River sediment is creating new landforms on Louisiana's coastline.
Louisiana’s coastline is retreating. Over the next 50 years, scientists expect the Mississippi Delta Plain—a lobe-shaped arc of coastal land that borders the Gulf of Mexico—will lose roughly 3,000 square miles of land. But while portions of the delta plain are disappearing, new land is actually forming in a swampy area about one hundred miles southwest of New Orleans. The Atchafalaya and Wax Lake Outlet deltas have been growing southward by about one square mile per year since the early 1970s. Both deltas are being built by sediment carried by the Atchafalaya River, a distributary of the Mississippi River. The sediment settles into shallow waters and gives rise to sandbars that emerge from the sea in striking fan shapes that can be seen from space. Since 1984, USGS-NASA Landsat satellites have captured images that chronicle the growth of the two deltas. Watch the video to see a time-lapse of their evolution.