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<br />CHAPTER 4. ENVIRONMENTAL CONSEQUENCES
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<br />Operation Plan - The primary design goal for the proposed operation plan for Alternative B is to
<br />minimize potential erosional impacts to and degradation of the Puppy Dog Lake drainage. An
<br />additional goal of the proposed plan is to provide for the main1enance of in-stream flows.
<br />lmplementation of this operating plan would utilize the additional outlet capacity of the proposed
<br />reservoir, the capability to operate the outlet structures remotely, and the ability to remotely
<br />monitor reservoir level and influent flows.
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<br />The capacity of the outlet structures in the proposed dam enlargement would increase from
<br />approximately 60 cfs to approximately 200 cfs. By aIlowing larger volumes of spring runoff to be
<br />released to the Middle Fork of Fish Creek, flows over the spillway would be minimized during
<br />spring runoff.
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<br />The remote telemetry system would monitor inflows from the Upper Middle Fork of Fish Creek
<br />and Granite Creek, the release rate of reservoir flows to the Middle Fork of Fish Creek through the
<br />outlet structures, and the reservoir level. The release rate could be remotely adjusted to allow
<br />complete filling of the reservoir to occur in late June, or early July, rather than early June.
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<br />Once the reservoir is filled, the outlet would be adjusted as necessary to ensure that spillway flows
<br />would not exceed 20 cfs. The operation plan could be modified if the maximum proposed spillway
<br />flow of 20 cfs was found to be inadequate for erosion protection in the Puppy Dog Lake drainage
<br />(Birch, 1992a). This would be determined through monitoring effom.
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<br />Water Rights - As described in Section 3.3, Water Resources, twO conditional water rights were filed
<br />by the City in anticipation of enlargement of the Fish Creek Reservoir. The first conditional storage
<br />right obtained in 1980 was for 2,000 AF. The second conditional storage right was filed in August
<br />1992 for 200 AF. The Colorado Water Conservation Board (CWCB) objected to this filing on the
<br />basis that the Applicant's proposed reservoir expansion would inundate existing, minimum stream
<br />flow rights on the Upper Middle Fork of Fish Creek, and Granite Creek that are senior to the
<br />additional 200 AF. In a stipulation agreement between the City and the CWCB, CWCB recognizes
<br />that the City intends to release water from the 200 AF enlargement in order to maintain in-stream
<br />flows in downstream sections of Fish Creek, and that the City would develop a Donation
<br />Agreement. This agreement requires that the City construct habitat improvement structures in
<br />lower Fish Creek. The stipulation was formally adopted by both parties on December 31, 1992 and
<br />is presented in Appendix G.
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<br />Water Demand/Reservoir Storal!:e Reauirements - Under this Alternative, a total reservoir storage
<br />capacity of 4,518 AF would be available as shown in Table 4-2. With the implementation of
<br />Alternative B, both the City and Mt. Werner would have sufficient water supply to meet present
<br />and projected 20-year water demands. Effective conservation measures and/or the utilization of the
<br />infiltration galleries or fisheries pool during low flow/peak demand periods would be required,
<br />however, to meet long-term 40-year demands projections. This would be the case whether or not
<br />the twO entities would choose to consolidate. Under this alternative, approximately 1,030 AF of
<br />storage capacity would be available as a fisheries pool during most years.
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<br />Water Oualitv - With the implementation of Alternative B, the community would continue to
<br />receive high quality water from the Fish Creek basin. The development of additional water supplies
<br />would not. be necessary.
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<br />Sepumber 1993
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<br />Poge 4.9
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