All three improvements are vital to preserve the integrity and safety of State Route 89A. The highway was built in a canyon with a lot of rock-cut faces, which erode over time due to weather conditions. This leads to large rocks, sediment and other debris on the roadway, which creates significant safety and maintenance issues. The improvements include:
- Rockfall Mitigation
- Drainage & Sediment Control
- Pumphouse Wash Bridge Rehabilitation
The Rockfall Mitigation improvement will help reduce the potential of large rocks falling onto the roadway at two locations along SR 89A. There have been several previous emergency closures due to rockfall events blocking the roadway.
The Drainage & Sediment Control improvement will reduce erosion to preserve deteriorating slopes and reduce downstream pollution as well as minimize or prevent future unplanned closures of SR 89A due to sediment or rocks blocking the roadway. In addition, the Pumphouse Wash Bridge Rehabilitation improvement is needed to maintain the structural integrity of the bridge, which is past its service life.
In summary, the improvements are needed to continue maintaining safety and access for motorists along SR 89A in Oak Creek Canyon.