PROJ00474

• Contract/PO #: FS0005x
• Contractor Name: Central Colorado Water Conservancy District
• County: El Paso
• Loan Projects - Doc Type: Feasibility Study

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Page 2

Eootleg Reservoir Dam
October 21, 1982

Extensive rodent activity was noted beneath the concrete facing at a point approxi-
mately 500 feet to the right of the left end of the con'crete facing. At this point I
an apparent large rodent excavation exists causing a collapse of the over-lying
concrete facing. This collapsed area is just below the mid-slope of the upstream
facing and is approximately 10 feet in diameter located approximately 12 vertical
feet al:ove the upstream toe. Additional rodent holes were noted under the up-
stream facing approximately 50 feet farther to the right. These holes do not appear
to I:e as large and the concrete upstream facing has not collapsed in these areas.

Near the left portion of the dam I where the embankment section is quite shallow I
the concrete facing has been terminated and the upstream slope consists of a man-
made embankment with an upstream slope of approximately 3:1 protected by grass
covering.

Genera lly,. the upstream face of the Bootleg Dam is in poor condition but appears
to be serviceable for the short durations of storage which occur during a flooding
incident. As evidenced during the September 14 flood, this reservoir may be
dra ined norma lly in a maximum time of approximately 3.5 days. If necessary I
the outlet gates on this structure could be opened further to accelerate the rate
of drawdown.

Crest -- The crest of the dam is extremely variable in width and in elevation over
the length of the structure. Tne crest elevation of the dam undulates as mu.ch as
3 feet vertica lly over the length of the structure. Generally I the portion of the dam
near the right abutment is somewhat higher than the remaining portions of the struc-
ture. In that area protected by upstream concrete facing, the lowest point of the
crest is noted near the center of the dam. The west or left end of the dam beyond
that portion of the structure protected by the concrete facing is approximately 2
feet lower in elevation than the upstream shoulder of that portion of the dam protected
by the facing. As can be evidenced in past pictures of this dam, the crest of. the
dam's slopes noticeably downward toward the downstream shoulder of the crest
with the high point of the crest being at the upstream shoulder I the intersection
of the upstream facing and the crest. It appears that this severe gradient in the
downstream direction on the crest of the dam may have been caused both by sur-
face run-off and wind erosion. No effort has been made to maintain this portion
of the structure over the past several years. Generally, this portion of the struc-
ture appears to be in a poor, unmaintained condition, but appears to be service-
able for the purpose of flood water retention.

Downstream Slope -- That porti<;m of the downstream slope to the left of the out-
let structure is fa irly uniform over the length of the dam being at a slope of
approximat~lY 2.5:1. Extensive cattle traffic on the downstream face of this dam
has caused several cattle paths to form resulting in benching and slight scarping
of the downstream face. Those portions of the downstream face unaffected by
cattle traffic are protected by an adequate growth of vegetation, protecting the
dam against adverse erosion by surface runoff and wind. The Denver-Hudson Canal