Forest Route 157 / Tamarack River

Forest Route 157 / Tamarack River

County: Iron

City/Township: Stambaugh Twp.

Location: Forest Route 157 / Tamarack River

Year Built: 1918

About this Bridge:
Located near the Gogebic County line, this medium-span concrete bridge carries Forest Route 157 (Old US-2) over the Tamarack River on the Ottawa National Forest. The bridge was constructed in 1915-1916 from a MSHD standard design. It is comprised of a pair of 50-foot, concrete girders that rest on concrete full-height abutments with angled wingwalls. The girders support a 18-foot-wide concrete deck in the through position. Using typically modest MSHD detailing, the bridge features recessed rectangular panels on the outside walls of the girders, massive copings on the girders’ tops, and bronze “Trunk Line Bridge” plates (since removed) mounted on the girders’ inside walls. The San Souci Bridge, as it was historically known, has suffered a minor amount of spalling of its copings, but it is unaltered and retains a relatively high degree of structural integrity.

In March 1914 the Marquette Mining Journal reported: “Automobile owners in Ishpeming and Negaunee are taking much interest in the campaign now being conducted in Gogebic county for the completion of the trunk line road between that county and Iron county... The project is one that has been under consideration for months. In addition to the benefit to be derived by automobile owners from the completion of the trunk line road, a large undeveloped agricultural country would be opened up, and the road would also give the settlers in the district traversed an opportunity to get to and from the markets.” Additionally, the road would open a large portion of the Upper Peninsula to tourist traffic. During the 1910s the road was developed through the two counties; it linked Crystal Falls, the Iron County seat, with Iron River and Gogebic County on the west and Mansfield and Dickinson County of the east. The county road commission used state reward funds to improve the route in the late 1910s, grading segments of the roadway and building bridges and drainage structures along its length.

Between Iron River and the county line the road made three river crossings: over Cook’s Run River, The Paint River and the Tamarack River. These were all to be 50-foot concrete girder spans. In 1915 MSHD awarded Barnum and Counihan the contract to build a bridge at the Tamarack River. The builders completed the bridge the following year for $2,826.10. The bridge marked the completion of the last link in the highway. In July 1916 the trunk line route – designated the Cloverland Trail – was dedicated ceremoniously at San Souci. Attended by some 1,500 people in 275 cars, it was reported as “the largest assemblage ever seen in the Upper Peninsula.” In the 1920s the trunk line later developed into US-2, but by 1942 this segment had been abandoned in a highway re-alignment. The road is now a forest route on the Ottawa National Forest, and the San Souci Bridge still carries vehicular traffic, in essentially unaltered condition.

The concrete through girder that MSHD built here was based on a standard design that the agency had developed in the 1913-1914 biennium. During the 1910s and 1920s, the highway department delineated straight girders in five-foot increments between 30 and 50 feet for used in a wide variety of application. “The reinforced concrete through girder is the design generally employed for spans from thirty to fifty feet in both the eighteen and twenty-foot clear roadway from curb to curb,” MSHD stated in its Seventh Biennial Report. “This design lends itself in the majority of cases on account of its very shallow floor system, thereby giving the waterway a maximum clearance under elevation of roadway crossing the bridge.” The three bridges built in 1915-1916 in Iron County were among the first through girders designed using the standard plan; they were exceeded in age by only the Red Cedar Bridge in Ingham County and the Peshekee River Bridge in Marquette County. With the subsequent demolition of Red Cedar Bridge and the other two Iron County structures, the San Souci Bridge is technologically significant as one of the two oldest concrete girder bridges undertaken by MSHD. Built as an integral part of one of the Upper Peninsula’s most important routes – the bridge most closely aligned with the historic Cloverland Trail – it is an important transportation-related resource.