National Dam Inspection Program. Johnson's Pond (NDI-ID Number MD-11), Wicomico River Basin, Wicomico River, Wicomico County, Maryland. Phase I Inspection Report,

Abstract

The dam consists of a concrete and steel ogee spillway, wingwalls, and a clay fill embankment constructed on either side of the spillway. Including the lengths of clay fill embankments shown on the contract drawings of the dam, the total length of the dam is 580+ feet. the Concrete and steel structure is comprised of a 300 foot long ogee spillway with wingwalls at the left and right abutments. According to the dam crest survey, the lowest point along the clay fill is elevation 14.5 and is located adjacent to the right wingwall. The crest elevation of the ogee spillway is +11.1, and a 30 foot long notch with a crest elevation of 10.6 is located in the middle of the spillway. Three sluice gates are located in the spillway directly below the notch. According to the hydrologic and hydraulic analyses, the Johnson's Pond embankment will overtop by 0.4 foot for a duration of 10 hours during a flood equaling 50 percent of the Probable Maximum Flood (PMF). The analyses indicate that the Johnson's Pond spillway can pass approximately 43% of the PMF before overtopping commences.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1980
Accession Number
ADA091268

Entities

People

  • Edward J. Zeigler

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Concrete
  • Construction
  • Dams
  • Drainage Basins
  • Embankments
  • Engineering
  • Engineers
  • Inspection
  • Maryland
  • Materials
  • Plastic Explosives
  • Retaining Walls
  • United States
  • Visual Inspection
  • Warning Systems
  • Water
  • Water Resources

Readers

  • Hydraulic Engineering.
  • Hydrologic Risk Analysis and Mitigation.