Traverse

Traverse. . , At least three bridges have been built to allow passage over the Big Sioux River in this location, ranging from a single span steel truss structure to a three-span reinforced concrete arch bridge., By the numbers , Total Bridge Length: 241.2 Feet , Length of Largest Span: 85.3 Feet , Deck Width: 52.2 Feet , Average Daily Traffic (2019): 6,500, 8th St Bridge , The Eighth Street bridge was built in 1912 and consists of a three-span concrete, closed-spandrel arch bridge over the Big Sioux River. The bridge is unique in that the structure is concrete, but the interior is earthen filled (granular fill). The bridge was constructed by N.M Stark and Company, from Des Moines, Iowa, a company that specialized in reinforced concrete bridges., The bridge was listed on the National Register of Historic Places in 1993 and was recognized for its notable bridge piers, neoclassically detailed balustrades, and elegant iron light poles., image: , Eighth Street Bridge, ca 1916 , Courtesy GreetingsFromSiouxFalls.com, Rehabilitation , The Eighth Street bridge is over a hundred years old but has had limited upgrades over the years. In the 1970's the bridge underwent rehabilitation and restoration work, including streetscape improvements. By 2015, city leaders recognized the need for bridge repairs or replacement. Engineers were hired to evaluate the structure, and they developed options to either repair or replace the bridge., The decision was made to repair the bridge at a cost of $8 million, and the project underwent years of planning and public input before being developed into a set of construction documents. Bridge construction was completed in the fall of 2020, and the associated greenway improvements were done by the spring of 2021., The 2020 Project , To rehabilitate the bridge, the construction team first began building a temporary work platform beneath the bridge so that crews could remove and repair damaged concrete beneath the arches. These removals were done by hand or through hydrodemolition, a process that uses high pressure water to remove the concrete. The contractor then repaired the surface with shotcrete, which is a spray on concrete finish. Hand tools were used to finish the final surface to match the historic texture., At the same time, the road and walk surfacing was removed from the top of the bridge, and the granular fill was excavated. Special care was taken to remove the fill evenly from both sides of the bridge as to not disturb the structural stability of the bridge. Crews repaired damage on the tops of the arches on the inside of the bridge, and waterproofing membrane and drain tile was added. New fill was brought in, utilities upgraded, and surfacing for the road and walks reinstalled. Light improvements were incorporated into the project as well, including more efficient LED fixtures and color changing arch lighting., Additional improvements associated with the project included greenway trail improvements of widened bike trail, river retaining wall, and this interpretive exhibit wall., images: , Utilities located in temporary overhead ducts , Bridge with road surface and fill removed , Waterproofing membrane installed over tops of arches, images: , Concrete removals on south side of bridge , Concrete removals beneath bridge arch , Concrete removals on north side of bridge, plaques: , Restoration of the Eighth Street Bridge , City of Sioux Falls , Rick W. Knobe, mayor , David A. Witte, commissioner , Vernon G. Winegarden, commissioner , 1977, Board of County Commissioners , Minnehaha County, So. Dak. , Thos. McKinnon, chairman. , A. Atcheson C. Harvey , A.J. Johnson J.E. Johnson , J.L. Wagner, County Engineer. , 1912, Designed and Built by N.M. Stark and Co., , Des Moines, Iowa. , 1912. , Backgrounds: , (left) Original Bridge Sections from Marsh Bridge Company Construction Drawings, 1908 , Selfie Wall: Eighth Street Concrete Bridge and Dam, ca 1913 , Courtesy GreetingsFromSiouxFalls.com