Structural Engineering

Architectural Building DesignBridges & CulvertsCommercialIndustrialRetaining Structures

Airport Road over Branch Platte River

IIW balanced an endangered species habitat and bridge size and placement when replacing a bridge that had been deemed functionally obsolete, narrow, and structurally deficient along Airport Road in Grant County, Wisconsin. To improve the geometrics of the roadway approached, IIW designed the replacement bridge on a relocated alignment over a Branch of the Platte […]

D-22 Over Dry Creek Box Culvert

Buchanan County called on IIW to evaluate a deficient, narrow bridge that faced growing traffic counts and was adjacent to an active railroad. IIW evaluated replacement options that provided solutions which did not impact adjacent railroad or encroach on the railroad right-of-way. IIW performed a hydraulic analysis to determine structure options, selecting a reinforced concrete […]

Lower Bee Branch Creek Restoration

Located in the north-central portion of Dubuque, the Bee Branch drainage basin has a long history of extreme flooding. The Bee Branch Restoration Project aims to change that. In the initial phase, IIW designed two continuous concrete slab bridges that met the community’s goals for flood prevention and aesthetic appeal. Early in the project, leaders […]

North Cascade Road over the South Fork Catfish Creek

IIW led the emergency replacement of the North Cascade bridge after it was washed out by a summer storm in Dubuque, Iowa. IIW’s engineering team conducted a hydrologic and hydraulic analysis to determine the optimal type, size and location of the bridge over South Fork Catfish Creek. The mapped floodplain and detailed flood study led […]

Upper Bee Branch Creek Restoration

The City of Dubuque’s Bee Branch Creek Restoration Project was the largest capital improvement project in the City’s history, serving as both a watershed solution and a catalyst for neighborhood reinvestment and revitalization. The design takes former industrial, commercial, and residential properties and creates an open waterway with a linear park—complemented by highly-visible bridge, culvert, […]

Water Street over Wapsipinicon River

IIW’s work on the Water Street bridge over the Wapsipinicon River in Quasqueton, Iowa, began with the evaluation of a series of rehabilitation options. IIW helped city and county officials understand the costs of structure repair compared to a new structure. Upon the review of the widening options, the City and County chose to replace […]