GULF SHORES, Ala. — When construction begins on Little Lagoon Pass sometime next year, South Alabama researchers will employ a sophisticated piece of equipment to study sand and sediment movement in the area in and around the pass.
Dr. Scott …
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GULF SHORES, Ala. — When construction begins on Little Lagoon Pass sometime next year, South Alabama researchers will employ a sophisticated piece of equipment to study sand and sediment movement in the area in and around the pass.
Dr. Scott Douglass, a professor of civil engineering at USA, and Dr. Bret Webb, an assistant professor will conduct the study with the help of two graduate assistants.
Douglass recently met with members of the Little Lagoon Preservation Society to explain plans for the study. The study is being funded by the Alabama Department of Transportation.
“This monitoring program is going to start and its going to run for two years and will provide the data so we can evaluate the impact,” Douglass said.
A modified jetski loaded with equipment will be gathering the data.
“We will use this Jagski that Dr. Bret Webb developed,” Douglass said. “It may look like a jetski to you, but it’s not. It’s a very expensive jetski with about $100,000 or $150,000 of electronics attached.”
The shallow draft of a jetski will be perfect for working in the pass.
“He developed it because the platform, the jetski itself, can get in very shallow water and get into places boats can’t,” Douglas said. “It’s good close to bridge piers, it’s good in shallow water. It’s got the world’s best surveying equipment on it and can survey very precisely. It knows exactly where it is and can give you the depth there.”
The equipment is capable of providing data on many conditions once deployed.
“It also gives you currents underneath it,” Douglass said. “And with the big boss on the back it can also give you hydrocarbons and all kinds of water quality parameters while moving at 40 mph.
“He has literally traversed Mobile Bay for a couple of hours and sampled all the hydrocarbons in the bay in a few hours. There’s nobody else that can do that.”
While the pass will be a focal point, the entire area around the pass will also be included in the study.
“Our plan is to use that in the pass and on the shoals in the inlet lagoon, around the pass and in the sandbar outside the pass,” he said. “And on the beaches up drift and down drift for about two miles. That’s the monitoring part. We do that three times a year plus one other one that’s a floater in terms of time. Repetitively three times a year.
“To date there’s been no specific annual monitoring of the shoals and the ebb tide shoals and the littoral properties of the pass, it specifically focused on the pass.”
Earlier this year, the Alabama Department of Transportation had hoped to begin work on the project after the Shrimp Festival, but the process of getting all the permits in order has pushed that to early 2013.
“The environmental document that I’ve been harping on for six months, the final product has been given Monday,” Vince Calametti, ALDOT Division 9 Chief Engineer, said. “I anticipate that will be signed within two weeks. That was huge hurdle to get over.
“And I’ve got a Corps permit to get and a court order to get revised. With any luck we’re set up for an early December letting with a contractor starting early spring.”
When the work does finally begin, Calametti said it will take at least two years to complete.
“You have to do it in phases,” he said.
First there would be a temporary bridge, just north of the existing bridge. Access to West Beach beyond the pass will never be closed.
Of the most interesting options, one plan calls for the pass to be slighter wider with a better-defined channel. Also, there will be no bridge supports in the channel itself, but on either side of the pass instead.
A new feature, according to one of the plans, would be sediment traps that would direct the sand to common areas and make removal easier.
“We don’t think the pass will ever be maintenance free, but we hope to improve the efficiency so we don’t have to dredge as much, so that will be one of the processes we look at,” Calametti said.
When the new Little Lagoon Bridge is done, Don Powell, ALDOT 9th District preconstruction engineer said, it will have a new look as well.
“The big thing with the bridge is we’re trying to make it more aesthetic,” Powell said. “It’s just not going to be our standard girders and bridge slapped on top of it. We’re going to have some arched girders out there.”
Along with some nice touches of local wildlife and scenes incorporated into the look.
“We are currently talking about stamping some shapes into the concrete of those girders like some dolphins along the bridge abutments in approaches,” Powell said. “We had some sea oats just to make it a little more aesthetically pleasing.
“Instead of the standard barrier and hand rail it was wavy.”
The new bridge will also have pedestrian walkways on both sides of the road and walkways underneath where rip rap rocks are now.
State involvement with pass began in 1991 by homeowners west of Little Lagoon pass that said they were experiencing beach erosion near their properties because of the jetties at the pass. After a while, the homeowners dropped out of the lawsuit and it was taken up by the LLPS.
The case made it all the way to the Alabama Supreme which ruled the Alabama Department of Transportation had to keep the pass dredged to allow water to flow freely in and out of Little Lagoon.