With cargo ships getting larger and the Panama Canal getting wider, the U.S. Army Corps of Engineers is once again weighing the costs and benefits of a potential $300 million effort to deepen the lower Mississippi River by as much as 5 feet.

The project — which would cover the stretch from Baton Rouge to the Gulf of Mexico — is being considered largely in light of the multibillion-dollar work underway at the canal, which is slated to wrap up next year.

When the Panama project is finished, the canal will be able to accommodate ships with drafts as deep as 50 feet below the water’s surface. That is 5 feet deeper than what’s available on the lower Mississippi.

For years, local maritime officials have argued that the extra 5 feet of depth are overdue for the sinuous, 175-mile shipping waterway. In fact, Congress authorized the river to be dredged to 55 feet in the 1980s, 10 feet deeper than it is now. Each additional foot means more cargo that ships can carry, and that means more money.

And as the Panama Canal expansion moves closer to reality, leaders at the country’s major ports have scrambled to do what they can to accommodate the deeper-draft vessels that are expected to follow.

A 2012 study by the American Society of Civil Engineers found that the $14 billion in upgrades then planned for U.S. ports and waterways represented only about half of what was needed to fully reap the benefits of the canal expansion.

As the Corps now considers deepening the lower Mississippi, it will study the environmental impacts of the project, as well as its price tag — which may hit $300 million — in order to determine whether its cost is justified by the expected benefits.

The agency has three public meetings scheduled this week to discuss the study, including one at 9 a.m. Thursday at its New Orleans District offices at 7400 Leake Ave.

The Corps is responsible for maintaining the river channel, including dredging it, a costly exercise that prevents silting that would hinder ship traffic. For the 2015 fiscal year, the agency has $95.3 million budgeted to operate and maintain the waterway, according to spokesman Ricky Boyett. But the deeper channel would drive those costs up even higher.

Ultimately, the Corps’ study will try to determine the amount of additional depth — up to a maximum of 5 feet — that will bring the biggest return on investment.

Public comment for the study is slated to stretch through next month. The Corps will then begin evaluating the project, with an eye toward selecting a tentative depth by August 2016. Another public-comment period will follow, with a final report due in late 2017.

Landing the extra 5 feet in the channel has been a top priority for Gary LaGrange, president and CEO of the Port of New Orleans. In years past, the goal seemed out of reach because of the high yearly maintenance costs, he said. But that hurdle was lifted last year when Congress passed a law that puts the federal government in charge of paying for channel maintenance up to 50 feet, 5 feet more than in the past.

LaGrange said the extra depth will more than pay for itself in the form of new tax revenue from billions of dollars in new spending. All of that, he believes, will create upward of 17,000 new jobs across the country.

LaGrange points to a 2013 report — compiled by local economist Tim Ryan and paid for by the Big River Coalition, an advocacy group — that predicts the extra 5 feet in the channel would mean an additional 24 million tons of cargo would flow through southeast Louisiana ports over an eight-year span beginning in 2017. Over the first 20 years after the deepening, new spending generated by the project could hit $5 billion in Louisiana alone, according to the report.

Big-bulk shippers of products like petroleum and grain would stand to benefit the most, though upticks in container traffic also would be expected. The study anticipates a deeper channel would boost imports of crude oil, iron and gasoline, and exports of corn, soybeans and coal.

Container traffic — the New Orleans port’s bread and butter — would initially grow by as much as 7 percent locally, LaGrange said, and Gulf Coast ports could expect it to pick up by as much as 15 percent over the next decade.

Though the Corps’ final figures may not be as rosy as Ryan’s, LaGrange said he’s confident the agency will find that the project makes financial sense.

“Even if they decreased the numbers by half, it’s still phenomenal,” he said.

The study is being paid for by the Corps and the state Department of Transportation and Development.

Follow Richard Thompson on Twitter, @rthompsonMSY.