M-115 starts in downtown Clare at a four-way intersection with the two
business loops, Bus. US 127 and Bus. US 10, in town. From this junction, M-115 runs west following the former routing of US 10 along Ludington Drive to Farwell. In the middle of town, M-115 turns northwesterly to meet the end of the US 10 freeway near Surrey Lake. The highway continues northwest through forest lands and lake country. The trunkline passes into northern
Osceola County near its crossing of the
Muskegon River. There are intersections with both
M-66 and
M-61 south of
Marion near rural farms. The roadway subsequently crosses into southern
Wexford County. Near Stone Lake south of Cadillac, M-115 meets
US 131 and
M-55. M-55 leaves the US 131 freeway and joins M-115, and the two
run concurrently along the western end of
Lake Cadillac. They separate near
Lake Mitchell, and M-115 turns northwesterly between the two lakes passing
Mitchell State Park and the eastern shore of the latter lake. The highway continues through woodlands, passing several small lakes in the area as it approaches the community of Mesick. There it turns due west and joins
M-37 through town. After M-37 separates to the south, M-115 crosses the
Manistee River and continues its northwestern course. The highway crosses the northeastern corner of
Manistee County and runs through the community of
Copemish on the way to
Benzonia. The landscape here turns more agricultural as the highway skirts southwest of
Thompsonville crossing the
Betsie River. The
Michigan Department of Transportation (MDOT) maintains M-115 like all other trunkline highways in the state under its jurisdiction. As a part of these responsibilities, the department tracks traffic volumes along its roadways until a metric called
average annual daily traffic (AADT). This number is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2009, MDOT determined that the highest traffic levels along M-115 were the 12,079 vehicles daily along the section of highway near lakes Mitchell and Cadillac. The lowest AADT was the 2,236 vehicles near Copemish. The trunkline between the US 10 and M-37 junctions has been listed on the
National Highway System. a network of roads important to the country's defense, economy and mobility. ==History==