South Florida's lakes, marshes and rivers pump fresh, crystal clear water across the state like veins carry blood through the body.

But cities along South Florida's coast are running out of water as drinking wells are taken over by the sea.

Hallandale Beach has abandoned six of its eight drinking water wells because saltwater has advanced underground across two-thirds of the city.

"The saltwater line is moving west and there's very little that can be done about it," said Keith London, a city commissioner for Hallandale Beach, who has worked on water conservation and reuse for the last decade.

A wall of saltwater is inching inland into the Biscayne Aquifer — the primary source of drinking water for 4.5 million people in South Florida.

A hundred years ago, saltwater intrusion was not a problem in the area. The Everglades seemed to hold more freshwater than residents could ever use.

But then swaths of the "River of Grass" were drained through canals to clear farmland and build single family homes. Utilities have been trying to keep saltwater at bay since the 1930's. But saltwater has crept in to replace freshwater that drained out to sea.

Now, commissioner London and Hallandale Beach city staff need to secure a new source of drinking water. They are working on a deal to dig wells in West Park, another South Broward city about three miles inland. Hallandale would then pipe the fresh water back east.

The project will cost an estimated $10 million, says Earl King, Deputy Director of Hallandale Beach Utilities and Engineering. Residents will eventually pay those capital costs.

New drinking water wells are likely the cheapest alternative, London said. The city could build a reverse osmosis plant to filter out the salt, but the construction and maintenance costs would be astronomical.

"The energy needed to remove the salt would have made water cost 10 times, 100 times more than what we are paying now," London said.