Prehistoric Rivers Hope for Future

Prehistoric rivers 1,000 feet beneath metropolitan San Diego could provide sorely needed water early in the next century, according to researchers.

The deep ribbons of porous rocks were once drilled, but after San Diego began importing water from the Colorado River in 1946, they were largely forgotten.

Now, geologists are re-examining the underground river formation to learn whether it can provide water to the thirsty region.

The San Diego formation holds more water than the county uses in a year. But no one knows how much it would cost to pump and treat it.