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..,. ?..r,.,,? ., . .. ?.,.,..... ?. ? . ,........ ?,., ?. ..? ?.. ....., ?.??...y..?.? the number of acres harvested or volume. Variations in silvicultural prescriptions, harvest
<br />methods, quality of project implementation, species composition, aspect and elevation and
<br />precipitation (where the harvests are proposed) affect the levels of water yield increases.
<br />Poor road location and inadequate or excessive stream crossings can also impact the fluvial
<br />system. Surface runoff from roads directly into the stream channels increases the amount of
<br />sediment in the stream. Improper culvert size or placement also increases sediment production.
<br />These are adverse effects to the fluvial system if the amount of sediment is too high for the
<br />stream channel's capacity. Although there are instances of this condition on the Forest, they are
<br />not widespread and are not adversely affecting the fluvial system to a significant level.
<br />Potential adverse effects as a result of road construction and reconstruction is not exclusively
<br />dependent on miles or acres of land disturbance. Using an erosional index method, which takes
<br />into account the inherent erodibility of soils, potential impacts are analyzed. At this level of
<br />planning, it is not possible to determine the location of roads within a watershed. Thus,
<br />connected disturbed area analysis associated with road construction can not be completed.
<br />Only the acres of watershed disturbance due to roads can by analyzed. Altemative E has the
<br />highest risk of adverse effects followed in order of risk by Altematives A, G, D, C, B and F.
<br />Similar to timber harvesting, roads potentially could have an impact to the riparian/wetlands
<br />areas. Location of the road within the riparian zone is the primary concem. Inappropriate width
<br />filter strips or improper drainage between the road and stream ean produce additional sediment
<br />loading. Sidecast construction or improper road maintenance of existing roads can result in
<br />damage to riparian vegetation as well as increasing stream sediment loads. The effects of the
<br />alternatives were based on the acres of watershed disturbed. The ranking of altematives are the
<br />same as in the above paragraph.
<br />Spatial distribution of timber harvest is important. The number of watersheds entered and acres
<br />harvested by watershed indicate potential effects on watershed health. This analysis looks at
<br />levels of harvest within each watershed and rates risk based on this factor. If not used, effects of
<br />two alternatives with similar volumes, but one entering fewer watersheds for the ASQ, would be
<br />similar. By spreading out water yield increases over more watersheds, potential adverse effects
<br />are also spread out. Using the number of acres harvested by watershed, potential effects of
<br />implementing Altemative E and A would be of highest risk followed in order by Alternatives G, D,
<br />C, B and F. .
<br />Soil and water improvements are positive effects of timber management in this analysis. These
<br />projects reduce existing levels of connected disturbed areas, and other chronic sources of
<br />sediment in streams that affect aquatic and overall watershed health. In this analysis, projected
<br />soil and water improvements are measured in acres. Implementation of Alternative A would
<br />result in the highest level of improvements followed in order by Altematives E, G, D, C, F and B.
<br />To determine potential effects of implementation of any of the alternatives on the water
<br />resource, all timber management activities; acres harvested, water yield increase due to
<br />harvest, roads constructed and reconstructed, erosion index for soils, number of watersheds
<br />entered, and soil and water improvements, must be considered. Taking all of these factors into
<br />account, implementation of Altemative A has the highest risk for potential adverse effects to the
<br />water and riparian resources followed in order by Alternatives E, G, D, C, B, and Altemative F
<br />shows the least risk of adverse effects to water and riparian resources.
<br />Alternatives A, E and G are very similar in volume produced, acres harvested, roads constructed
<br />and reconstructed, and acres of soil and water improvements accomplished. Differences
<br />Routt Nationa/ Forest - E/S (Water/RJparlan/Wetlands) 3-47
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