Plans in progress for agitation dredging
MORGAN CITY — Agitation dredging by dragging a metal object similar to a bulldozer blade across the bottom of waterways to stir up sediment will be the first technique used by the Morgan City Harbor and Terminal District in field trials as it attempts to find a solution to manage problematic sediment formations within the Atchafalaya River system.
The technique involving dragging the piece through the area in a process called “bottom profiling” has been shown to agitate dredged material on the bottom of waterways like the port is hoping to do, said Jonathan Hird of Moffat and Nichol, the Baton Rouge firm tasked with helping the Port of Morgan City find a way to manage its sediment problem.
It could be tested during the next regular dredging cycle if costs do not top an unspecified amount, Hird said. That dredging cycle could occur sometime in September.
The method is more cost effective and easier to complete than other strategies, too, Hird said.
“It’s quick,” he said. “It’s easy to do. We can determine if it’s going to work, if it’s not going to work. Does it need to be tweaked? It certainly is something that we could do this year and leave it on the table or scratch it off the list and move to the next.”
The method is used on the West Coast and other areas by dredge contractors after they finish their work in order to smooth the area they have just cleared of shoaling.
“Dredging contractors use it all the time, because obviously they’re paid on what the final surface elevation is,” he said. “So they’ll drag this piece of equipment (on the bottom) once they’ve finished dredging.”
While Hird said the use of a sidecaster is the best option, he said it would take time to construct the equipment needed for that method and would be more costly.
If the use of the metal structure does not work, Hird said that the use of water injection dredging, which involves the shooting of water into the material to break it up, can be used.
The third option would be the use of a sidecaster.
The plans are to survey the area before the dredging, immediately after dredging has been completed and then weekly after the dredging is complete to better understand the behavior of this sediment.
In other news, commissioners:
—Learned from port Manager of Economic Development Cindy Cutrera that the Corps has told her they need the Port of Morgan City’s 2010 year-end tonnage figures this month, rather than this December, so she said she is working to complete those figures. She said the port may “struggle” to keep its Top 100 ranking because of reductions as a result of the BP oil spill last year.
—Learned from commissioner Deborah Garber that the port has received a payment for bulkhead work at InterMoor. She also said within the next month, she will be in contact with commissioners on scheduling a budget workshop. The goal is to bring a budget to the board by the July monthly meeting.
—Learned from Executive Director Jerry Hoffpauir that all permits have been obtained to go out to bid for a contractor to construct the port’s boat dock. The project should be bid in August, Hoffpauir said.
—Learned from Phillip Chauvin of T. Baker Smith that approximately 450 feet of bulkhead has been installed at InterMoor; work will start next on the installation of a crane pad. He said a week to 10 days was lost on the project because of the high water. The port approved payment request 2 of $613,579 to Dolphin Services in Houma for work on the InterMoor bulkhead project.
—Learned from the port’s grant writer, Mike Knobloch, that the Port of Morgan City is eligible for up to $1 million in Port Security Grant funding with no match for 2011. Knobloch said he should have paperwork for the project submitted by Friday. While he was prevented by the terms of the grant from specifically outlining the purchases with the money, he said they would be security-related items.
—Renewed its policy with Paul’s Insurance Agency, but agreed to comb through and update the values of its property so they can be accurately reflected in the insurance policies.
Absent from Monday’s meeting were Commission President Raymond “Mac” Wade and commissioners Joe Jones and Greg Aucoin.