The Foster Joseph Sayers Dam helps protect the local habitat and water quality of Bald Eagle State Park’s reservoir in Howard, Pennsylvania – a well-known spot for fishing, boating and swimming. But concrete erosion in the dam’s stilling basin threatened to compromise the integrity of the spillway. Without repair, this could lead to failure of the spillway and ultimately the dam, causing catastrophic flooding in the communities downstream.
That’s why the U.S. Army Corps of Engineers (USACE) called on our Highway and Bridge crew to repair the damage to the stilling basin caused by riprap entrainment. Collaborating with the engineer, CDM Smith, we designed a plan to replace the damaged rebar and concrete and install an additional silica fume concrete wedge to prevent riprap and debris from being trapped and causing future damage to the stilling basin.
Before work could begin, our crews had to figure out how to maintain the water flow to Bald Eagle Creek downstream while diverting it from our work area. The USACE allowed only one-hour shutdowns of the outflow, as cutting off the water any longer would negatively affect the creek. Because of the dam’s unique design, crews had to install an eight-foot diameter conveyance pipe to carry the water above our work area – a set-up that was the first of its kind for our team. We installed the conveyance pipe and hanger system along with the connecting bulkhead, which was fabricated by our Industrial team.
Our next challenge was to dewater the stilling basin and relocate thousands of fish. We utilized special fencing to carefully herd the fish, remove them with nets into a large container, and safely relocate them from the stilling basin with a crane. Then we were able to move forward with dewatering the work area.
From there, we completed hydrodemolition removal of all damaged concrete in the stilling basin, installed new rebar, and placed and cured the new silica fume concrete including the new wedge. All of our work was completed by early January, thanks to this crew’s comradery, can-do attitude and drive to keep this project on track. Thank you for all of your hard work – Ryan, Chris, Shawn, Curt, Brett, Jay, Travis, Jim and Jon!