The Missouri Highways and Transportation Commission awarded a construction contract to seal coat two state highways in Callaway County.

More than 18 miles of Route D from I-70 in Williamsburg to Route 94 will be seal coated to extend the life of the roadway pavement.

Almost six miles of Route K will also be seal coated from Route D to the Montgomery County line.

The work includes seal coating the roadway surface to prevent water from entering cracks in the pavement and deteriorating the road.

The process consists of placing small aggregate on top of the sealant as it dries.

Crews return after the treatment to sweep the remaining loose material from the road surface.

"This process is an important step in helping to maintain a roadway," said MoDOT Transportation Project Manager Trent Brooks. "By preventing water from entering the driving surface, we are able to extend the life of highway pavement by several years."

The contract also includes seal coating almost 33 miles of Route 94 from Route 19 near Hermann to Route T near Augusta.

Chester Bross Construction C.O./C.B. Equipment, Inc. of Hannibal, Mo. was awarded the contract after submitting the lowest bid of $1,105,282.56.

Work can take place between May and September 2012.

Once work starts on a route, the contractor has 30 days to finish the work on that roadway.

Motorists should expect lanes closures and to be flagged through the work area.

"We appreciate motorists' patience and cooperation while we work to maintain these roadways" said Brooks. "We encourage the public to view our Traveler Information Map at www.modot.org to learn the location of work zones across the state.