New Science Article Reveals Human Activity Has Harmed Natural Processes Along Mississippi Delta

Note to Editors: A video about Colorado State Professor Chester Watson’s research can be found at

Human activity has hurt the interactions of the natural processes that formed the Mississippi Delta – changes that could cause even more damage and loss of human life when another intense hurricane hits the U.S. coastline, according to a new Science magazine article co-authored by Colorado State University Civil Engineering Professor Chester Watson as part of his participation on a national panel.

Watson is the only river engineer – and the only Colorado representative – on a national panel of biologists and other scientists that has recommended major improvements to Louisiana’s devastated marshlands in the wake of 2005 Hurricanes Katrina and Rita.

Watson, a Louisiana native, has spent decades as a civil engineer analyzing the stability of river channels, particularly the Mississippi River.

In the Science paper, the panel recommends reconnecting the river to the deltaic plain, using dredged sediments to create and restore wetlands, restoring barrier islands by pumping offshore sands and restoring hydrological processes by removing spoil banks, backfilling canals and protecting interior shorelines against erosion.

The independent group of scientists received logistical support from the National Research Council and financial support from the U.S. Army Corps of Engineers. The group issued its first report in 2006 for use by government officials and others.

The group concluded that restoring the coastal ecosystems would help lessen the impact of hurricane damage along Louisiana’s coast. Over the years, human activity such as building levees and oil and gas exploration has decreased fresh water and sediment flow in marsh areas, reducing plant life and allowing sediment to wash away.

That plant life is critical to the health of coastal Louisiana, which is home to 70 percent of the Mississippi River Valley’s migratory waterfowl and supplies the United States with 27 percent of its oil. The abundance of vegetation and decreased depth of water in the marsh can also mean a reduction in the height of a wall of water when a hurricane strikes.

"We need to resupply the marshes with fresh water and sediment," said Watson, who has served for several years on the National Technical Review Committee during the Louisiana Coastal Area Ecosystem Restoration Study. "The information we’ve provided in our latest report should provide local, state and federal government leaders with options to maximize environmental benefits while minimizing economic costs."

One of the panel’s key recommendations is to integrate planning and investment and management decisions regarding ecosystem management and restoration, flood protection and navigation along the Louisiana coast.

The Gulf of Mexico Energy Security Act, signed into law in December 2006, provides Louisiana and other Gulf Coast states 37 percent of revenue from newly opened oil and gas tracts. Louisiana has constitutionally dedicated these funds to coastal restoration and protection.  The funding provides significant resources toward the goal of enhancing the delta and also challenges engineers and scientists to minimize conflicts and maximize synergies in achieving this goal.

Even if improvements are eventually made, it may be years before the rivers reveal whether those changes have worked, Watson said.

"We’re still seeing the effects of things we’ve done to the Mississippi River 75 years ago," Watson said. "We really won’t know for 25 or 30 years how the natural system is going to adapt to what we construct today."

Watson obtained his doctorate from Colorado State University. Prior to joining Colorado State as a civil engineering professor in 1990, he worked as a water engineer in private industry, most recently as principal investigator of Cottonwood Research LLC in Fort Collins.

Cottonwood Research LLC is continuing research into aspects of Mississippi Deltaic Plain restoration through a research grant from University of Nottingham.

"My involvement will be to analyze how much sediment will be needed to rebuild the marshes and how moving sediment along the delta will affect the natural environment," Watson said.