_GENERAL DOCUMENTS - C1981017 ‎(165)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Permit Index Doc Type: General Correspondence
• Media Type: D
• Archive: No

I consulted with the Denver office. We then removed the single
expanded metal plate from the channel. I contacted Dr. Jim
Pendleton in Denver. Jim advised that in his opinion, the best
course of action was to ensure the most expeditious movement of
materials through the channel. Entrainment of anything over a silt
sized particle was unadvisable. This degree of movement would
indicate that no traps be installed in the channel . Jim advised
that there was a low chance for failure this year, as it has taken
15 to 20 years to wear as much as it has. Jim thought that the
worst case would be that a hole would be punched in the base and a
wetting front under the concrete would develop in the underlying
material. The overhanging portion of the flume structure has the
metal 8 foot culvert in it, and would not experience the potential
for puncture. It was agreed that it would be a waste of money and
effort to proceed further at this point. Two other options were
discussed, however. We discussed securing the expanded metal with
straps which would extend across the channel and up and over the
sides. The drawback to this is that the lengths of steel required
are quite large. If one were to fail, blockage of the concrete
channel or of the 8 foot culvert could occur, resulting in
significant environmental harm. The other option would be to pour
a concrete layer in the eroded portion of the channel . It was
agreed that this was not viable at the present time given the
lateness of the season, the expense of diverting the flow during
pouring of the concrete, the low potential for failure this year
and the idea that Dutch Creek would be re-routed in the future.
I contacted David Bucknam late in the day and asked for his input.
David felt that it was possible that if the anchors had been
epoxied, that the expanded metal plates could have worked. If one
had failed, perhaps it would have simply washed through the culvert
into Dutch Creek. However, David stated that he was comfortable
with the decision, given Jim Pendleton's input.
Mike Frick was advised of the need to not install the expanded
metal plates. He agreed that this seemed to be a sensible course
of action as he had doubts that the plates would remain in place.
He further stated that he thought that the channel would remain in
tact through next years runoff. He advised that there would be no
charge to the State for this work.