Scientists use massive river model to fight erosion

In this March 29, 2018 photo, Rudy Simoneaux, above, engineer manager for the Louisiana Coastal Protection and Restoration Authority, and Joseph McClatchy, coastal resources program specialist, walk on a replica of the lower Mississippi River in Baton Rouge, La. The model will help experts study the river and how sediment can be used from it to fight coastal erosion. [Photo: AP/Gerald Herbert]

US Scientists working on new ways to battle the erosion that threatens Louisiana's coastline have a dramatic new tool: a massive replica of the lower Mississippi River.

The multi-million US dollar model, complete with flowing water, aims to isolate the best areas to divert nutrient-rich river water and sediment into rapidly-eroding marshes.

CRI's Yu Yang has the story.

Lake Hermitage in Louisiana is a popular destination for residents and wildlife alike.

But the fragile coastline around the old fishing village is under threat from decades of erosion while also facing rising seas from climate change.

Saltwater intrusion from the Gulf of Mexico has killed off almost all the trees in areas that were thriving decades ago.

Lifelong Louisiana resident Clay Boudreaux says he has watched the land surrounding the Lake Hermitage area where he grew up slowly disappear.

"And now here we are, fifty, sixty years later, and there's not a live oak tree back here. For five miles off the highway away from the river, that used to be fed by the river, now nothing. Nothing's alive other than the trees that we've planted in our yards."

Louisiana is estimated to have lost about 5,200 square kilometres of coastline since the 1930s.

But help may soon be on the way.

In this March 29, 2018 photo, Rudy Simoneaux, left, engineer manager for the Louisiana Coastal Protection and Restoration Authority, and Joseph McClatchy, coastal resources program specialist, walk on a portion of a replica of the lower Mississippi River in Baton Rouge, La. The model will help experts study one of the most important rivers in North America and how sediment can be used from it to fight coastal erosion. [Photo: AP/Gerald Herbert]

Scientists working to battle the erosion have a dramatic new tool - a massive replica of the lower Mississippi River.

The Louisiana State University's Center (LSU) for River Studies is home to the newly opened Lower Mississippi River Physical Model, a 10,000-square-foot reproduction of nearly 200 miles of the lower Mississippi.

The model will help experts study the river and how sediment can be used from it to fight coastal erosion.

In this March 29, 2018 photo, Rudy Simoneaux, right, engineer manager for the Louisiana Coastal Protection and Restoration Authority, and Joseph McClatchy, coastal resources program specialist, walk on a replica of the lower Mississippi River in Baton Rouge, La. The model will help experts study one of the most important rivers in North America and how sediment can be used from it to fight coastal erosion. [Photo: AP/Gerald Herbert]

LSU Professor Clint Willson heads the Center for River Studies.

"Not only can we model the flows and the river stages or the water levels in the Mississippi River, we can also model or simulate the transport or the movement of the Mississippi River sand down the river. And we can do all of that in roughly one hour to replicate one year on the river."

The model is made of high density foam panels strong enough for people to walk on.

Data about the dimensions and shape of the Mississippi River and surrounding topography were put into a computer and then used to cut the panels.

In this March 29, 2018 photo, Rudy Joseph McClatchy, coastal resources program specialist for the Louisiana Coastal Protection and Restoration Authority, points out features of a replica of the lower Mississippi River, with satellite images projected onto it from above, in Baton Rouge, La. [Photo: AP/Gerald Herbert]

Rudy Simoneaux from the Coastal Protection and Restoration Authority says the new model is already attracting worldwide attention.

"We've had folks from China. We've had folks from Bangladesh, who have a major river flooding problem in their nation, and they're looking at ways to living and working with the river."

Louisiana has developed a plan that relies in part on slicing channels or diversions at various locations into the levees that keep the Mississippi River in its course.

Officials are hopeful that lessons learned at the new center can be shared with other countries and regions struggling with similar problems.