government officials say there is no overnight solution to the lack of basic water and sanitation.
"The Delta provides a substantial amount of the basic water supply for 25 million people," he says.
And while the Holland Tunnel was built for cars, Mr. Daly's tunnels are for something more basic: water.
It is a worthy effort that will save lives, but not a substitute for basic water and sanitation.
In addition to basic water safety, things to watch out for are wildlife of all kinds, including rattlesnakes, poison oak and poison ivy ashore, sunburn and dehydration.
While cholera can kill its victims in a matter or hours, it is easily controlled through basic water treatment and sanitation measures.
"One out of five people in the world has no access to drinking water and 40% of the population lack basic water treatment facilities," according to Unesco.
More than a billion people lack the most basic water supply, said the study, backed by the World Health Organization and the United Nations Children's Fund.
New York in the 19th century, while primarily under the control of the Tammany Hall political machine, constructed Manhattan's basic water, sewer, fire, police, transportation, and park facilities.
