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<br />CHAPTER 4. ENVIRONMENTAL CONSEQUENCES
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<br />(15.00 acres) which includes wetlands within Borrow Area A-I. Approximately 0.09 acres would
<br />be disturbed by the proposed powerline construction. Campground Relocation Sites 1 and 2 would
<br />not directly effect any wetlands. Inundation and filling are considered to be direct, long-term
<br />impacts resulting in the permanent loss of the wetlands affected.
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<br />It should be noted that the avoidance of wetlands was incorporated into the design of the Proposed
<br />Action. Utilization of an upstream, rather than a downstream raise would avoid the filling of
<br />additional wetlands on the downstream side of the dam.
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<br />As a pan of the proposed reservoir operation, discharges from the saddle dam through the Puppy
<br />Dog Lake spillway downstream would be reduced from higher historical levels to maximum
<br />discharges of approximately 20 cis. Concern exists for the fate and dependence on historical flows
<br />of the wetlands located around the lake and along the drainage downstream.
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<br />Puppy Dog Lake is a natural lake that is thought to have formed from natural drainage, and possibly
<br />spring seep, prior to the construction of Fish Creek Reservoir. Saddle dam seepage and the yearly
<br />high flows released into the lake following reservoir construction have affected the development of
<br />wetlands around the lake circumference. The degree to which this has occurred and extended the
<br />historical wetland boundaries, if at all, is unknown. As a part of the Proposed Action, the saddle
<br />dam to be constructed would also be designed to seep, though not to the degree that the existing
<br />dam seeps, and flows through the lake would be reduced. The effect this Proposed Action will have
<br />on wetlands existing around the lake is unknown at this time. It is known that Puppy Dog Lake,
<br />given its natural position, will remain following construction and ihat wetlands wi1\ surround the
<br />lake shore and be fed by saddle dam seepage and planned discharges. It is reasonably certain that
<br />the wetland acreage would not increase as a result of the Proposed Action. The wetland acreage
<br />could, therefore, remain constant due to the natural position and hydrology of the lake itself, or
<br />decrease somewhat due to the reduction in flows to be released through the reservoir during the
<br />early spring. It is most likely that any wetlands to be lost would be those of a more transitional
<br />nature (to upland conditions) and be located upslope from the lake shoreline.
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<br />With regard to the wellands downstream from Puppy Dog Lake, it is believed that lower flows
<br />would nor result in a loss of these wetlands. Higher historical flows were extremely brief in nature
<br />and are not thought to be the basis upon which these wetlands developed. It is assumed that these
<br />wetlands developed primarily as a result of subirrigation and flooding due to normal flows through
<br />the channel. Though it has not been quantified, lower flows should serve to support the existing
<br />wetlands through continuing natural creek overflow and subirrigation processes.
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<br />One positive indirect impact could occur to the wetland resource as a result of Alternative B.
<br />Though the basic effect of inundation is a loss of wetlands, some wetlands surrounding the proposed
<br />new high waterline, may naturally form as a result of inundation in the same manner as some of the
<br />existing wetlands formed. The potential for this to occur and the characteristics those wetlands
<br />would assume, cannot be accurately quantified at this point in time.
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<br />4.5.2.3 Altern.tive C. Sma liar Rasarvoir Expansion
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<br />A total of approximately 8.80 acres of wetlands would be affected under Alternative C as opposed
<br />to the 15.00 acres under Alternative B. The type and duration of this impact is considered to be the
<br />same as for Alternative B, with the exception that fewer wetland acres would be affected. Other
<br />impacts and the potential effectiveness of the proposed mitigation plan are the same for this
<br />alternative as for Alternative B, with one exception. With fewer impacted wetland acres to mitigate
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<br />S,!,,,mb<r 1993
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<br />Page 4.17
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