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Fig. 10
Lock and dam # 3 in the Red River
Engineers, Vicksburg District in AD 1982. L and D No. 4 was designed and built
by a consulting firm (Sverdrup Corp., Maryland Heights, Mo.) while the Vicksburg
District simultaneously built L and D No. 5. L and D No. 4 was built between two
horseshoe bends and is located about 50 miles downstream of Shreveport, Loui-
siana. L and D No. 5 is located in the town of Caspiana near Shreveport and
elevates the river to its last 120 feet, passing the design tow of six barges and tug in
approximately 25 min. Each dam maintains the required minimum pool elevation
during low water periods and is designed to pass the 100-year flood level (Combs
et al. 1994 ).
The Corps of Engineers completed the Red River Waterway Project from the
Mississippi River to Shreveport in January AD 1995. This navigation project was
the last of the Corps of Engineers' great western rivers projects. In AD 2000, the
waterway was renamed and dedicated to Louisiana Senator J. Bennett Johnston.
The lower reaches of the Red River are known as a high-energy system. Fre-
quently shifting sandbars and caving banks contribute to the large amount of
suspended sediment load. During a single high-water event, a lateral migration of
several hundred feet of bank line is not uncommon (Pinkard and Steward 2001 ).
Channel straightening was a major part of the modifications that were necessary
to make the river navigable. In order to achieve a stable navigation, numerous
channel cuts were made across bendway necks, resulting in a shorter, straighter
river stretch. In total, 50 miles (18%) of the 280 miles of the Red River were
removed by this process (Combs et al. 1994 ). In the larger (1 mile+) pilot channels,
non-overtopping dams diverted the flow into the new course. In shorter bendways,
low stone enclosures allowed for overtopping during high flow conditions in order
to divert some of the flow of the river, allowing for alternative flow paths. These
flow paths also promoted sediment deposition to areas accessible to maintenance
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