A Boil on the back side of salt fork lake dam, what a pain in the...

At 11:00 am on February 15, 2005, Ohio’s Dam Safety Engineering Program (DSEP) received a call from the maintenance manager for Salt Fork State Park. A large seepage boil was noted at the downstream toe of the 61-foot-high state-owned Salt Fork Lake Dam. Two DSEP engineers were dispatched to the site to initiate emergency procedures. The boil was located 8 feet downstream of the toe of the dam. It was about 4 feet in diameter and about 2 feet deep. There was some evidence of a classic sand cone of material around the boil; however, most of it appeared to have been washed away by the flow coming from the boil. DSEP staff and park personnel proceeded to construct a sandbag ring levee around the seepage boil. Once the ring levee was constructed, a v-notch weir was installed to monitor the flow from the boil. The flow was determined to be about 70 gallons per minute. Salt Fork Lake Dam was constructed in 1968, on a 100-foot-thick natural deposit of sand and gravel in eastern Ohio. The dam impounds a beautiful 3010-acre lake in Ohio’s largest state park. The lake is used for recreation and was also designed to be a water supply source. Salt Fork Lake Dam is a Class I dam (high hazard) based on its size and potential downstream hazard. Located immediately downstream is Interstate 77, and further downstream are approximately 200 people between the dam and the USACE flood control structure - Wills Creek Dam. The paper and presentation will elaborate on DSEP’s emergency response procedure and the continuing activities and investigations at Salt Fork Lake Dam. 14 pp., 8 references.