Amended Authorization for Great Western Reservoir, January 9, 1986

COLORADO WATER CONSERVATION BOARD Department of Natural Resources

721 State Centennial Building 131 3 Sherman Street Denver, Colorado 80203 Phone: (303) 866-3441

STATE

OF COLORADO

FROM: Bill McDonald

DATE: January 9, 1986

SUBJECT: Agenda Item 14a, January 16-17, 1986, Board

Meeting--Amended Authorization for Great Western Reservoir

The staff recommends that the Board recommend to the General Assembly that the previous authorization for the Great Western Dam and Reservoir, City of Broomfield, be amended to authorize

the larger project as set forth in the enclosed project summary.

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Enclosure: as stated

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Introduction

Colorado Water Conservation Board 721 State Centennial Building

1313 Sherman Street Denver, Colorado

January, 1986

Great Western Dam Project (City of Broomfield)

Draft 1/8/86

A loan in the amount of $2,156,000 was authorized for this

project under HB 1102 in the 1983 legislative session. Since

that time the city has re-evaluated the project and concluded that it should be expanded from the 9,100 acre-foot capacity recommended in 1983 to a 12,000 acre-foot capacity.

Problem

The City of Broomfield must enlarge the spillway of the

Great Western Dam to meet dam safety requirements. In addition,

the reservoir's storage capacity needs to be increased so that the city's current water rights can be developed to meet the

increasing demands of its water users. The increased water

demands are due to the 3 percent growth per year that the city is currently experiencing.

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Project Study

Subsequent to the Board action taken on this proposed

project in 1983, the City of Broomfield fully funded an amended feasibility study which was prepared by Rocky Mountain

Consultants, Inc. That amended study is the basis for the

recommendation on this project.

Proposed Project

The amended study determined that the City of Broomfield should construct a new spillway at the Great Western Dam which would pass the probable maximum flood and enlarge the reservoir

to a capacity of 12,000 acre-feet. Such an enlargement would

require raising the existing dam embankment by 34 feet. It is

anticipated that these improvements will satisfy Broomfield's raw water storage requirements until about the year 2015.

Proposed Financing

The total estimated cost of the project is now $9,200,000. This includes $1,281,000 for the aquisition of 414 acres of land

for right-of-way around the reservoir. The proposed financing

for the project is as follows: City of Broomfield funds

CWCB loan (already authorized by HB 1102)

Additional CWCB loan

(to be repaid by user charges)

Total -2-$4,600,000 $2,156,000 $2,444,000 $9,200,000

Under this financing arrangement Broomfield would have to repay the CWCB, at five percent interest, $268,088 per year for 40 years for a total of $10,723,520.

Recommendation

The Board recommends that the General Assembly amend the authorization for the project subject to the terms of the proposed financing specified above.

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