The St. Charles County Highway Department maintains and improves existing public county roads, constructs new roads, and provides snow removal and oversight of the public right-of-way.

The department is comprised of approximately 115 employees in both the field and office, and is comprised of laborers, equipment operators, technicians and engineers.

County Streets/Roads

County roads are any public road located outside the jurisdiction of the various cities in the County and that are not part of the state system. For information on future projects on county roads, contact the Highway Department Office by calling 636-949-7305. 

State Maintained Highways

The state highway system includes any numbered (I-70, Route 94, etc.) or lettered route (Highway K, Highway DD, etc.). The state is also responsible for the traffic signals along these highways and overpasses. You may contact them at 314-275-1500 or 888-ASK-MODOT.

Municipality Maintained Roads

Streets within cities are typically maintained by the city, with the exception of smaller municipalities such as Cottleville, Weldon Spring, St. Paul, etc., who contract with the County to have their streets maintained by the County Highway Department. View the current municipality boundary map (PDF)Cities that conduct their own maintenance are:
  • Augusta
  • Lake Saint Louis
  • O'Fallon
  • St. Charles
  • St. Peters
  • Weldon Spring Heights
  • Wentzville