The McClellan–Kerr Arkansas River Navigation System (MKARNS) was the largest civil works project undertaken by the Corps at the time. It was originally authorized by Congress as early as July 24, 1946, in that year’s Rivers and Harbors Act (it was known as the Arkansas-Verdigris Waterway prior to legislation changing its name). The plan included hydropower, flood control, recreation, and navigation from Catoosa, Okla., to the Mississippi River. Although reservoirs and other parts of the system began to be built in the 1950s, the system as a whole was formally dedicated only in 1971.
Total tonnage through the Three Rivers project area, where the Arkansas, White and Mississippi rivers approach closely to each other has grown from 1.82 million tons in 1971 to more than 9 million by 2007, according to the Corps. Top commodities moving on the system are fertilizer, iron and steel, coke and coal, farm goods, building materials, manufacturing ores and chemicals, and distillate and fuels oils.
The waterway system is a distribution hub for fertilizer to Midwestern farmers. Since 2001, fertilizer deliveries to MKARNS ports have steadily increased, despite the 2008 financial crisis. Likewise, iron and steel product movements have increased by about 2.9 percent per year since 2001, mostly serving manufacturers in Arkansas and Oklahoma. About half the outbound tonnage from the MKARNS system heads for Gulf ports for export; export soybean freight grew at an average rate of 9.8 percent from 2001 through 2014.
The system also provides flood control benefits that prevented more than $1.3 billion in damages from 1974 through 1987. More than 1 billion kilowatt hours of electricity are produced annually at half the cost of electricity produced by coal, providing competitive power costs for the region.
Other factors have contributed to regional growth. The MKARNS region boasts its own shale play, the Fayetteville Shale, a tight shale natural gas reservoir. Southwestern Energy began drilling in 2005 using hydraulic fracturing (fracking); the drilling rigs are significant consumers of diesel fuel, much of which moves by barge.
In March 2015, the Corps of Engineers redefined MKARNS from a moderate-use system to a high-use one.
If economic growth is a measure of success, then the project must be rated very successful.
As the system ages, challenges have increased. The Arkansas River’s 18 locks are all only 600 feet long. Water hyacinth has spread throughout the system and is a major nuisance. Regional interests in the region want the Arkansas River’s channels dredged to a consistent 12 feet (a depth already present in some parts of the river).
In the early 1970s, it was recognized that the White River and Arkansas River were trying to join with each other. The two rivers approach each other closely before veering off and creating an isthmus between the two and the Mississippi River. Twenty years after the opening of the system, a 10-mile-long canal was built to relieve pressure, but high water regularly stresses the existing control structures, and floods have become more frequent in recent years.
As recently as 2009, the Corps recommended “no action” on those stresses, even though maintaining and repairing the extant control structures involved increasing costs.
But after MKARNS business and waterways interests fought for a new feasibility study, it was completed and added to the 2018 Water Resources Development Act. The Corps’ Tentatively Selected Plan involves adding more containment structures and strengthening others as the most cost-effective means of maintaining the system’s integrity and preventing breaches.
The success of the MKARNS system shows not only the long-term benefits that investment in waterway infrastructure can have, but the results that can be achieved when all of a region’s stakeholders work together to promote a common vision of waterways as powering growth.