watervulnerability

Grand Mesa, Uncompahgre and Gunnison National Forest Watershed Vulnerability Assessment, Rocky
Mountain Region (R2)
Figure 7. Recreation Residences and Developed Sites in Riparian Areas
Initially, water use diversions and storage structures were going to be included as part of the infrastructure
value. These values were ultimately considered in the Water Use Values, below, where both the structures
and the amount of the associated water use (in acre feet for storage or cubic feet per second for flow) were
evaluated.
It is not enough to know which subwatersheds have the most infrastructure values. Two different
watersheds may have the same number of road and trail stream crossings, but there may be twice as many
miles of streams in one watershed than the other, which could potentially have much larger stream flows
and sediment/debris loads that could impact the crossings. Metrics used were designed to compare
subwatersheds in a more relative way. For each individual infrastructure value, the results were
standardized (results for each subwatershed were divided by the largest result of all the subwatersheds).
The standardized results for each infrastructure value were then summed to get a cumulative
infrastructure value (Stream Crossings + Roads and Trails in Riparian Areas + Recreation Developments
in Riparian Areas + Recreation Residences in Riparian Areas = Infrastructure Value Ranking). The
cumulative Infrastructure Value Rankings were classified into quartiles. The top 25% were classified 3
(high), middle 50% were classified 2 (moderate), lowest 25% were classified 1 (low). Figure 8 shows the
resulting Infrastructure Values Ranking.
73 Assessing the Vulnerability of Watersheds to Climate Change