400 East Court Avenue | Suite 140 | Des Moines, IA 50309

Gilbertville Bridge Widening

LocationBlack Hawk County
  • Project

    768’ x 24’ Continuous I-Beam Bridge Widening to 30’ Roadway with 8’ Sidewalk.

  • Cost

    $1.2 million


Several options were considered to upgrade the existing 40-year-old bridge and link it to the county bike trail system. An innovative design reduced costs and construction time while maintaining traffic through the site:

  • Re-use of existing pier stems and footings and adding post-tensioned caps eliminated cofferdams and expensive new pier construction.
  • Respacing/strengthening existing beams and adding new heavy rolled sections improved load capacity, dynamic response and bridge width.
  • Staged construction allowed traffic to be maintained. The sidewalk was designed for temporary vehicle traffic during Stage II, with open concrete rail retrofit after 2-way traffic was restored.

With appropriate maintenance, the new high-density concrete deck and AASHTO-rated railing upgrade will serve Black Hawk County well into the 21st Century.

>>Download a pdf of this project sheet