EVALUATION PROCESS 

 Approach 



This study will be conducted with three end products in mind: (a) a map showing 

 the location of identified natural features; (b) a tabular summary of the features 

 identified, by river basin; and (c) documentation of the value classes assigned to 

 each feature. Unlike some of the other resource inventories conducted as part of the 

 Montana Rivers Study (e.g., fisheries), this study will not rely initially on the 

 designation of river reaches or segments. Individual sites will be plotted on the map 

 and assigned to a value class, so that the occurrence of sites within any arbitrarily 

 designated river reach or segment can be determined. Near the end of the study, river 

 segments may be assigned to value classes based on the number and value class ratings 

 of the natural features they contain. 



The study will rely on existing data and expertise within the cooperating agencies 

 to the greatest extent possible. Existing data bases will be searched before any 

 field inspections are made. Field inspection will be limited to sites or areas which 

 are believed to have outstanding value natural features which have not been adequately 

 studied. 



Inventory effort will concentrate on sites meeting the criteria for value classes 

 1 and 2. An effort will be made to catalogue 90-100% of these features of statewide 

 or national importance. The study will probably identify only 10-40% of the value 

 class 3 and 4 features. 



An advisory committee has been assembled to guide the study. Members and 

 affiliations are listed in Appendix A. 



As the study progresses, an attempt will be made to refine the criteria and 

 standards. For example, it may be possible to specify a height to width ratio for 

 gorges allowing objective assignment to a value class based on measurements. 



Limitations 



While every effort will be made to identify all or nearly all Montana natural 

 features of value classes 1 and 2, it should be emphasized that this is a preliminary 

 and low-intensity reconnaissance rather than an exhaustive inventory. River reaches 

 in which no high-value natural features are identified during this study may be found 

 during more detailed study to contain much of value. 



Mapping and Tabulation Methods 



As sites are located, they will be plotted on a set of 1:100,000 USGS topographic 

 maps using colored signal dots: green for botanical resources, and red for geological 

 or hydrological features. Each site will be given a unique number which will be 

 lettered on the appropriate signal dot. Numbers will correspond to an information 

 sheet that will be completed for each site (see Appendix B). 



Dams and reservoirs will be plotted on a separate 1:1,000,000 map of Montana in 

 order to allow determination of free-flowing reaches. All drainage area in the state 

 upstream from a major impoundment will be indicated on the map. 



A reliability diagram, showing the relative intensity of study effort and 

 reliability of data, will accompany the inventory map. 



