Funneling out debris

Published 12:00 am Wednesday, February 24, 2010



LAPLACE – St. John Parish work crews have begun the large-scale task of clearing a decade worth of broken trees, branches, garbage and other foreign objects from the parish’s intricate web of drainage canals – an effort parish administrators sa, will resolve a multitude of flooding problems that repeatedly affect several neighborhoods.

The bulk of the work has focused on several large outlet canals on the north side of Interstate 10 in protected wetland areas. The canals, which connect to the parish’s system of residential drainage pipes and ditches, send rainwater from neighborhoods into the Reserve Relief Canal that drains into lakes Pontchartrain and Maurepas.

“The best way to look at it is to compare our drainage system to a funnel,” said St. John acting Chief Administrative Officer Buddy Boe. “The area south of I-10 – LaPlace, Reserve, Garyville – is the top of the funnel and these canals act as the spout. If the spout is clogged, there is no way for the water in the top to get out. Clearing these canals will influence water flow out of inhabited areas and prevent all of our reoccurring flooding problems.”

Work began late last month with the clearing of the half-mile long Vicknair canal, which drains the Cambridge and old Riverlands neighborhoods of LaPlace. A one-man crew operating a rented excavator floating on pontoons spent four days clearing broken branches, fallen trees, discarded tires and a host of other foreign debris that has kept the canal clogged.

“Anything that won’t naturally break down is being pulled out of the area,” said St. John Capital Projects Administrator Mike Carmouche. “Natural vegetation is dropped along the banks of the canal an act as a ‘spoil bank,’ which keeps water from staying stagnant and further influenced water flow out.”

Carmouche said the excavator is merely clearing debris and not engaging in further dredging of any canals. He said simply clearing debris has already increased water flow in the drainage system.

“Some canals are showing at least a three inch decrease in water level,” Carmouche said. The next canal scheduled for work is the Ridgefield canal, which, Boe said, drains the heart of LaPlace from Riverlands to Belle Terre. He said the Ridgefield canal, the longest and widest, is in the worst condition of all east bank canals.

“The canal is so bad that debris and other sediment has created dams that keep the water from going anywhere,” Carmouche said. “Once this one is cleared out, we will see a tremendous difference.”

Boe said the buggy is on loan with the parish on a $33,000 month long lease. He said administration is surveying the work to determine how many more months might be needed to complete the clearing.

In order for the parish to begin work on the canals, which run through protected wetlands, Boe said the parish is required to secure individual permits from the Army Corps of Engineers for each canal that requires work. He said the parish already secured permits for three of the seven, but Boe said administrators are looking into a general use permit that would cover all canals on the east and west banks of the parish.

“The parish had a 10-year general use permit from the Corps that was allowed to expire in 2003,” Boe said. “We are looking to get at least a five-year permit so that we can regularly continue clearing the canals. We want to get into a situation where when we are in hurricane preparedness mode we can just go in and do a complete sweep of all of our canals to make sure nothing is clogging the system.”