Technicians Calvin Vick (left) and John Massey
measure switchgrass stem density at Little Topashaw Creek in Mississippi.
Click the image for more information about it.
story to find out more.
Creek That Could Help Repair Waterways
By Luis Pons
May 3, 2004
It may not be among the great rivers, but
Little Topashaw Creek in north-central Mississippi is vital to
Agricultural Research Service scientists
seeking ways to best repair damaged waterways.
The 10-mile-long creek--which, when swelled, can pack a wallop within its
curving, 20-foot-high banks--is one of thousands of U.S. waterways that have
endured accelerated erosion due to neglect, poor management practices and
This situation led ARS hydraulic engineer Doug Shields and his colleagues at
the agency's National
Sedimentation Laboratory in Oxford, Miss., to launch the
Creek Stream Corridor Rehabilitation Project, which turned a two-mile
stretch of the creek into a research site.
Controlling streambank erosion traditionally requires costly stone or
concrete structures. According to Shields, who is in the lab's
Water Quality and
Ecological Processes Research Unit, they're evaluating tools such as large
woody debris structures, willow cuttings, switchgrass hedges and submersible
pumps as cost-effective ways of stabilizing streambanks and making up for past
The large woody debris structures--uprooted trees stacked in crossing layers
and anchored to the streambed with steel cables--can replicate an essential
component of stream aquatic habitat, as well as reduce sediment transport. They
cost 20 to 50 percent of the price of stone bank protection structures.
Meanwhile, Shields and University of
Memphis wetland plant physiologist Reza Pezeshki are studying revegetation
of eroded riparian streambanks by planting soaked dormant black willow
(Salix nigra) cuttings, or posts. Soaking seems to significantly enhance
the posts' ability to take root and survive during the first year. Soaked posts
survived at a rate of 64 percent, while unsoaked posts survived at a 53 percent
more about this research in the May issue of Agricultural Research
ARS is the U.S. Department of
Agriculture's chief scientific research agency.