Obviously climate change is contributing to the droughts that have caused this problem, but it's also exacerbated by much more tangible climate change: we changed the river climate by digging it deeper so it could fit bigger boats, which makes it easier for saltwater to move upriver. When the Army builds a barrier to try to delay the saltwater, they have to put a big hole in it so the boats can still get through.

More details: https://sph.tulane.edu/5-things-know-about-saltwater-intrusi...