Three Rivers Study, Southeast Arkansas

Published Sept. 17, 2013

A “new start” and funding of $100,000 is needed to complete a 905(b) reconnaissance study of the water resource problems in south-east Arkansas where the Arkansas, Mississippi, and White Rivers converge. The study will determine potential solutions, scope, further federal participation, and identify nonfederal sponsors to provide a comprehensive watershed analysis of basin conditions and alternatives. The study is authorized by Section 216 of the Rivers and Harbors Act of 1970.

The study is needed to investigate serious hydrologic and hydraulic problems that are threatening navigation, aquatic ecosystem habitat, Ark/White Cutoff Structure, recreation, flood damage reduction and watershed protection. Long-term solutions were evaluated in a previous Ark/

White Cutoff Study to address the navigation reliability problem, but the National Economic Development alternative plan was not environmentally acceptable because extensions of levees would require use of U. S. Fish and Wildlife Service land that was deemed incompatible with the refuge purpose. Therefore, the study result was to continue maintaining existing structures and construct new structures to maintain navigation reliability – a band-aid approach.

However, the Ark/White Cutoff Study confirmed that the problems and solutions are interconnected and interdependent throughout the entire region. The study location is at the confluence of the Mississippi, White, and Arkansas Rivers in Desha and Arkansas counties, Ark.

The study area is in three Corps districts (Little Rock, Memphis, and Vicksburg) and two Corps divisions (Southwestern and Mississippi Valley). This area is the starting point for the McClellan-Kerr Arkansas River Navigation System that begins at the mouth of the White River and runs 445 navigable miles to Catoosa, Oklahoma. The watershed of these three rivers is home to the White River National Wildlife Refuge and more than 100,000 acres of critical bottomland hardwoods.

This is the largest stand of bottomland hardwoods on any tributary to the Mississippi River. The significant erosion is causing the loss of large areas of bottomland hardwoods. The refuge and the surrounding area are habitat for numerous threatened and endangered species, including the Bald Eagle, Interior Least Tern, Pallid Sturgeon, and Ivory-billed Woodpecker.

The erosion in the watershed is also a serious threat to navigation, recreation, and flood risk management. The Montgomery Point Lock and Dam, located on the Arkansas River, became operational in fiscal year 05. The dam, located at navigation mile 0.5, is at risk of the severe erosion that is continually under repair between navigation miles 3 and 8 on the White River. If a full breach were to occur, navigation could be impacted for more than 100 days, at a cost of nearly $300 million and thousands of acres of wetlands and pristine hardwoods would be lost. Possible solutions include passive weirs or gated structure that would regulate the flow of water and reduce erosive action. The State of Arkansas understands the cost-sharing requirements and Arkansas Waterways Commission would be the local sponsor.