Download or read book National Dam Safety Program. Ischua Creek Watershed Dam Number 1 (Inventory Number N.Y. 583), Allegheny River Basin, Cattaraugus County, New York. Phase I Inspection Report written by Robert J. Farrell and published by . This book was released on 1981 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam consists of a zoned earthfill embankment with an earthfill cutoff trench below; a principal spillway with a reinforced concrete riser structure and outlet pipe; and two vegetated earth channel emergency spillways located to the north and south of the dam embankment. The length of the dam embankment is approximately 490 ft. The length of the dike is approximately 1300 ft. The two emergency spillways total 500 ft. in weir length. Using the Corps of Engineers screening criteria for review of spillway adequacy, it has been determined that the dam would not be overtopped under full PMF conditions. The PMF routed through the reservoir required 98 percent of the spillway outflow capacity. The spillway capacity is, therefore, judged as adequate.