Measuring Subsidence in the Atchafalaya Basin

As the Atchafalaya River spreads out through the Basin, the waters slow down, and the sediment falls to the river and lakebottoms. Over time, that sediment can build up, eventually choking the river or permanently closing the lake. Or, as more and more sediment piles up, it compacts, sinking deeper during a process known as subsidence. The twin processes of sediment deposition and subsidence is very important to the health of the Atchafalaya Basin. USGS has a network of sensors throughout the Basin that monitor subsidence.

In late 2015/early 2016 unusually large rainfall in the Upper Mississippi River Valley led to significant flooding in Arkansas, Illinois, Louisiana, Mississippi, Missouri, and Tennessee. USGS crews responded to the flooding by collecting streamflow and water quality information and providing it to emergency responders.