each of the action alternatives, and increased long-term road densities in the Beaver Creek and 

 Bear Creek drainage areas. 



Under Alternatives B and C the proposed restoration activities include installation of a headgate 

 structure at the irrigation ditch diversion of Beaver Creek and stabilization of the large gully 

 formed on an irrigation ditch with direct delivery into Bear Creek and Upper Willow Creek. 

 Other restoration activities include relocation and abandonment of several segments of road 

 which have unimproved ford crossings and are located in close proximity to streams and other 

 bodies of water. These measures are expected to result in a long-term reduction in sediment 

 delivery from existing and potential sources on school trust land. For example, the installation of 

 the headgate and erosion control / gully stabilization measures on the existing irrigation ditch are 

 expected to result in at least an 80 % reduction in the amount of annual sediment delivery to Bear 

 Creek. It is estimated that the gully currently contributes approximately 23 tons of sediment / 

 year directly into Bear Creek. 



Restoration work involved under Alternative D includes the relocation and abandonment of some 

 existing road segments. These measures are also expected to result in some long-term reductions 

 in sediment delivery from existing and potential sources on School Trust Lands, but not as much 

 as Alternatives B or C. 



Each of the proposed action alternatives would increase road densities in Bear Creek and Beaver 

 Creek watershed. However, the risk of additional sediment delivery from the proposed road 

 construction and temporary bridge crossings in Bear Creek and Beaver Creek are low. The 

 proposed roads are located on relatively gentle and stable side slopes. They are well buffered 

 from streams and ephemeral drainage features. All road drainage will be routed through 

 adequate filtration zones and not be directed to streams, stream crossings, or ephemeral drainage 

 features. No road construction is proposed within any SMZs except where necessary to cross a 

 stream. The proposed stream crossings of Bear Creek and Beaver Creek will utilize temporary 

 portable bridge structures. These structures have been designed with long spans that will not 

 require excavation or disturbance of the stream channel or stream bank. The crossing sites will 

 be stabilized and re-vegetated when the bridges are removed. 



Existing conditions for stream temperature and potential large woody debris recruitment would 

 be maintained under the proposed action. No timber harvests are proposed adjacent to streams or 

 with in the streamside management zones established on fish bearing streams within the project 

 area. Streamside management zone delineation would comply with requirements contained in 

 the Montana Streamside Management Law and Rules, and those contained in the State Forest 

 Land Management Plan. ImplementaUon of the SMZ Law and Rules, best management practices 

 and site specific recommendations of DNRC hydrologist and soil scientist will minimize the 

 potential for direct sediment delivery to streams from harvest areas and harvest acUvities. 



Predicted increases in average annual water yield and peak flows are low in Upper Willow Creek 

 and all of the other affected watershed analysis under each of the proposed action alternatives. 

 Incremental increases in water yield due to the State proposal would not be substantial and 

 cumulative increases would remain well below the established threshold levels. The risk of 



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