Chip Seals

Chip Sealing Adds Life to Missouri Roads, Saves Taxpayer Dollars

A chip seal operation entails spraying a heated film of asphalt liquid on the road, followed by placing fine rocks or chips on top. The chips are then compacted to make them adhere to the roadway. Finally, the excess loose chips are swept from the surface, leaving an improved roadway that will hold up longer than it would have without the treatment.

Chip seals are about one-third the cost of a conventional asphalt overlay, averaging $15,000 per mile as compared to an estimated $55,000 per mile for an asphalt overlay. Chip seals keep damaging water from penetrating paved surfaces and extend the life of the pavement for an additional five to seven years. Chip sealing also seals cracks and improves roadway traction. 

A surface may be chip sealed several times, providing the road remains structurally sound. The chip seal process is typically used on roads carrying lower traffic volumes which make up more than half of MoDOT’s roadway network.

Motorist Safety

Motorists need to observe the speed limit of 35 mph on roads where chip sealing is in progress. 

Motorists should also be aware that flaggers and pilot vehicles are frequently present at chip seal operations, and vehicles may be required to come to a complete stop. Traffic delays are possible, so travelers should consider alternate routes, if available.

Road condition information is available 24/7 on MoDOT’s Traveler Information Map located at modot.org or through MoDOT’s smartphone app which can be downloaded free for iPhone and Android phones.