Page 14 - July August 2017 Vol 35 No 2
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can form in a single rain event. A blocked canals of west Tennessee is not an easy request that the WTRBA come and review
river loses the power to move sediment job but the WTRBA has a team of skilled problems with flooding and erosion. Some
and the channel begins to fill. These block- operators with a passion for maintaining problems are minor and can be solved
ages must be removed. Many of the work the rivers. with simple adjustments like adding a
areas are miles from roads or bridges. pipe to a downspout. Other problems
Access was a real issue until the Executive The amphibious excavator is not the require complex engineering and expen-
Director of the WTRBA, David Salyers, only tool for protecting public interests. sive construction. These problems end up
found equipment used in the marshlands WTRBA provides maintenance duties for at the WTRBA because it is ideally suited
of Louisiana. In a matter of months, a more than 120 flood and sediment control to solve big problems. Take as an example,
new type of excavator was delivered to structures (i.e. lakes) that were built flooding along State Route 22 in Obion
west Tennessee - a hydraulic excavator between 1972 and 1996. One hundred County. An existing stream channel had
mounted on a pair of pontoons with high and eight of the structures are regulated become filled with sediment and was no
density plastic tracks. This new machine under Safe Dams permit requirements and longer carrying flow. A rain of half an inch
had the ability to float and could move must be mowed and inspected annually. would flood over the highway and into
through the swamps of west Tennessee The benefits for public safety and stream agricultural fields to the south. Farmers
more easily than it could navigate on dry quality from these structures are easy to along the south side of the road construct-
land. Like a giant mechanical dinosaur, it overlook but the staff of the WTRBA take ed levees to protect their fields from the
crawls through muck and debris to clear pride in working in the background. In flooding. These new levees trapped flood
obstructions. The only downside is the May of 2010, west Tennessee received waters in the highway and created a dan-
speed. An amphibious excavator travelling historic rainfall ranging from 13 inches in gerous situation of standing water during
at full speed moves at an impressive 1.5 Jackson to 18 inches in Covington. Three rains and a slippery layer of mud after the
miles per hour. At the end of a workday WTRBA lakes experienced a controlled waters drained away.
the excavator is parked on a nearby stream activation of the emergency spillway that
bank and the crew will pick up at the required major repairs. One lake provided The WTRBA completed a hydraulic
same spot the next day. This saves hours protection from two private dam failures study and demonstrated the most reliable
of travel time but requires transportation upstream which would have been cata- solution to the problem. Within a year
to get to the machine when it is parked in strophic for roads and houses downstream. the project was designed, permitted, and
remote locations. A modified airboat with constructed to fast-track public safety.
a carbon fiber aircraft propeller and a V-8 Public service for the WTRBA doesn’t Technical assistance often leads to special
engine does the job nicely. Operating an stop at maintenance activities. Techni- projects. These projects are construction
amphibious excavator and airboat in the cal assistance is also a large part of the activities ranging from bank stabilizations,
program. Landowners, municipalities, grade control, and stream restorations.
and even other government agencies often
View online at tnpublicworks.com 13
