National Dam Safety Program. Upper Keswick Dam (NJ-00047), Atlantic Coastal Basin, Wrangel Brook, Ocean County, New Jersey. Phase I Inspection Report.
NEW JERSEY DEPT OF ENVIRONMENTAL PROTECTION TRENTON
Pagination or Media Count:
Upper Keswich Dam is an earthfill dam with a paved roadway along the crest and a concrete capped timber drop inlet as a spillway. The overall condition of the dam is good. There are no major signs of distress or instability in the embankment. Minor seepage was observed at three different locations along the downstream toe. One location was to the left of the downstream channel and the others at each end of the dam. The low-level outlet was not open at the inspection and is not used. The hazard potential is rated as high. Upper Keswick Dam is considered inadequate in view of its lack of spillway capacity to pass the SDF 12 PMF without overtopping the dam. The spillway is capable of passing a flood equal to 21 percent of the PMF 42 percent of the 12 PMF, and is assessed as inadequate. At present, the engineering data available is not sufficient to make a definitive statement on the stability of the dam, but based on the findings of the visual inspection, the preliminary assessment of static stability is that it is satisfactory.
- Hydrology, Limnology and Potamology
- Civil Engineering