watervulnerability

Recommendations

Info

Grand Mesa, Uncompahgre and Gunnison National Forest Watershed Vulnerability Assessment, Rocky Mountain Region (R2) Warmer fall, winter, and spring temperatures can result in more precipitation falling as rain instead of snow, particularly at elevations less than 8,200 feet. Most of the GMUG NF is above 8,200 feet in elevation, so the chance of rain-on-snow related flood events is judged to be relatively minor. (Only the Uncompahgre geographic area has significant area at elevations below 8,200 feet.) Periods of freezing weather will likely be shortened, especially on the Uncompahgre and Grand Mesa geographic areas, and road and trail surfaces at lower elevations can remain saturated and subject to rutting for longer periods. Warmer winter and spring temperatures will also result in earlier and more rapid snowmelt runoff, which can result in flooding and increased sediment/debris flows. Dust-on-snow events have already been documented to result in earlier and more rapid snowmelt runoff, with or without temperature increases (Painter et al. 2010). The greater risk to infrastructure values has to do with an increased severity in summer thunderstorm events. Increased summer temperatures are likely to increase the potential energy associated with convective storm development. These types of storms can result in very high-intensity rainfall events, capable of localized flooding, and in certain geomorphic settings (i.e., those subwatersheds with high risk for erosion or sediment production), triggering debris flows that are capable of great damage and risk to life. While high intensity summer storms could potentially occur anywhere on the Forest, they historically occur most frequently in the San Juans geographic area. Considering all this information, infrastructure values are most vulnerable in the San Juans and Upper Taylor geographic areas. Water Use Values Vulnerability Water use values are vulnerable to predicted climate change impacts in several ways. Structures related to water use values (dams, reservoirs, ponds, ditches, diversions) are most vulnerable to flooding and/or sediment and debris flows, similar to infrastructure values. Water Use Values related to Erosion Sensitivity × Activity Stressors are shown in Figure 28. The areas where erosion or sediment potential has the highest risk of affecting water use values structures are highest in the Upper Taylor, San Juans, and West Elk geographic areas. Because off-Forest water use data were not available for the Grand Mesa geographic area, some additional subwatersheds on the Battlement and Sunnyside areas could actually have higher risk rankings related to erosion sensitivity. Water Use Values related to Runoff Response Sensitivity × Activity Stressors are shown in Figure 29. The areas where runoff potential has the highest risk of affecting water-use-value-related structures are mostly in the San Juans geographic area, with smaller groupings of subwatersheds in the remaining geographic areas. Increasing peak flow and duration of high-stage events could result in storage and/or diversion facilities being overtopped or washed away. Timing of runoff may also come at periods where storage structures are full or are normally releasing water in preparation for later seasonal inputs. Increased sediment loads that could result from flooding may fill in storage structures and diversions, reducing the amount of water these facilities could hold or transport; this could potentially increase maintenance costs to dredge, replace, or repair affected structures. Geographic areas where water use related structures are most vulnerable are the San Juans and Upper Taylor. 102 Assessing the Vulnerability of Watersheds to Climate Change
Grand Mesa, Uncompahgre and Gunnison National Forest Watershed Vulnerability Assessment, Rocky Mountain Region (R2) Figure 28. Risk Ranking for Water Use Values related to Erosion Sensitivities and Stressors Figure 29. Risk Ranking for Water Use Values related to Runoff Response Sensitivities and Stressors 103 Assessing the Vulnerability of Watersheds to Climate Change
Page 2 and 3:
AUTHORS AND CONTRIBUTORS Authors* M
Page 4 and 5:
ASSESSSING THE VULNERABILITY OF WAT
Page 6 and 7:
staff; the task group included repr
Page 8 and 9:
Figure 2. Conceptual model for asse
Page 10 and 11:
Figure 3. Density of springs and sm
Page 12 and 13:
Using Historic Data One finding con
Page 14 and 15:
NF (Region 8) relied on information
Page 16 and 17:
level of uncertainty. Though there
Page 18 and 19:
climate (Casola et al. 2005). Only
Page 20 and 21:
sensitivity. Most were derived from
Page 22 and 23:
The sensitivity evaluation typicall
Page 24 and 25:
in exposure. The result of combinin
Page 26 and 27:
highest priority for management act
Page 28 and 29:
to information affected the assessm
Page 30 and 31:
with and rely on in many resource d
Page 32 and 33:
Pilot National Forest Reports Conte
Page 34 and 35:
Assessment of Watershed Vulnerabili
Page 36 and 37:
Gallatin National Forest Watershed
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47:
Page 48 and 49:
Page 50 and 51:
Page 52 and 53:
Helena National Forest Watershed Vu
Page 54 and 55:
Helena National Forest Watershed Vu
Page 56 and 57: Helena National Forest Watershed Vu
Page 68 and 69: Assessment of Watershed Vulnerabili
Page 70 and 71: Grand Mesa, Uncompahgre and Gunniso
Page 118 and 119: White River National Forest Watersh
Page 136 and 137: Coconino National Forest Watershed
Page 156 and 157:
Coconino National Forest Watershed
Page 158 and 159:
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Sawtooth National Forest Watershed
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Shasta Trinity National Forest Wate
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Umatilla National Forest Watershed
Page 218 and 219:
Page 220 and 221:
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
Ouachita National Forest Watershed
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Page 242 and 243:
Chequamegon-‐Nicolet National F
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
Page 258 and 259:
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
Page 272 and 273:
Chugach National Forest Watershed V
Page 274 and 275:
Page 276 and 277:
Page 278 and 279:
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
Page 294 and 295:
Page 296 and 297:
Page 298 and 299:
Page 300 and 301:
Page 302 and 303:
Page 304 and 305:
Page 306 and 307:
Page 308 and 309:
show all

watervulnerability

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?