Your Dam Your Responsibility (PDF~1.2MB)

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Appendix B
Problem Possible Causes and
Potential Harm
Livestock Traffic Cause:
1. Excessive travel by livestock
especially harmful to slope
when wet.
Harm:
1. Creates areas bare of erosion
protection grass cover.
2. Causes erosion channels.
Allows water to stand. Area
susceptible to drying cracks.
Pest Animal Activity Cause:
1. Over-abundance of animal
pests.
2. Favourable habitat or
burrowing conditions at dam.
Obscuring Vegetation
and trees
Harm:
1. Burrows can substantially
reduce leakage path, leading
to piping failure.
Cause:
1. Natural vegetation (self-
sown).
Harm:
1. Large tree can die. Roots can
then create seepage paths.
2. Bushes can obscure visual
inspection.
3. Provides habitat for rodents.
4. Trees can fall, creating holes in
crest or side slopes.
Action Required
Action:
1. Fence livestock outside
embankment area.
2. Repair erosion gully.
3. Recover with grass for
protection.
Action:
1. Control pests to prevent
additional damage.
2. Provided the diagnosis is
correct, determine the extent
of burrowing and backfill with
compacted clay, working from
upstream to downstream
as far as possible. If there
is any doubt at all as to the
cause of these burrows, seek
professional advice before any
remedial action.
Action:
1. Remove large deep rooted
trees and shrubs on or near
embankment.
2. Properly backfill void left by
tree stump.
3. Control all other vegetation
on the embankment that
obscures visual inspection.