The East Caley Drive crossing of Piney Creek in Centennial, Colorado, had been a low water crossing since the 1970s, but it had increasingly become a safety hazard. The Urban Drainage and Flood Control District and the Southeast Metro Stormwater Authority retained Ayres Associates to evaluate alternatives for the crossing and to design stream stabilization and a bridge at East Caley Drive.
The project team held public meetings with residents to develop the selected alternative for the crossing and to coordinate equestrian access. The project resulted in a concrete box girder bridge and associated road improvements and approximately 600 linear feet of stream stabilization in a sand bed channel. The bridge was designed to pass the 100-year flood event and to maintain the aesthetics of nearby bridges while keeping the rural feel of the neighborhood. The stream stabilization included a stepped grouted boulder drop structure upstream of the bridge and grouted boulder walls varying in height from 2 to 12 feet lining portions of the stream banks throughout the project. Ayres also provided full-time construction observation services.
The Colorado Association of State Floodplain Managers awarded the project its 2011 Grand Award for Engineering.