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This is a portion of a Fisk Map and it was created by Harold N. Fisk, a geologist and cartographer, in 1944 as part of his report Geological Investigation of the Alluvial Valley of the Lower Mississippi River for the U.S. Army Corps of Engineers. This map illustrates the historical meandering paths of the lower Mississippi River over a span of years, showing how the river's channel has shifted within its broad alluvial valley or "meander belt."
Each color represents a span of time and the locations of the Mississippi River channel. Without armoring, the River is a constantly meandering force capable of:
- Cutting a new channel
- Breaching a levee system
- Destroying property and threatening populations
- Interrupting navigation and commerce
- Disrupting agricultural production
- Endangering natural habitats
The Solution
Revetment efforts on the Mississippi River began in earnest in the early 20th century following devastating floods in the 1920s and 1930s. The MSU was established to lay interlocking concrete mats—each about 15 feet wide and 100 feet long—along vulnerable riverbanks to stabilize sediment and reduce scour.
Over decades, this manual process has protected critical navigation channels but relies on labor-intensive methods prone to hazards like heavy machinery operation and river currents. The Armor One project addresses these limitations through technological upgrades.
Laying mattresses traces it's roots to 16th-century Europe, particularly the Netherlands, where hydraulic engineering was critical for managing floods, canals, and dikes in a low-lying, waterlogged landscape. They were documented as early as the 1500s in Dutch river and coastal works,
Early mats were constructed of willow or lumber framework mattresses that were wired together to form protective structures that were then placed on a graded slope.
Mattresses were backfilled with silt and armored with rock. ACM was apparently invented and patented in 1914/1916. MVK sank the first ACM in 1917. It's configuration and placement methods were continually modified until the 1940's.
The organized high productive method that is used today was "put together" right after WWII. The mat boat the Vicksburg District had until the '90's was actually constructed in 1926. After the consolidation, Vicksburg received Memphis District's mat boat and it's keel was laid in 1948.
A stable channel is more efficient in moving high river stages while also reducing bank caving. As a result, levees, which are critical to the protection of a city such as New Orleans are far less likely to be compromised when they are most needed.
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