Sorting for priority 

  A. Introduction

  1. What streams have the largest habitat volume, greatest resilience to dewatering, and most habitat length?

  2. Those characteristics could be a basis for good choices in efforts to protect and preserve trout habitat.​

  3. Results of sorting using combined and individual characteristics are shown and described below.

Protections | Priority | Comparison | Tool

 

1. Sorting candidate streams using combined characteristics

Sort18.jpg

2. Sorting candidate streams based on characteristics individually

SortInd.jpg

  B. Candidate streams

  1. Protections underway already at 22 streams include Outstanding Waters and Instream Flow Program protection.

  2. Are all 22 streams good candidates for prioritization?

  3. Fish and Stoner have active surface water diversions for agriculture.

  4. Consequently, their stream flows are reduced during warm weather, increasing habitat stress.

  5. That is, they are not good candidates to consider further for habitat preservation resources.

  6. Taylor temporarily dewatered to dryness in 2019, so it is not a good candidate, either.

  7. Rough canyon is a tributary of Roaring Forks, so there is no reason to consider it separately.

  8. This leaves 18 of the 22 streams as candidates for proceeding with an approach to prioritization.

  C. Sorting the candidates​

a. Background

  1. Flow can be used to represent habitat volume.

  2. Resilience would be evident from flow amounts during summertime conditions and year around.

  3. Flow was found to correlate with stream drainage area and maximum elevation.

  4. Logically, larger drainage area would collect more precipitation for generating stream flow.

  5. And higher elevations would mean more snowmelt to contribute to the recharge of stream baseflow.

  6. See sorting with stream characteristics.

  7. Including stream length produced the next best correlation.

  8. Stream characteristics for the correlation assessments were from application of StreamStats.

b. Sorting​

  1. Table 1 above shows the 18 candidate streams sorted by those characteristics identified in table 2.

  2. Scores are proportional, based on comparison with the highest value for each characteristic.

  3. Individual scores were summed for total scores.

  4. That is, for example, Bear has the highest July-August mean flow, 49.55 cfs, and obtains a score of 100.

  5. East Fork has a July-August mean flow of 35.70 cfs, which is 72 percent of 49.55 cfs.

  6. The sum of proportional scores for Bear is 493, shown in the table, so its overall score is 100.

  7. Bear is at the top of the sorting of candidates, based on the characteristics used.

  8. East Fork has 68 percent of Bear’s score and is second in the sorting.

  9. For comparison, table 2 shows results with the same stream characteristics applied individually.

  10. There is both similarity and variation within the table 2 listings.

  11. For example, Bear and Roaring Forks are high in 4 of the 5 sorts.

  12. Kilpacker is at the bottom, at the top, and roughly in the middle in 4 of the sorts.

Protections | Priority | Comparison | Tool