National Dam Inspection Program Wildwood Lake Dam Ndi Id Number Pa 00157 Der Id Number 64 30 Delaware River Basin Ariel Creek Wayne County Pennsylvania Phase I Inspection Report

Based on visual inspection, available records, calculations, past operational performance, and according to criteria established for these studies, Wildwood Lake Dam is judged to be in fair condition. Based on the size and hazard classification of the dam, the Spillway Design Flood (SDF) at the dam varies between 1/2 the Probable Maximum Flood (PMF) and the PMF. Based on the downstream conditions, the selected SDF is the PMF. Under existing conditions, the spillway will pass about 48 percent of the PMF without overtopping of the dam. It is judged that the dam could withstand the depth and duration of overtopping that would occur during the 1/2 PMF. If the low areas on the top of the dam were filled to the design elevation, the spillway would pass about 62 percent of the PMF without any overtopping. For either condition, the spillway capacity is rated as inadequate.

The visual inspection and review of available design and construction information indicate that Lake Quinn Dam is in fair condition. Deficiencies noted during the inspection included the lack of functional drawdown facilities and minor seepage through the masonry near the right abutment. Based on the size and hazard classification of the dam, the recommended Spillway Design Flood (SDF) varies between 1/2 the Probable Maximum Flood (PMF) and the PMF. The 1/2 PMF has been selected as the SDF due to the size of the dam and reservoir, and the downstream conditions. The hydrologic and hydraulic computations indicate that the combination of reservoir storage and spillway discharge capacity will pass only 3 percent of the PMF without overtopping the dam. Overtopping the dam could cause failure, which would lead to a significant increase in downstream loss of life and property damage. Therefore, the spillway for Lake Quinn Dam is considered to be seriously inadequate, and the dam is judged to be unsafe, non-emergency.

Based on available records, visual inspection, calculations, and past operational performance, Lake Paupackan Dam is judged to be in fair condition. Considering the size and hazard classification of the dam, the recommended Spillway Design Flood (SDF) varies between the 1/2 Probable Maximum Flood (PMF) and the PMF. The 1/2 PMF was, in this case, selected as the SDF. The spillway and reservoir, under existing conditions, will pass approximately 19 percent of the PMF before overtopping of the dam occurs. The spillway is, therefore, rated as inadequate.

Starlight Lake Dam is located on an unnamed tributary of Shehawken Creek in Buckingham Township, Wayne County, 0.2 mile north west of Starlight, Pennsylvania. The original purpose of the impounded water was for ice harvesting and recreation. Presently, the lake is being used for recreation. The overall appearance of the dam is poor. Locations of observed deficiencies are shown on the General Plan. The profile and typical sections of the dam are presented and are based on field survey made on the days of inspection. The survey datum for this inspection is elevation 1355 feet above mean sea level for the normal water surface of the lake at the top of the spillway flashboard. On the inspection date (12/11/1980), the lake level was approximately at elevation 1355.5 or 0.5 foot above the spillway flashboard. Deficiencies observed during the field inspection are described, visible features are depicted in photographs.

Lower Twin Lake Dam is located on a branch of Kinneyville Creek in Preston Township, Wayne County, Pennsylvania. The overall appearance of the dam is poor. Location of observed deficiencies are shown on the General Plan presented. The profile and typical sections of the dam are presented and are based on field survey made on the day of inspection. The survey datum for this inspection is elevation 1495 feet above mean sea level for the normal water surface of the lake. On the inspection date (12/02/80), the lake level was approximately at elevation 1495, which is 1.5 feet below the low point on the dam crest. Deficiencies observed during the field inspection are described below, and are further illustrated. Visible features are depicted in photographs presented.

Greene-Dreher Dam is a 20-foot high earthern embankment, 1,000 feet long which impounds a 152 acre-foot flood water retention pool. Total estimated volume of fill is approximately 30,000 cubic yards. The zoned embankment was constructed on natural soils without a cutoff trench or a grout curtain. The embankment contains three material zones; Zone 1, a relatively impervious core of silt and and silty sand; Zone 2, composed of silty gravel and silty sand; and an outer shell of Zone 3 material, described as rock larger than 6 inches in diameter. The embankment crest is 12 feet wide at a design settled elevation of 2,036 feet, and both upstream and downstream slopes are 3H:1V. The downstream section of the embankment contains a filter blanket approximately 2 feet thick, 30 feet wide and 320 feet long. The filter blanket is drained by a 6-inch diameter perforated corrugated metal pipe connected to a 6-inch diameter pipe which outlets adjacent to the principal spillway outlet.