The parish presidents of East Baton Rouge, Ascension and Iberville parishes want the Pontchartrain Levee District to take the lead in a plan to clear and dredge portions of Bayou Manchac.

Mayor-President Sharon Weston Broome, Ascension Parish President Kenny Matassa and Iberville Parish President Mitch Ourso sent the levee commission president a letter last week asking for help with permitting through the U.S. Army Corps of Engineers and other agencies.

"Your regional scope and expertise makes the Pontchartrain Levee District the ideal candidate to serve as an applicant (for the permits)," the parish leaders wrote in the Sept. 27 letter.

The letter comes after the parish leaders and those for Livingston and St. James parishes met in January for a regional drainage summit to discuss possible responses to the March and August floods of 2016.

Some environmentalists raised concerns previously that dredging and removal of native trees could affect the aquatic health of the state's historic and scenic river, but state Sen. Mack "Bodi" White, R-Baton Rouge, authored legislation earlier this year exempting some dredging restrictions on the bayou, as well as other scenic waterways. 

Officials from the parishes and engineering firms took a tour of the bayou last week to highlight problem areas. Then a few days later the representatives from the Corps of Engineers, levee district, Ascension Parish and others met in Matassa's office in Gonzales about improvements to the bayou.

Matassa said that corps officials told him then that one permit applicant would be needed for the project. It will need three different kinds of permits, including a wetlands permit from the corps, the parish leaders say in the letter.

"At the meeting, I asked the Pontchartrain Levee District if they would go after the permit," Matassa said Monday.

He said that Blaine Sheets, a levee district commissioner at that meeting, then told him that if Matassa got all three parishes to sign off in a letter asking the levee district to get the permit, Sheets would bring it to the full commission. Matassa said East Baton Rouge and Iberville officials later agreed.

Ricky Bosco, president of the levee board, said the district received the request Monday and it would be presented to the full levee Board of Commissioners, as are other requests from parishes in the levee district. 

"We are looking forward to moving this matter forward in an effort to address concerns of the affected residents and businesses of the area," Bosco said.

The district is responsible for the east bank Mississippi River levees between the Jefferson-St. Charles Parish line and Baton Rouge, as well as 10 miles of hurricane protection levee in St. Charles, but also has a hand in other drainage, coastal restoration and flood protection projects and studies, including those laying out previously stalled plans for Manchac.

The parishes were divided over that older plan, coordinated through the levee district, which proposed dredging and new drainage control structures to improve downstream flow but also to control backwater flooding in the bayou.

Bayou Manchac serves as a downstream drainage outlet for East Baton Rouge, Ascension and Iberville parishes, including growing parts of southern East Baton Rouge and Prairieville in northeastern Ascension, but empties into the Amite River and is susceptible to backwater flooding.    

Ourso said the latest concept, as explained to him, would focus on dredging and clearing out natural blockages in the waterway, not on new drainage control structures.  

Ken Dawson, chief administrative officer for Ascension Parish, said as much, saying the parishes are still working on the extent of the proposed dredging project.

In August, Bill Roux, Ascension Parish's public works director, told the East Ascension drainage board that the parish wants to use a portion of the $33 million in federal hazard mitigation money it will receive for the August 2016 flood on the project but is also looking for cost-sharing from Iberville and East Baton Rouge. He estimated the cost then at $5 million. 

Matassa added that the parishes had previously agreed to share in the cost of the work. While Ourso said he agreed with that concept, Fred Raiford, city-parish transportation and drainage director, said the city-parish supports the need for projects with regional benefits but wants to see more modeling data on the extent of the drainage benefit before agreeing to funding. 

"Those are the things that we want to look at, with factual technical data, not political data," Raiford said.

Meanwhile, Iberville has recently begun a $2.4 million project to upgrade an existing floodgate and add two new floodgates that would drain Alligator Bayou and portions of the Spanish Lake area inside Iberville into Bayou Manchac.

After the August 2016 flood, high water runoff from East Baton Rouge over-topped Manchac Road and went into Spanish Lake and Bluff Swamp, flooding homes in Ascension and Iberville parishes but also trapping the water behind the elevated Manchac Road for weeks. Officials in Ascension and Iberville parishes were forced to make temporary road cuts to drain the area.   

Manchac Road has been closed since the flood. Ourso said the road would be repaved and reopened after the floodgate project is finished in summer 2018.

Dredging and similar kinds of improvements on Bayou Manchac, a state historic and scenic river, require approval by the state Department of Wildlife and Fisheries in consultation with the departments of Tourism and Environmental Quality, state Division of Administration and other agencies. State already law allowed "maintenance dredging" and snagging in Bayou Manchac, but White's legislation added "clearing." Wildlife and Fisheries retains the final say.

The exemption, which Gov. John Bel Edwards signed June 12, doesn't take effect until June 30, 2018.

Follow David J. Mitchell on Twitter, @NewsieDave.