How Saltwater Is Threatening 500 Million People's Fresh Water

Ever turn on your faucet expecting fresh water but get something that tastes like ocean? That nightmare's becoming reality for millions of coastal folks worldwide. Saltwater’s sneaking underground into drinking supplies, and honestly, it's getting pretty bad.

This underground invasion hits three out of four coastal areas. By 2100, we're talking about massive populations left without safe water. The really scary part? Once salt gets into underground water, flushing it out takes forever—like decades or centuries.

Underground Tug-of-War

Picture what's happening way down below coastal towns. Fresh water flows toward the ocean while heavy saltwater tries pushing inland underground. This balancing act worked fine for thousands of years until humans started messing with it.

Holly Michael from Delaware explains it perfectly: "It's a balance between the land and the sea. But if you take away some of that freshwater by pumping it out, then that upsets the balance and the saltwater starts to move inland."