NPDP Dam Dictionary

Browse by Letter:
All  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  


Term AKA Definition
Mitigation Action taken to avoid, reduce the severity of, or eliminate an adverse impact.
Modification/Repair Type A data field used to summarize the type of modification (change to a dam) or repair (work performed to remedy damage that occurred to a dam or its apputenances) that was implemented.
Modified homogeneous earthfill dam A homogeneous earthfill dam that uses pervious material specially placed in the embankment to control seepage. See embankment dam. Modified Mercalli scale. An earthquake intensity scale which has twelve divisions
Modified Mercalli scale An earthquake intensity scale which has twelve divisions ranging from I (not felt by people) to XII (nearly total damage). For more information on the modified Mercalli scale, visit the U.S. Geological Survey National Earthquake Information Center.
Moisture content water content The ratio of the weight of water in a soil sample to the weight of the dry soil, expressed as a percentage. See optimum moisture content.
Monomictic lakes Warm- water lakes which turn over annually, usually in winter, and where the temperature never falls below 4 degrees C.
Morning glory spillway A circular or glory hole form of a drop inlet spillway. Usually free standing in the reservoir and so called because of its resemblance to the morning glory flower.
MS connectors Surface delays for use when shooting with detonating cord.
Multiple arch dam A buttress dam, the upstream part of which comprises a series of arches.
Multiple-purpose reservoir A reservoir planned to operate for more than one purpose.
Multipurpose dam A dam constructed for two or more purposes (e.g. storage, flood control, navigation, power generation, or recreation.)