Ocqueoc Falls Hwy. / Ocqueoc River
County: Presque Isle
City/Township: Ocqueoc Twp.
Location: Ocqueoc Falls Hwy. / Ocqueoc River
Year Built: 1920
About this Bridge:
Located some four miles north of Millersburg, this graceful concrete arch bridge spans the Ocqueoc River on the Ocqueoc Falls Highway. The crossing is situated at a dogleg on what used to be M-68, immediately downstream from a mill site. This highway has more recently been re-aligned to eliminate the dogleg; the bridge now carries a county road.
The structure is configured as a 50-foot, filled spandrel arch with an elliptical profile. The arch springs from massive concrete abutments, which feature battered backwalls and angled wingwalls. The tapered arch ring of the Ocqueoc River Bridge is corbeled from the spandrel on each side. This, and the MSHD standard paneled concrete guardrails, provides the bridge's architectural expression. Bronze "Trunk Line Bridge" plates are mounted to the insides of the guardrail walls. In unaltered though deteriorated condition, the Ocqueoc River Bridge has retained a high degree of physical integrity.
In 1913 the Michigan State Legislature passed the State Trunk Line Act, which authorized the designation of a trunk-line network totaling nearly 3000 miles. The act stipulated that the state highway department would design, build and maintain trunk line bridges spanning 30 feet or more, if the county or local government improved three miles of adjacent road.
Soon after its passage, a mainline route across Presque Isle County was designated. The route extended from the south county line, northwest to Rogers City, the county seat, and from there ran due west to the Ocqueoc river near the Ocqueoc Falls, before dropping south to Millersburg. The road was largely complete by 1915.
It was not until 1919, however, that the state highway department moved to bridge the Ocqueoc at the Ocqueoc Falls dogleg. That fall the highway department solicited competitive proposals for the bridge's construction but did not award a contract. MSHD later re-bid the project, hiring the Rogers City contractor John Decker to build the bridge. In 1920 Decker completed the Ocqueoc River Bridge for $8,849. The trunk line was later incoporated into US-23 and M-68; in 1954 the highway was re-aligned over a new bridge, and the 1920 span now carries local traffic on a county road.
Upon the bridge's completion, the state highway department deemed it "notable for the excellence of the workmanship." The bridge that the highway department engineers delineated for the Ocqueoc River crossing was one that they had only just begun using. MSHD began designing concrete arch bridges as early as 1908, but, unlike its practice on the other structural types, the agency did not develop a standard concrete arch design. The bearing and superstructural conditions were too site-specific, MSHD stated, making standardization of concrete arches impractical. Instead, the highway department used special-design concrete arches up to 80 feet in length "wherever it is possible to secure sufficiently hard foundations, and also where there is clearance enough for water to flow freely without the arch choking the stream too much," according to its Seventh Biennial report.
In 1914 MSHD built its first state arch for Trunk Line Bridge No. 3 – a 50-foot span over Plaster Creek in Kent County. As the trunk line system developed in the 1910s, MSHD built several more arches. By 1920 the agency had constructed some 27 trunk line arches, ranging in span from 31 to 100 feet. The Ocqueoc River Bridge in Presque Isle County is distinguished as one of the few of these that continues to carry vehicular traffic in unaltered condition.