WSP11018

• File Number: 8443.600
• Description: Narrows Unit - Studies
• State: CO
• Basin: South Platte
• Water Division: 1
• Date: 8/31/1964
• Author: Woodward-Clyde-Shera
• Title: Compritive cost Estimates for Earth Dams at the Lower Weld County and Narrows Alternative Damsites
• Water Supply Pro - Doc Type: Report/Study

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SCOPE

This report presents results of comparative cost estimates

for an earth dam at two alternative sites; (1) the Lower Weld
County site near Hardin, Colorado, and (2) the Narrows site near
Fort Morgan, Colorado. In our Report No. 7547-7354 dated March 11,
1964, covering engineering and geologic investigations at the Lower

Weld County site, our opinion was given that from the engineering

and geologic viewpoint, the Weld County site is superior to the

Narrows site, It was recommended that the Bureau make comparative

cost estimates of construction at these two sites. The U.S,B.R,

has completed the estimates for both sites, and we have reviewed
the design and estimates.

The basic conclusions resulting from our review are listed

briefly below followed by a discussion of criteria and assumptions
for the estimates made by our firm.

SUMMARY OF CONCLUSIONS

(1) The total yardage of compacted materials required for tbe
dam and foundation at the Narrows site is 7,400,000 cubic
yards while that required at the Lower Weld County site is
17,600,000 cubic yards, Both of these are based on the
assumption that the crest elevations presently planned and
furnished us are correct, i.e.; elevation 4610 for the
Lower Weld County site and elevation 4448 for the Narrows
site.

(2) In our opinion, the cost of the dam proper at the Lower Weld
County site will be approximately $11,000,000 higher (field
cost basis) than tbe dam at the Narrows site. The influence
of the dam cost on tbe cost of the overall project utilizing
U,S.B.R. figures and including U,S,B,R. indirect costs is
shown in Table I attached.

DISCUSSION

Data Furnished by U,S,B.R,
FollOWing is a list of U.S,B,R. data utilized for tbe estimates

made by our firm:

WOO[l'oVAfW,CtYO[_SlllR^"r; AND ^~!;OU^Tf5 __

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