Milton-Freewater Nursery Bridge Drop Structure Emergency Repair/Rehab Dam Projects

The work on this project consisted of two major features of work.  These were armor plating the base of a concrete spillway and installing a new gabion structure downstream of an existing concrete stilling basin.  The work involved concrete removal; drilling and installing epoxy anchors for the armor plates; installing new stainless steel armor plates; grouting the void behind the plates; and installation of joint sealant between the plates.  Installation of the gabion structure required clearing and grubbing; excavation and finish grading; installation of gabion baskets; shotcreting over the gabion baskets; and installation of riprap downstream of the new gabion structure.  This work all was completed in the Walla Walla River during a tight in-water work window.  Constant dewatering activities were required to complete all phases of work.