National Dam Safety Program. Assunpink Creek Dam Number 20 (NJ00552), Delaware River Basin, Assunpink Creek, Mercer County, New Jersey. Phase I Inspection Report.

Abstract

Abstract : Based on visual observations made during the inspection, information provided by the New Jersey Department of Environmental Protection (NJDEP), the Soil Conservation Service (SCS), the Mercer County Parks Commission (MCPC), the Owners and conversations with the representatives of SCS and MCPC, Assunpink Creek Dam No 20 is considered to be in overall good condition. The dam provides flood control and provides an impoundment for recreation. The dam is a zoned earth embankment approximately 3,830 feet long with a maximum height of about 26 feet. The width of the crest of the dam is 15 feet and both the upstream slopes are 3H:1V. The spillway is a three stage system. The low stage principal spillway consists of a 4-foot wide by 12-foot long and 11.5 foot high reinforced concrete intake riser which outlets into a 4-foot diameter, 81.5 foot long prestressed reinforced concrete pipe. The principal spillway pipe outlets through the headwall of the intermediate stage principal drop spillway. The intermediate stage reinforced concrete principal drop spillway is 90 feet long, 17.5 feet high with a 48.5 foot-long discharge apron and a three foot high end sill at the downstream end of the apron. The high stage reinforced concrete auxiliary drop spillway is 250 feet long, 19.5 feet high with a 38.5-foot long discharge apron and a 2.25-foot high end sill at the downstream end of the apron. A stilling basin of approximately four acres is located immediately downstream of the principal and auxiliary drop spillways. The stilling basin outlets into the natural channel of Assunpink Creek about 500 feet downstream of the spillways.