Interstate 20 in Vicksburg will be elevated in parts, widened to six lanes in parts and its interchanges rebuilt, according to plans to be shown to the public Thursday.

The Mississippi Department of Transportation plans to widen to six lanes six miles of interstate between the Washington Street/Warrenton Road exit and the U.S. 61 North/Mississippi 27 exit, three in each direction. The plan also calls for overpasses at Halls Ferry Road, Clay Street and Wisconsin Avenue to be redesigned over an undetermined period of years. Traffic on the frontage roads would be turned one-way while lanes are widened, exits are reconfigured and detours are built.

MDOT says it will lay out two alternatives during a free-flowing public hearing set for 4 p.m. at the convention center.

A spokesman said the department has a plan to improve Indiana Avenue from its mishmash of unprotected turns and ramps.

“This is part of the closing of the environmental study,” said Kevin Magee, MDOT Central District engineer, referring to a review by Jackson-based Neel-Schaffer Inc., which was started in 2006. “If (people) came before, they still need to see what we have now.”

After the hearing, the study heads to the Federal Highway Administration and the state will move on to buying rights of way, moving utilities and, ultimately, construction.

The total cost is expected to be $100 million, according to MDOT’s current four-year plan for highway projects, which runs through 2013. About $12.3 million was spent on all phases thus far, leaving the project in need of $88 million in federal highway cash.

“A lot of people commented on Indiana Avenue,” Central District Commissioner Dick Hall said of the last public hearing on the project, in November 2009. “It’ll all be done at some later date.”

In a draft environmental impact report, each frontage road’s intersection with Indiana would be rebuilt farther north or south if frontage roads return to two-way traffic. Interchange ramps would connect directly to the frontage roads if traffic is kept in one direction, a plan that has North Frontage traffic traveling west and South Frontage going east.

Copies of the report are available in Vicksburg at the Warren County Board of Supervisors office on Jackson Street, Vicksburg City Hall, Vicksburg Warren County Chamber of Commerce on Mission 66, Warren County-Vicksburg Public Library and Vicksburg National Military Park.

Features favored during the last presentation included a flyover ramp from Halls Ferry Road to replace a left exit onto U.S. 61 South and expanded eastbound lanes to ease congestion at the left exit for U.S. 61 North.

South Frontage Road would be elevated above rail tracks near the Outlets at Vicksburg, with new portions of the roadway to be maintained by the city. Access to eastbound lanes from Clay Street and U.S. 80 would be improved via a wider interchange and an extra lane.

As with the I-20 makeover, building the South Frontage Road extension has no firm start date. In October, Hall gave the project 18 months to start. The I-20 work is designed assuming a new, longer South Frontage is complete. That’s not looking likely, Magee said. MDOT has purchased multiple pieces of land along Old Highway 27 and Porters Chapel Road where the elevation is planned.

Businesses along I-20 have been up in arms for years about what’s in store for the frontage roads after the interstate is widened. A video presentation by MDOT at the last meeting showed one plan with one-way frontage roads, similar to Interstate 55 through Jackson, while a second plan returns them to two-way traffic as they’ve been since the interstate was completed in Vicksburg around 1973. In the preliminary report, that remains the biggest difference between two major alternatives for the interstate system in Vicksburg.

“I don’t understand why we need one-way frontage roads,” said Alan Atwood, one of the owners of Atwood Chevrolet, one of three car dealerships bunched within a mile of each other on North Frontage Road. “I look out my window and I never see traffic backed up. Our frontage roads aren’t backed up. We’re not Jackson.”

Using I-55’s layout in Jackson as a model for I-20 in Vicksburg might not be an apples-to-apples comparison, some contend.

Pat Cashman, publisher of The Vicksburg Post, said a support system of roads eases traffic near the capital city’s one-way frontage roads near I-55. No such nexus exists in Vicksburg, he said.

“It would kill businesses on both frontage roads,” said Cashman, whose company owns Post Plaza on North Frontage Road near the intersection with Halls Ferry Road. “Plus, in Jackson, you have networks of roads behind each frontage road you can use. It’s just a horrendous expense for a problem that’s not there.”

Cowboy Maloney’s Electric City store in Vicksburg is on South Frontage Road, also near Halls Ferry. On maps shown to the public in 2009, an underpass was drawn in front of the strip mall that houses the electronics and appliance outlet, Big Lots, Tractor Supply and Asian Kitchen.

Cowboy Maloney’s store at I-55 and Briarwood Drive in Jackson is close to the interchange, making it easily accessible for customers, said co-owner Johnny Maloney. One-way traffic on South Frontage Road in Vicksburg without similarly conven-ient crossovers make it a bad idea for a business that is “booming” in a slow economy because of refrigerator, freezer and flat-screen TV sales, he said.

“One-way traffic would not be good for retail business there,” Maloney said. “We got a good gig going right now. We don’t want to see it end.”

Daily traffic counts along the interstate in Vicksburg for 2011 totaled about 47,000 vehicles at the highway’s busiest point, between Indiana Avenue and Clay Street. Over the past decade, it’s averaged about 46,200 vehicles per day, according to MDOT.

Others say the work and its costs would be worth it to expand the interstate and eliminate outdated intersections of I-20 and U.S. 61 north and south and to lengthen short on-ramps at Clay Street.

“Change and progress is painful,” said J.E. “Brother” Blackburn, whose car dealerships moved to North Frontage Road six years ago. “But, long-term, it’s worth it. We’re long overdue for something like this,” he said.

Randy Wright, owner of Goldie’s Trail Bar-B-Q on South Frontage, attended the 2009 meeting and asked when the massive undertaking would arrive at the restaurant’s doorstep. He was told “no set time.”

“I might not be here to see it,” he said. “But, I’m an old country boy. If it ain’t broke, don’t fix it.”

Ideally, frontage road traffic should flow in both directions, Wright said.

“I love the idea of having six lanes,” he said. “I wouldn’t change a thing from their plans — other than we keep the frontage roads going two ways.”