C150240 Vegitation Montioring Analysis

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I I FUNCTIONAL ASSESSMENT I The Grand Mesa Wetland Function and Value Assessment, or "Grand Mesa Method" (GMM), was used to assess the functional attributes of wetlands that have reestablished in the interim of I fill restrictions imposed on the dam. The GMM is a wetland assessment method specifically designed to assess function and value of wetlands on the Grand Mesa between the elevations of 9,000 and 11,000 feet (WestWater 2009). IThe GMM acknowledges that some types of wetlands have a higher relative importance associated with the functions that they perform. The functions performed by the complexity of a I riverine system or fen wetland are greater than other types of wetlands. Multipliers are used for these systems to reflect this increased function. Because the GMM uses multipliers for riverine and fen communities, a GMM assessment was completed for wetlands/fens found in the newly I inundated zone between the restricted water level elevation (9,857.5 ft) and the high water level elevation(9,864 ft). I Seven indices are used to determine the total weighted index value. Each index is weighted based on its relative importance. Hydrogeomorphology and vegetation carry the highest weight factors. The index value is multiplied by its weight factor and summed to determine the total weighted I index value. To determine the total wetland value the summed weighted index value is multiplied by the number of acres. The total wetland value is used to help identify potential restoration or enhancement opportunities. Completed GMM forms for each analysis year are included in the I accompanying compact disc. Indices used to assess function are listed below. • Hydrogeomorphology Condition Index • Vegetation Index I • Water Quality Index • Wildlife Habitat Index • Threatened, Endangered, and Sensitive Species (TESS) Index I • Recreation Index • Buffer Condition Index I The purpose of the 2010 functional assessment was to establish baseline data for existing conditions for the wetland within the newly inundated zone prior to inundation. As the reservoir was filled and drawn down in subsequent monitoring years the GMM documented functional Ichanges in wetlands as a result of periodic inundation. Methods IMichael Klish (Principal Environmental Scientist, WestWater Engineering), Brett Fletcher (Environmental Scientist/Wetland Biologist, WestWater Engineering), and Michael Villa, Ph.D. I (Environmental Scientist/Wetland Biologist, WestWater Engineering) completed the GMM in 2010. Their scores were averaged and will serve as the baseline functional value for 2010. I Since Lonnie Renner (Environmental Scientist/Biologist, WestWater Engineering) was present and completed GMM assessments in 2011, 2012, and 2014, only his values would be used for those years (previous annual reports averaged the GMM scores of multiple biologists). IWestWater Engineering Page 8 of 14 February 2015