There is an intense effort underway to stop the progression of saltwater moving from the Gulf of Mexico into the drought-stricken Mississippi River, in the U.S. state of Louisiana.

The saltwater intrusion unsettling for nearly one million people who depend on the river for drinking water – including New Orleans and its French Quarter – a popular tourist destination.

The impact on the area’s drinking water will likely continue for weeks – if not months – unless there is a dramatic amount of rainfall upriver, and forecasters say that’s not expected.

An environmental action plan is underway with U.S. government engineers working to increase the height of an underwater levee/sill and acquiring barges to transport fresh water to treatment plants, reducing salinity to safe driving levels.

Experts warn the demand for fresh water could reach 36 million gallons per day to support the larger communities upstream.

Thousands of residents living near the mouth of the river have been relying on bottled water since June.

There are also significant health risks involved, especially for pregnant women and those with heart, kidney and liver issues.

Agencies.