Ephemeral draws and other drainage features that lack discemable stream channels or are 

 discontinuous drain most of the proposed harvest area. Selection of appropriate operating 

 seasons, limiting equipment operations to suitable slopes or designated trails and appropriate 

 ground conditions, and implementation of appropriate BMPs and mitigation measures will 

 be used to reduce the risk and severity of soil erosion and potential sediment delivery to 

 streams and ephemeral drainage features. 



Action Alternatives B and C include plans for watershed restoration activities. These 

 watershed restoration measures include: 1) Installation of a headgate structure at the existing 

 Beaver Creek irrigation diversion, 2) stabilization of headcut and extensive gully erosion on 

 existing irrigation ditch, 3) improvements designed to reduce erosion on existing roads, 4) 

 relocation of several segments of poorly located existing road, and 5) abandonment and 

 reclamation of several segments of existing roads. 



There are some moderate risk of short-term increases in sediment delivery to Beaver Creek, 

 Bear Creek and Upper Willow Creek during and/or shortly after the installation of the 

 proposed headgate structure and gully stabilization measures on the existing irrigation ditch. 

 However, application of BMPs, site-specific design and mitigation measures are expected to 

 reduce erosion and potential sediment delivery to an acceptable level as defined under the 

 Montana Water Quality Standards. Acceptable levels are defined as those conditions 

 occurring where all reasonable land, soil, and water conservation practices have been 

 applied. These restoration activities are expected to reduce long-term erosion and sediment 

 delivery to Beaver Creek, Bear Creek and Upper Willow Creek. 



The risk of water quality impacts that are associated with the proposed new road 

 construction, temporary stream crossings, permanent culvert installations and timber harvest 

 units are low. All of the proposed action alternatives include watershed and fisheries 

 restoration measures that are designed to reduce sediment delivery to streams and ephemeral 

 drainage features. The overall long-term effects of implementation of any of the proposed 

 action alternatives would be improved water quality, improved protection of cold water 

 fisheries and other downstream beneficial uses when compared to the current existing 

 conditions. Action Alternative D also contains similar restoration activities proposed in 

 Action Alternatives B and C. Although, in this alternative the gully erosion on an existing 

 irrigation ditch will not be repaired due to economic concerns. This site of gully erosion has 

 been identified as a significant source of sediment to Bear Creek. It is likely that the gully 

 erosion will continue to be a long-term impact to water quality if no restoration activities are 

 done to remedy this problem. 



Risk of both short-term and long-term impacts to water quality are greatest under the no action 

 alternative and Alternative D if we are unable to fix the ditch. This is due to the fact that 

 watershed improvement projects designed to rehabilitate or mitigate existing sources of sediment 

 would not be implemented under the no action alternative or Alternative D. Watershed 

 rehabilitation measures would not be implemented because there would be no project or revenue 

 to fund the proposed improvements. Of primary concern is the continued erosion and expansion 

 of the large irrigation ditch gully. This gully has been identified as the single largest existing 



78 



