Conflicting Design Requirements and Ice Loading Create an Emergency Response at a Dam

Pikes Creek Dam was initially constructed for water supply between 1908 and 1911 by the Spring Brook Water Company. Located in Luzerne County, Pennsylvania, the dam is on Pikes Creek, about two miles northwest of Ceasetown. Spillway capacity has been an issue since 1917. The spillway was significantly enlarged throughout the 1920s and again in the early 1990s before the dam was acquired by Pennsylvania American Water (PAW) in 1996.

The Pennsylvania Department of Environmental Protection (PADEP) classifies the dam as a high-hazard structure. The dam is required to pass the Probable Maximum Flood (PMF). After acquiring the dam, studies completed by PAW demonstrated that the spillways were incapable of passing the PMF.

A comprehensive rehabilitation of the dam was completed in 2017-2018. The centerpiece of the repair consisted of installing Hydroplus Fusegates within the 250-foot width of the existing auxiliary spillway. The Hydroplus Fusegates were designed to provide PMF capacity to bring the dam into compliance with current PADEP regulations.

In the winter of 2019, increasing leakage at the auxiliary spillway prompted aFn emergency response by PAW (owner), Gannett Fleming (engineer), Hydroplus (fusegate developer), and KC Construction (contractor). The amount of leakage and limited capacity of the downstream watercourse required immediate surveillance, evaluation of the ice loading on the gates, and the development of short- and long-term solutions to prevent overtopping of the downstream state road, as shown in Figure 1.

The Pikes Creek Dam project is the first known installation of Hydroplus Fusegates to experience rotation due to ice loading. Therefore, a significant portion of the paper is also dedicated to ice loadings on fusegates and the solutions developed to prevent further incidents of rotation due to ice loads.