Route 109 is a state highway in
St. Louis County, Missouri and
Jefferson County, Missouri
Jefferson County is located in the eastern portion of the state of Missouri. It is a part of the St. Louis Metropolitan Area. As of the 2020 census, the population was 226,739, making it the sixth-most populous county in Missouri. Its county ...
. Its northern terminus is at Wild Horse Creek Road in
Chesterfield; its southern terminus is at Routes W and FF in Jefferson County. The road continues north, curves around
Spirit of St. Louis Airport
Spirit of St. Louis Airport is a public airport located 17 miles (27 km) west of the central business district of St. Louis, in St. Louis County, Missouri, in the city of Chesterfield, United States. It is owned by St. Louis County and ...
and connects with Chesterfield Airport Road, providing a "backway" to the
Chesterfield area.
History
Route description
The
Missouri Department of Transportation commissioned Route 109 sometime between 1937 and 1938 as a state-maintained access road to
Babler Memorial State Park from Route C in St. Louis County. What is now the current alignment of Route 109 was then designated as Route C and ran north from
Route 100 to its terminus at Route CC (Wild Horse Creek Road) in Chesterfield. The portion of Route 109 running south from Route 100 was signed as Route B and terminated at Interstate 44.
Sometime between 1956 and 1957, the Route 109 designation was extended to cover Route C south of Babler State Park and Route B between Route 100 and Interstate 44. A bridge was built over the
Meramec River
The Meramec River (), sometimes spelled Maramec River, is one of the longest free-flowing waterways in the U.S. state of Missouri, draining Blanc, Caldwell, and Hawk. "Location" while wandering Blanc, Caldwell, and Hawk. "Executive Summary" fr ...
linking Route W from
Jefferson County to Route 109's southern terminus at Interstate 44 in 1974, but this bridge was later designated to carry Route 109 into Jefferson County, moving its southern terminus to the intersection of Routes W and FF just south of the Meramec River.
In 1999, Route C was fully decommissioned in St. Louis County. Route 109 assumed Route C's previous alignment and the old section of Route 109 that ran to Babler State Park was renamed Route BA (the only such route designation in Missouri).
This change renamed the last remaining section of Route 109's original routing.
Major intersections
References
109
Transportation in Jefferson County, Missouri
Transportation in St. Louis County, Missouri
{{Missouri-road-stub