watervulnerability

Chequamegon-­‐Nicolet National Forest Watershed Vulnerability Assessment, Eastern Region (R9)
GW Recharge Difference (inches/yr)
1.5
1.25
1
0.75
0.5
0.25
0
-­‐0.25
A B C D Water
Hydrologic Soil Group
Figure 13. Average annual difference in potential groundwater recharge by hydrologic soil group
These estimates need to be viewed cautiously; but in spite of these shortcomings, the regressions are
strong, they are consistent with the modeled results by HSG, and the climatic differences across the Forest
are not large. Therefore, they should provide reasonable estimates for the entire Forest until more
comprehensive modeling can be conducted.
The number, location, and relative vulnerability of the four HUC-6 classes are presented in Figure 14.
The groundwater recharge watersheds have few or no streams, very high permeability, and are entirely
groundwater recharge zones that were considered to be resilient or to have very low vulnerability to
impacts from the projected climate change. There were 12 watersheds in this class; nine were split HUC-
6s and three were complete HUC-6s. All were located on the Bayfield Peninsula. The estimated average
annual future and historic potential groundwater recharge for these watersheds were 13.4 and 12.4 inches,
respectively, resulting in an average increase of 1.0 inch (Table 4). These watersheds may provide the
best opportunities on the Forest to implement adaptive management practices to respond to climate
change for resources other than water.
HUC-6 # of Est. Avg. Annual Potential
Watershed HUC-6 Groundwater Recharge (inches)
Class Watersheds 2046-2065 1971-1990 Difference
Groundwater Recharge 12 13.4 12.4 1.0
Groundwater Runoff 50 10.1 9.4 0.7
Mixed Runoff 59 8.6 8.1 0.6
Surface Runoff 37 7.0 6.6 0.4
Table 4. Estimated Average Potential Groundwater Recharge for the historic (1971-1990)
and future (2046-2065) time periods for HUC-6 watersheds on the Chequamegon-Nicolet NF
251 Assessing the Vulnerability of Watersheds to Climate Change