watervulnerability

Figure 3. Density of springs and small lakes on the Shasta-Trinity NFs. Results are shown for HUC-4 (left), HUC-5
(middle), and HUC-6 (right) scales. The Shasta-Trinity assessment evaluated resource value, sensitivity, and vulnerability
at the three scales, all showing that identifying priority locations for management actions was best done by
HUC-6.
The evaluation of water resources resulted in maps
and descriptions displaying the location and relative
importance by subwatersheds for each resource or
combination of resources. For example, the Shasta-
Trinity NF analyzed the density of springs and small
lakes at three watershed scales (Figure 3). The Sawtooth
NF displayed the relative importance of infrastructure
(road crossings and near-stream recreation facilities) by
subwatershed in the Sawtooth National Recreation Area
Figure 4. Amount of infrastructure (roads and developed
recreation facilities) within the Sawtooth NRA. Redshaded
subwatersheds have highest density of infra structure,
yellow show moderate density, and green show the
lowest density. Red lines are HUC-4 boundaries.
6 | ASSESSING THE VULNERABILITY OF WATERSHEDS TO CLIMATE CHANGE
Important Considerations in
Assessing Water Resources
• Identify partners who can improve the assessment
and engage with them.
• Identify the most important places (if possible),
categorize their relative values (high, moderate,
low), and map them.
• Determine what relevant broad-scale evaluations,
assessments, and plans are available.
• Consider all downstream uses (such as species and
diversions).
• Identify any ecological thresholds or risk levels
(flow requirements, temperatures, and so on)
associated with specific resource values.
• As the assessment progresses, look for similarities
(and differences) in response of resource values
and consider grouping resource values where
appropriate.
(Figure 4). The characterization of watersheds in terms
of the resources they support is an important step in any
watershed planning effort and a first step in informing
managers where limited resources might be invested.
The assessment goal was to identify the most important
places, categorize their relative value (high, moderate,
low), and map the individual and composite values.
Scale(s) of Analysis and Reporting