National Dam Inspection Program. PA-484 Dam (NDI-ID-PA-489) (DER ID-63-72) Ohio River Basin, Tributary of Harmon Creek, Washington County, Pennsylvania. Phase I Inspection Report.
D'APPOLONIA CONSULTING ENGINEERS INC PITTSBURGH PA
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The PA-484 Dam is one of the 14 flood control projects in the Harmon Creek watershed. The dam consists of an earth embankment approximately 320 feet long, with a maximum height of 67 feet from the downstream toe and a crest width of 14 feet. The flood discharge facilities for the dam consist of a drop inlet primary spillway located at the center of the embankment and an emergency spillway on the left abutment looking downstream. The primary spillway structures consist of a two-stage reinforced concrete riser, a 24-inch-diameter reinforced concrete conduit and a reinforced concrete impact basin at the downstream end of the outlet conduit. The emergency spillway is a 50-foot-wide trapezoidal earth channel excavated into the left abutment. The reservoir outlet for the dam consists of a 12-inch steel pipe extending from the upstream toe of the dam to the drop inlet structure. Flow through the reservoir outlet is controlled by a manually operated sluice gate located in the drop inlet structure. The dam is located on an unnamed tributary of Harmon Creek approximately one mile west of Hanlon Station in Hanover Township, Washington County, Pennsylvania.
- Civil Engineering