Following the closing of the iconic Cottage Grove Swinging Bridge in 2016, community members and city employees worked to secure funding and grants and to make a plan for its safe replacement. The replacement bridge should be complete in late fall of 2019.
The Swinging Bridge, which has been a prominent city landmark since the 1920s, was closed nearly three years ago after being deemed unsafe by the City Engineer Ron Bradsby.
“The Swinging Bridge is an important piece of history for our community. Rebuilding it has been a great partnership between grass roots efforts, dedicated engineers, contractors and the city. We are all excited to add the bridge back to our walkable, beautiful neighborhoods,” said Ryan Sisson, civil engineer for the City of Cottage Grove. “We also want to extend the city’s sincere appreciation to the Oregon Parks and Recreation for issuing a grant in the amount of $200,000 that will be applied to the guaranteed maximum price of $804,000 for the bridge.”
From the beginning, the new swinging bridge has been a true effort in collaboration between the city, Ausland Group for design and Hamilton Construction Co. Together, the three entities found a way to make the replacement bridge safe, economically feasible and emblematic of the historic bridge. The new bridge was designed by engineers at Ausland Group, an engineering/architecture and construction firm in Eugene, and is being built by Hamilton Construction Co.
“It is a privilege to partner with the city and local firms to create a lasting icon for the community,” said Karl Stelljes, Hamilton Construction’s project manager. “Our project team includes many local suppliers and fabricators which made it truly a local collaborative effort to be proud of.”
The new suspension design captures the historic swinging and aesthetic character of the previous bridge, as well as meets modern codes for safe pedestrian bridges. Common materials were specified and some elements, like the concrete piers and angle-iron floor beams used to hold the decking, were reused to keep the project economical. The new bridge will retain some of its characteristic “swinging” movement and use a non-slip synthetic decking material, called pultruded fiberglass, commonly used for marine docks.
“This really is a feel-good community project and it is great to be associated with it,” said Greg Ausland, the design project manager for the Swinging Bridge. “Ausland’s bridge designer Tony LaMorticella and I have worked on a lot of bridges together throughout the state and this one is special because of how unique it is and the level of community support it has.”
The design retains many of the original bridge characteristics, but the new bridge will be much stronger. The new weathering-steel towers, which replace existing rotting wood towers, will form a patina and not need to be painted. At one-and-a-quarter inches thick, the high-strength steel bridge strand cables will only be a quarter inch thicker than the existing strands yet will be nearly three times stronger at a 96-ton breaking strength. The stainless-steel bridge rail will also be about a foot higher to adhere to building code for bicycle traffic.
“It is an integral part of the Cottage Grove community because generations of local families have used it to get to school, visit neighbors and relatives, had their first date (and sometimes kiss) on that bridge, etc.” said Dana Merryday, who heads up the Friends of Cottage Grove Swinging Bridge community group. “Ask anyone who grew up in Cottage Grove and immediately they will start telling you stories about their connection and experiences on the bridge.”
“A huge stack of letters written by supporters at our first benefit helped secure a state Parks & Recreation Grant that helped make the project a reality. We are very happy both with the Ausland design and the Hamilton installation. It’s a very good fit for the job and for our community,” Merryday said.
The bridge has been replaced several times including a truss bridge that was swept away in a flood during the 1960s. The most recent bridge was rebuilt in the early 1970s.
Demolition began June 24 and construction of the replacement bridge is slated to continue through late fall 2019.