Mississippi watershed and the role of wetlands in flood management

Abstract

The Mississippi River is the longest river in North America and the fourth longest in the world. The Mississippi-Ohio-Missouri (MOM) watershed, including the Arkansas River, covers some 4.76 million square kilometers encompassing approximately 40% of the conterminous United States of America. The water- shed comprises several major sub-catchments and ultimately discharges into the Gulf of Mexico through the Mississippi Deltaic Plan (MDP). Within the last 100 years, the MDP has experienced relative sea level rise as the surface area has been reduced and wetlands lost. Much of the wetland loss has been associated with wider activities across the watershed that have reduced sediment input to the river and consequently to the wetlands. This, combined with the likely increased intensity of tropical storms as a result of climate change and the ongoing loss of wetlands which offer protection from coastal storm surges, will increase the vulnerability to flooding of near coastal human settlements and infrastructure.