Electric Lake Dam - Physical Modeling of the Morning Glory Outlet Works

Abstract Only - The Electric Lake Dam, owned and operated by PacifiCorp, impounds a water supply reservoir on Huntington Creek located approximately 26 miles northwest of Huntington, Utah. The dam is comprised of a 31,500 ac-ft reservoir, an approximately 230-ft high embankment dam, and outlet works consisting of a morning glory spillway, intake tower, valve chamber, outlet conduit, and an impact-type energy dissipation basin.

As part of the dam safety evaluations PacifiCorp is conducting for the Electric Lake Dam, Northwest Hydraulic Consultants Ltd. was retained to construct and test a 1:14 scale physical model of the existing morning glory outlet works to evaluate the outlet works’ hydraulic performance and assist with the assessment of risk potential associated with the dam’s hydrologic Potential Failure Modes. The physical model served as a valuable tool in developing rating curves for outlet works and identifying the potential for unstable flow conditions and cavitation within the outlet works.