While continuing to take public comments, Missouri Department of Transportation officials are offering some specifics about road and other improvements Missourians would see if they approve a transportation sales tax in August.

“We want people to come and engage with our staff, ask any questions they might have,” Melissa Black, a MoDOT customer relations manager, said at an open house in Blue Springs on Wednesday.

Another open house, one of dozens across the state, is set for 4 p.m. to 7 p.m. today at the Truman Memorial Building, 416 W. Maple Ave., just west of the Square in Independence.

The 10-year, three-fourth-cent sales tax goes on the Aug. 5 ballot and would raise an estimated $5.4 billion. If it passes, the state gas tax would be frozen for 10 years, and there would be no toll roads.

MoDOT has taken suggestions from regional groups – such as the Mid-America Regional Council for the Kansas City area – and developed a tentative project list. Adding information from the open houses, MoDOT is finalize its list in early July.

The centerpiece project is rebuilding and widening Interstate 70 to six lanes statewide. Specifically, that’s everything from Missouri 7 in Blue Springs east to Wentzville; the rest already is at six lanes.

“That’s a project that’s been neglected for a long time,” Black said.

The $1.5 billion project would take $500 million from the sales tax and the rest from available bond funds. It would include a new, six-lane bridge over the Missouri River at Rocheport, west of Columbia. It would take about five years.

MoDOT also would replace five bridges over I-70 in and near Independence to create room for “auxiliary lanes,” that is, a place to pull off onto the shoulder. Those bridges are on Pittman Road, Blue Ridge Boulevard, Crysler Avenue, the Union Pacific Railroad line and Phelps Road. The Mid-America Regional Council puts that cost at $47 million.

Statewide, MoDOT is looking at dozens of projects. All can be seen – and comments can be posted – at www.modot.org/MovingForward. In the eight-county area of west-central Missouri, close to 40 projects are on the list, including:

• Replacing the bridges that carry Interstate 435 over I-70 near the stadiums. That area got a major upgrade a few years ago with federal money meant to stimulate the economy after the downturn of 2008-09. I-70 was widened to six lanes, and access to and from U.S. 40 was improved, among other things.

But the I-435 bridges – a total of four, counting exits – are old and need to replaced, MoDOT says. With the sales tax, that would happen, and left-hand exits would be eliminated. Also, I-435 would flow through that intersection with six lanes, instead of the current four in places. MARC puts that cost at $40 million.

• Replacing the Broadway Bridge in Kansas City – $150 million.

• Acquiring the old Rock Island Line rail corridor from Pleasant Hill north to an area just west of the stadiums. Jackson County, hoping to start commuter rail some day, has worked out a deal to buy that from the Union Pacific. MoDOT would work with the county.

The Katy Trail, popular with hikers and bicyclists, is being extended north from Windsor, Mo., and with that old rail line in hand, the state would be able to extend the trail to the stadiums area, regardless of what happens with commuter rail. Officials have long said both uses would easily fit on the old rail line.

• Improvements to the Lee’s Summit Airport.

• Widening U.S. 50 east of Sedalia. That means a four-lane drive from Kansas City to Jefferson City.

The Missouri General Assembly voted to put the issue on the ballot, but Gov. Jay Nixon, who has come out against the tax, got to decide whether it went to the voters in August or November. He chose August, and that has shortened MoDOT’s timeline to finalize its project list so voters know in detail what they’re voting on.

“We did significantly have to speed up the process, absolutely,” Black said.