M-33 (Michigan highway)

M-33 starts at exit 202 on I-75 near Alger.[3] From there it crosses a branch of the Lake State Railway[4] and Old 76 Road before turning north. The highway runs north parallel to the Rifle River across the Arenac–Ogemaw County line. It meets the eastern terminus of F-18 and continues through woodland to an intersection with M-55 east of West Branch. North of the junction, the environment transitions to farm land that borders the edge of the Au Sable State Forest to the Rose City area.[3][5] North of Rose City, M-33 crosses into the Huron National Forest as the highway continues due north into Oscoda County, passing Mack Lake campground.[6]

M-33 follows Morenci Avenue into the center of Mio where the highway joins M-72 south of Mio Pond, and they run concurrently together across the Mio Pond section of the Au Sable River out of town. On the north side of the river, F-32 merges in from the east and the three roadway designations run concurrently north. The highway continues to a sweeping 90° turn east near Smith Lake. F-32 separates to turn west and M-33/M-72 turns eastward. The trunkline continues to Fairview where M-33 turns north, leaving the M-72 concurrency to continue northward. M-33 crosses into the Mackinaw State Forest and passes through Comins. North of that unincorporated community, the highway curves northeast, east and back north to cross into Montmorency County. Before reaching M-32, M-33 crosses the Thunder Bay River. After the river, M-33 turns westward along M-32 to the community of Atlanta. The highway passes near the Atlanta Municipal Airport as it enters the community. In the middle of town, M-33 turns back north. The highway provides access to the Clear Lake State Park in northern Montmorency County before crossing into Presque Isle County.[3][5]

M-33 parallels the Cheboygan – Presque Isle county line as it runs northward along the Black River to Onaway. Once in town, M-33 turns west with M-68 toward Cheboygan County. The highway passes through Tower, and a junction with F-05, before it continues west to the Afton area. There M-33 turns north one last time, running along the east shore of Mullett Lake past Aloha and M-212;[3][5] M-212 is the shortest highway in Michigan that provides access to Aloha State Park.[1] North of Aloha, M-33 crosses the Cheboygan River and meets M-27, the location of its northern terminus south of Cheboygan.[3][5]

The Michigan Department of Transportation (MDOT) maintains M-33 like all other state trunkline highways in the state. As a part of these maintenance responsibilities, the department tracks traffic volumes using a metric called average annual daily traffic (AADT). This figure is a calculation of the traffic along a roadway segment for any average day of the year. In MDOT's surveys in 2009, they found that the peak AADT along M-33 was the 6,928 vehicles a day along a section of the M-72 concurrency. The lowest traffic counts were measured immediately south of the Onaway city limits at 956 vehicles daily.[7] The only section of M-33 that has been listed on the National Highway System (NHS) is the segment concurrent with M-32 in Montmorency County.[8] The NHS is a network of roads important to the country's defense, economy and mobility.[9]

M-33 was first designated by July 1, 1919. It ran along the current routing from Mio north to M-32 east of Atlanta. The highway also ran south of Mio to M-76 east of Roscommon using segments of what are now M-72 and M-144.[2] By 1927, the southern section from Fairview to Roscommon was redesignated as a part of M-72. M-33 was shifted to run south of Mio to Rose City instead, creating the M-33/M-72 concurrency in the process.[10] An extension was added by the end of the decade southward to M-55 at Campbell, a former community east of Selkirk in Ogemaw County.[11] An earthen highway extension of M-33 north of Atlanta to US 23 at Onaway was opened in 1934.[12] A few years later in 1938, M-55 was realigned to follow a more direct path east of West Branch. At the same time, M-33 was extended south by a few miles to the new roadway south of Campbell and Selkirk.[13][14] A lengthy northern extension was added to M-33 in 1940 when US 23 was moved to a route along the Lake Huron shoreline between Rogers City and Cheboygan. The former route of US 23 between the Afton area and Rogers City was redesignated as a discontinuous section of M-68, and M-33 was extended westward from Onaway along that highway to Afton and north to US 27 (now M-27) near Cheboygan, creating the M-33/M-68 concurrency in southern Cheboygan and Presque Isle counties.[15][16] By 1945, M-33 was extended southward again, this time to terminate at M-76 in Alger.[17]

The Michigan State Highway Department rerouted M-33/M-72 near Fairview in late 1951 or early 1952, turning the former route back to local control.[18][19] The last section of M-33 was paved in southern Cheboygan County in the late 1950s.[20][21] In 1968, the southern end was extended slightly to end at the new M-76 freeway that opened between Alger and Standish;[22][23] that freeway was redesignated as part of I-75 in 1973.[24][25] A minor realignment of M-32/M-33 east of Atlanta smoothed out some curves in the road in 1996.[26][27]

•  Michigan Highways portal

• M-33 at Michigan Highways