For months, saltwater from the Gulf of Mexico has crept up the Mississippi River, contaminating the area’s water supply and putting residents of Louisiana’s Plaquemines Parish on the front lines of a slowly unfolding environmental disaster. Read more:For months now, saltwater from the Gulf of Mexico has crept as far as 70 miles up the Mississippi River, contaminating the area’s freshwater supply. Millions of Americans draw their drinking water from the Mississippi River, including around 1 million people living in and around New Orleans. In late September, President Biden declared an emergency for the region, as officials at every level of government worked to prepare for the possibility that the saltwater could reach this major American city. Meanwhile, residents of southern Louisiana’s Plaquemines Parish have been without reliable drinking water since at least June. The parish is located where the river empties into the gulf, putting residents on the front lines of this slowly unfolding environmental disaster.  Climate reporter Brady Dennis traveled to Plaquemines Parish this month to see how residents have been coping. He finds that many of them feel forgotten, even as help is now on the way.