The Manette Bridge replaced an 80-year-old, 1500 feet long (460 m) design of which the community was fond, requiring a sensitive approach to the new design that still provided durability and cost effectiveness. Precast concrete parabolically haunched spliced girders helped achieve these goals.
The new bridge was constructed approximately 3 feet (0.9 m) from the existing bridge, allowing it to remain open to traffic. The new bridge overlapped the existing one on the west end, requiring a short closure, which was minimized by the quick erection of the precast concrete girders.
The parabolic shape created varying web and bottom-flange thicknesses through the bridge’s length, adding visual interest. All of the segments of each type of girder are the same, providing economy in casting.
Columns were designed as classic forms rising outside the superstructure to embrace pedestrian overlooks. Girder closures were detailed with nautical themes and traditional-looking brackets.
The bridge’s appearance was enhanced by architectural details created from extensive public input. In addition to the parabolic girders, aesthetic details include a compass-rose motif on the piers that alludes to navigation and a deep-green railing, which recalls the replaced steel truss.