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Chequamegon-­‐Nicolet National Forest Watershed Vulnerability Assessment, Eastern Region (R9)<br />

geochemical cycling. These results were extrapolated to all HUC-6s on the Forest based on their<br />

percentage of total and acid wetland, and each watershed was placed into one of four classes representing<br />

its vulnerability to climate change impacts on wetlands.<br />

Groundwater Recharge<br />

Results from soil water balance modeling for the Park Falls unit of the Chequamegon-Nicolet NF, using<br />

WICCI downscaled data for one location, just one GCM (GFDL-CM2.0), and one scenario (A1B),<br />

indicates potential groundwater recharge may increase about 7 percent in the future. While these are<br />

preliminary results, they indicate that groundwater recharge might be somewhat resilient to climate<br />

change impacts.<br />

Potential groundwater recharge and increases in recharge were related to hydrologic soil group with<br />

coarse textured soils having the highest potential average recharge (13.5 in/yr) and increase in recharge<br />

(1.4 in) and fine textured or peat soils having the least potential average recharge (3.5 in/yr) and increase<br />

in recharge (0.0 in).<br />

These results were extrapolated to all HUC-6s on the Forest and each watershed was placed into one of<br />

four classes representing its vulnerability or resilience to climate change impacts on potential<br />

groundwater recharge.<br />

Infrastructure-Culverts<br />

The WICCI downscaled climate projections provide sufficient scientific evidence that the frequency and<br />

intensity of large precipitation events will increase and will likely increase floods. Indices of road-stream<br />

crossing density and runoff potential based on HSG were developed and used to classify the vulnerability<br />

of HUC-6s to impacts on infrastructure. The most vulnerable watersheds have high runoff potential and<br />

high stream crossing densities. For watersheds with low to moderate runoff potential, sizing stream<br />

crossing structures to channel bankfull width is an adaptive strategy that will most likely accommodate<br />

future increases in flood flows. And while hydrologic and hydraulic modeling should be conducted for all<br />

stream crossing designs, it is especially important for watersheds with very high runoff potential. In those<br />

cases, hydraulic modeling should be conducted to ensure structures pass the 100-yr flood, and preferably<br />

the 500-yr flood, with the HW/D

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