U.S. Fish & Wildlife Service Low Hazard Dams - Association of State ...

damsafety.org

U.S. Fish & Wildlife Service Low Hazard Dams - Association of State ...

STANDING OPERATING PROCEDURESProblemProbable Cause and PossibleConsequencesRecommended ActionsNatural vegetation in area. Largetree roots can create seepage paths.Large trees can blow over duringstorms and damage dam or causebreach. Bushes can obscure visualinspection and harbor rodents.Overabundance of rodents. Animalburrowing creates holes, tunnels,and caverns. Certain habitats, suchas cattail-filled areas and trees closeto the reservoir encourage theseanimals.Can reduce length of seepage pathand lead to piping failure. If tunnelruns through most of the dam, it canlead to collapse.Excessive travel by livestockespecially harmful to slope whenwet.Creates areas bare of erosionprotection and causes erosionchannels. Allows water to stand.Area susceptible to drying cracks.1. According to the FWS TreeRemoval Guidelines (SeeAppendix F), any trees growingon the upstream slope that areless than 2 inches in diametershould be cut and treated.Trees growing on thedownstream slope that aregreater than 2 inches should beremoved. Trees growing on thecrest, downstream slope and 20feet beyond the toe of the damthat are less than 6 inches indiameter should be cut andremoved. Trees growing on thecrest, downstream slope and 20feet beyond the toe of the damthat are greater than 6 inches indiameter should be removed.2. Control vegetation on theembankment that obscures visualinspection.1. Control rodents to prevent moredamage.2. Backfill existing rodent holes.3. Remove rodents. Determine exactlocation and extent of tunneling.Remove habitat and repairdamages.1. Fence livestock outsideembankment area.2. Repair erosion protection, i.e.riprap, grass.Revision No. 0B-5 October 2008

More magazines by this user
Similar magazines