Engineered Solutions: New Bridge in Hawaii Forest Replaces Roadway Prone to Flooding
Acrow Bridge designed and provided a permanent bridge to Mocon Construction for vehicle and pedestrian use in the Keahua Arboretum in the Keahua State Forest in Kauai, Hawaii. Planted with native plants and vegetation introduced by the University of Hawaii, the arboretum also is enjoyed for picnicking, swimming, hiking, biking and horseback riding.
The original route, a concrete roadway, had sunk over time and flooded after heavy rains. Safe passage over the Keahua Stream wasn’t always possible in this remote but highly traveled area. The decision was made to construct a permanent bridge at the site, along with new roadway alignment and a drainage culvert with inlet and outlet.
The decision to use an Acrow structure made sense for the tight construction zone, where Acrow modular components can be installed more easily than most other styles of bridges in constrained build areas. The 110-foot-long by extra-wide single-lane bridge has a coated deck and a special 1-meter-wide sidewalk that was specified by the Hawaii Department of Land and Natural Resources (DLNR).
The bridge, which opened in April 2017, is owned by Hawaii DLNR and will be virtually maintenance-free with a lifespan of 75 years or more. The design engineer was Kai Hawaii Inc.
“It is gratifying that our bridge is being utilized to provide safe crossing for visitors to this amazing recreation area,” says Bill Killeen, president and CEO of Acrow Bridge.