Honey Lake Dam, is a 1,100 foot long earth embankment dam, with a maximum height of approximately 22 feet. The primary spillway is a 70 foot long, Type B, drop structure. The crest elevation of the spillway is 144.5 feet. The reinforced concrete spillway headwall is supported by concrete buttresses that extend downstream to the longitudinal sill of the concrete downstream apron. The downstream apron consists of a reinforced concrete floor with two longitudinal sills and a 16 inch high transverse end sill. The low level outlet gate is located on the left (eastern) sidewall of the primary spillway structure. The low level outlet consists of a 24 inch reinforced concrete pipe (RCP) that was installed on a concrete cradle that extends upstream into the lake and outlets onto the downstream apron. The dam is classified as Class I, High Hazard with the Spillway Design Storm (SDS) being the Probable Maximum Precipitation (PMP) storm event.
FPA was retained by the NJ DPMC to prepare a comprehensive dam investigation report including stability analyses, and a hydrologic and hydraulic analysis to determine the preferred alternative to rehabilitate the dam. FPA subsequently prepared final design plans and specifications to modify the spillway structure to and place Roller Compacted Concrete (RCC) on the crest and downstream slope of the embankment to accommodate the Spillway Design Flood (SDF), which is considered the Probable Maximum Precipitation (PMP) event. Our scope of services also included obtaining a Dam Safety Permit, a General Permit No. 18 and Soil Erosion and Sediment Control Plan certification from the local Soil Conservation District.