BOARD02386

• Board Meeting Date: 3/8/1972
• Description: Agenda or Table of Contents, Minutes, Memos
• Board Meetings - Doc Type: Meeting

I

Based on the current analysis. it appears
that of the seven dams that we investigated
that only the West Bijou Creek. site "A."
would be justified under current interest rates
and the anticipated increase to 7 percent.

There are two columns here. One column
shows the benefit-cost ratio with Narrows and
the benefit-cost ratio without Narrows. This
is not the diversion channel. This is the
dam itself. The difference between the two
numbers is with the Narrows in operation there
will be a more intensive use of land and the
flood control benefits will be greater than
without Narrows. There is also a hydrologic
relationship here that accounts for some of
this difference. The analysis indicates that
of all the dams we investigated originally.
only the West Bijou Creek. .site "B." would be
justified under current criteria. and this is
assuming that Narrows is in operation.

During these studies we also looked at
the possibility of adding various systems
together. There is a figure 2 right after
page 28 in this packet. on some curves.
Assuming that West Bijou Creek dam was built.
we looked at the possibility of adding East
Bijou Creek dam. which was shown on plate 1.
and Agate dam. .using 3 1/4. 5 3/8 and 7 per-
cent interest rate. The analysis we have
gone through here indicates that if you draw
lines between some of these points here. that
you could add East Bijou Creek at 4 7/8 per-
cent and the combination of East Bijou and
Agate at 3 1/4 percent.

I

Our studies also have indicated the
potential diversion channel would be an
effective engineering solution to the problem
of flooding from Bijou Creek. We did not go
into enough detail in our studies on that
alternative to determine whether it is a better
alternative than the dams. for the simple
reason that there are some adverse effects

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