A model of flood management in the U.S., now forgotten

In the 20th century, floods were a major problem in the U.S. A now-forgotten model of the Mississippi River Basin, built to better understand flood management, is remembered.

We've written much about water scarcity here on SmartPlanet, but just as much a problem is the destruction that comes from a major flood.

In a lovely, detailed report in the journal PlacesKristi Dykema Cheramie writes that the U.S. was once under siege from its own lifeblood: the Mississippi River.

In the early 20th century, the Mississippi River Basin was inundated with the worst flooding in American history, prompting Congress to legislate a plan to control its mighty waters, tapping the Army Corps of Engineers and dozens of dams, locks, levees and runoff channels.

In doing so, Congress effectively made flood control a federal responsibility, with the Army Corps of Engineers as the first lines of defense. "In essence, the act was driven by commerce but framed as national defense," Cheramie writes.

But as any scientist knows, you must first understand the problem you're trying to solve -- and it was quickly apparent that America didn't know much at all about its largest river.

Enter district engineer Eugene Reybold, whose concern about localized solutions --  which may solve the problem in one area of the river but exacerbate it downstream -- led him to develop a large-scale hydraulic model that would allow the engineers to observe how weather effects and proposed control measures interact over time.

Cheramie writes that only a physical model of the region could help solve the entire problem:

Reybold understood that such a project would require a paradigm shift in the Army Corps of Engineers. His colleague John Freeman ran a small hydraulics laboratory, the Waterways Experiment Station, in Vicksburg, Mississippi, but had been denied funding for more comprehensive research. "Field experience," said Secretary of War Dwight Davis, "is undoubtedly of much greater value than laboratory experiments could possibly be."

Nevertheless, Freeman’s laboratory drew the attention of young, ambitious engineers who could see the benefit of fluid mechanics modeling. Reybold worked with the Experiment Station to construct a small section of the exceptionally steep Kanawha River as a pilot model. He knew that if he could simulate historic flood events and produce accurate flood hydrographs of the Kanawha, he could build support for a model of the entire Mississippi River Basin. Reybold’s plan worked; in 1943 the Corps of Engineers approved his proposal to build a comprehensive model.

The model -- despite being the "most complicated, expensive and time-consuming research project ever undertaken by the Corps" -- was completed in 1966 and used for two decades, preventing an estimated $65 million in damages.

But the model faced competition from mainframe computers as early as 1971, and was eventually retired from service in the 1990s.

Cheramie writes that the map demonstrated three key points about water management in the U.S.: materials, scale and scope matter.

"Although the Mississippi River Basin Model was never truly comprehensive — never fully systemic — it was nevertheless an incredible feat of design thinking," she writes.

The Scale of Nature: Modeling the Mississippi River [Design Observer]

Illustration: Arthur Gibbs Sylvester/UCSB

This post was originally published on Smartplanet.com