Minor cracking and/or Watch Immediately install measuring device to Crack Size, location movement. monitor movement. Monitors, Cracking or movement stakes, tape measure of concrete structure Significant cracking Watch Initiate 24-hour surveillance. Lower burlap on Burlap, rockfill, Size, and/or movement. upstream face of crack to reduce flow of soil dozer, shovels location, flow particles. Dump rockfill downstream of rate moving concrete structure monolith to resist the movement. Serious cracking and/or Possible failure Continue monitoring and remedial action as Dozer, rockfill, Size, movement described above. burlap, crack movement, monitors flow rate Major cracking and/or Imminent Downstream evacuation. Continue monitoring Dozer, shovels, Size, movement failure and remedial actions as described above. rockfill location, flow rate Whirlpool in the lake Imminent Downstream evacuation. Attempt to plug the Dozer, source Size, Upstream in the vicinity of the Failure entrance of the whirlpool with riprap from the of earthfill, location, flow embankment slope of the embankment. Search sandbags, filter rate Whirlpool downstream for an exit point and construct a cloth, straw, ring dike to retard the flow of soil particles. rocks Structural member of Possible failure Initiate 24-hour surveillance. Immediately Crane and Type of a gate or gate operator place stop logs in front of gate and initiate welder problem, Broken gate broken or severely necessary actions to get gate repaired. location damaged so as to prevent operation of the gate level rising and rain Watch Initiate 24-hour surveillance of lake level and Lake level, Rapidly continuing rainfall. rainfall rising lake Water flowing over Possible failure Downstream evacuation. Continue Lake level, the dam and lake monitoring. rainfall Dam being continuing to rise overtopped
Cracking or movement of concrete structure Minor cracking and/or movement. Watch Immediately install measuring device to monitor movement. Crack Monitors, stakes, tape measure Size, location Significant cracking and/or movement. Watch Initiate 24-hour surveillance. Lower burlap on upstream face of crack to reduce flow of soil particles. Dump rockfill downstream of moving concrete structure monolith to resist the movement. Burlap, rockfill, dozer, shovels Size, location, flow rate Serious cracking and/or movement Possible failure Continue monitoring and remedial action as described above. Dozer, rockfill, burlap, crack monitors Size, movement, flow rate Major cracking and/or movement Imminent failure Downstream evacuation. Continue monitoring and remedial actions as described above. Dozer, shovels, rockfill Size, location, flow rate Upstream Whirlpool Whirlpool in the lake in the vicinity of the embankment Imminent Failure Downstream evacuation. Attempt to plug the entrance of the whirlpool with riprap from the slope of the embankment. Search downstream for an exit point and construct a ring dike to retard the flow of soil particles. Dozer, source of earthfill, sandbags, filter cloth, straw, rocks Size, location, flow rate Broken gate Structural member of a gate or gate operator broken or severely damaged so as to prevent operation of the gate Possible failure Initiate 24-hour surveillance. Immediately place stop logs in front of gate and initiate necessary actions to get gate repaired. Crane and welder Type of problem, location Rapidly rising lake level rising and rain continuing Watch Initiate 24-hour surveillance of lake level and rainfall. Lake level, rainfall Dam being overtopped Water flowing over the dam and lake continuing to rise Possible failure Downstream evacuation. Continue monitoring. Lake level, rainfall
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