WATSON — The Army Corps of Engineers and the Kansas City Southern Railroad have reached an agreement in principle on long-term maintenance for a new railroad bridge planned over the future Comite River Diversion Canal, a Corps project manager said Wednesday.

The agreement, which the Corps expects to sign at the end of the month, clears a potential delay to the diversion channel designed to reduce flood risk in the lower Amite River Basin and is expected to kick construction into gear for one aspect of the 12-mile long canal early next year, officials said.

The diversion will draw water from the Comite River and, through gravity flow, send it into the Mississippi River and away from the Amite River, which the Comite joins downstream.

Congress agreed to spend $343 million last year to help build the channel after the August 2016 flood highlighted the stalled canal's flood reduction potential.

The influx of federal cash provided the last batch of funding to finish the stalled project first proposed after the 1983 flood. Some property owners in Ascension, East Baton Rouge and Livingston parishes have been paying property taxes for nearly two decades to help finance project.

Corps of Engineers and other officials broke ground on the work in April and have been trying to prepare the various segments for construction to meet an aggressive timeline and have the work finished by mid-2021.

But Corps officials revealed in early August that they and the railroad officials couldn't reach a deal on KCS's future track maintenance and operations costs once the bridge was built.

Latest delay on Comite River Diversion Canal carries at least $5 million pricetag, officials say

U.S. Rep. Garret Graves, R-Baton Rouge, an ardent backer of the diversion channel who helped woo the construction dollars from Congress, threatened last month to encourage the Amite River Basin Commission to use its expropriation power to take the railroad's property to get access for the project if negotiations didn't soon come to a resolution.

But Bobby Duplantier, a Corps senior project manager, said Wednesday that his agency and the railroad agreed on the value of the railroad's extra costs over the bridge's 50-year life span. He said expropriation won't be necessary.

"We've come to an amicable agreement," Duplantier said in response to a question during a commission meeting at the Livingston Parish Library branch in Watson. 

The Corps plans to build a 300-foot-wide channel under the tracks and the next-door U.S. 61. The highway and KCS track in that area currently cross on solid ground but will need bridges to cross the future canal. 

C. Doniele Carlson, a spokeswoman for KCS, confirmed the two sides had reached an agreement "on how to address issues concerning the proposed new rail bridge needed for the project."

"The Corps is moving forward with what it needs to do under the terms that have been agreed to by both parties," she wrote in an email Wednesday.

Duplantier said the negotiations with KCS have not delayed the diversion canal's overall timeline and allowed utility work to be completed and get out of the way of the future bridge construction.

Duplantier said that with the agreement in place, the Corps plans to award a construction contract for the railroad bridge and two bridges for U.S. 61 in the fourth quarter of this year, with a construction start in the first quarter of 2020.

He added that six other phases of the project, including contracts for significant sections of channel digging, are expected to be ready for construction bidding and award in the fourth quarter of the year.

Corps officials have estimated just the construction cost of the KCS and U.S. 61 bridges and related work such as digging a small portion of the diversion channel — but not including the new maintenance deal — will be between $15 million and $30 million. 

Before the agreement, the Corps had already planned to pay the full cost to build the new rail and U.S. 61 bridges and also cover the extra long-term operation and maintenance costs. The Corps is also planning to pay to build road and rail bypasses while the canal segment and bridges are under construction.

Duplantier said the Corps recognizes the railroad will face extra costs in the long term due to the bridge and he calls its agreement with the railroad a "reimbursement."

"Once we come through and we build this bridge, they are going to be responsible for that bridge into perpetuity," Duplantier said.

Negotiations over the value of the railroad's extra costs included the maintenance of large support piles that will hold up the bridge, he said.

He said he could not yet disclose the value of the maintenance until the deal is final, but he said it is within the project's total budget.

The future diversion canal will start at the Comite between Zachary and Baker and head west to the Lilly Bayou Control Structure, which takes water to a bayou that leads to Mississippi. 

The Corps finished the $30 million control structure in early 2011, but the project to dig the actual channel ground to slow crawl in the years afterward as the project sponsors were stymied by a lack of funding. 

The railroad and U.S. 61 bridges are among 13 features designed to reroute roads, railroads and other infrastructure in the way of a canal that will cut cross-country through northwestern East Baton Rouge Parish. 

The Corps still has to negotiate a similar bridge maintenance agreement with another railroad.

As downstream parishes watch, Corps reanalyzes expected impact of Baton Rouge drainage plan

Email David J. Mitchell at dmitchell@theadvocate.com

Follow David J. Mitchell on Twitter, @NewsieDave.