C153773 Feasibility Study

• Contract/PO #: C153773
• Contractor Name: Morrison, Town of
• Contract Type: Loan
• Water District: 9
• County: Jefferson
• Bill Number: HB 95-1155
• Loan Projects - Doc Type: Feasibility Study

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

Plan 0-1

This plan assumed upgrading (replacement) of the existing gravity system.

Plan 0-2

This plan provided for a new diversion dam (located just north of the treatment
plant), sand trap, raw water pumping station, and pipelines.

Plan 0-3 and Plan 0-4

These plans involved two new diversion locations, with raw water
pumps, similar in concept to Plan 0-2, except using different dam
locations.

WRC concluded that Plan 0-2 was preferable to 0-1 and either 0-3 or 0-4. This conclusion was
questioned by the Town of Morrison; and a reevaluation specifically required as part of the current
Master Plan effort.

A detailed comparative evaluation of two plans was undertaken and included in the MWE 1996
Master Plan. Please refer to Section III, pages 5 through 15 of the appended Report. Option B-2
in the Master Plan is essentially the same as 0-2, The probable initial capital investment for the
gravity flow plan (Option B-1) was shown to be less than for B-2, Further, the comparative annual
costs for Option B-1 was shown to be less for two size levels, as shown in Table III-C ofthe Master
Plan. ($47,400/yr for B-1 at the lower load level versus $64,250/yr for B-2 - or 35% higher costs
for Option B-2.) The following table summarizes cost comparisons for the two plans.

Comoarative Caoital Cost
Without dam replacement
Assuming dam replacement

Option B-1
$360,000
$510,000

Option B-2
$545,000
$515,000

Comoarative Annual Cost
1000 EQR level

$47,400

$68,950

The principle reason for the difference of opinion is the assessment of the usability of the 12-
inch cast iron pipe transmission line. WRC assumed that the entire line (stated to be 4,300
linear feet) would have to be replaced, at a total estimated cost of approximately $320,000, In
actuality, the problems and concerns regarding the transmission line are primarily with the much
older, upper 800-foot segment which had not been replaced in 1961 - and with the masonry
settling basins. Field checks and research by MWE indicated that the 12-inch cast iron pipe portion
is still in relatively good useable condition - and need not be replaced in the foreseeable future,
If the cost of replacing this line is deducted from the WRC estimate, then using WRC estimates,
Alternative 0-1 (Le" Option B-1) results in lower capital cost. With anticipated reasonable

70-080.039P:REPORT

II-3