Environmental Impact Statement - Sonoma Land Trust

More documents

Recommendations

Info

California Department of Fish and Game U.S. Fish and Wildlife Service Section 3.2. Surface-Water Hydrology, Tidal Hydraulics, and Sedimentation patterns. Therefore, this impact is considered less than significant, and no mitigation is required. Conclusion: Less than Significant. Impact HYD-6: Modification to Tolay Creek Morphology and Sedimentation Processes Proposed Project According to the Hydrodynamic Model, the tidal range within Tolay Creek is currently muted, meaning the full tidal prism cannot be achieved due to the channel mouth being undersized. It is estimated that the existing tidal range in the Upper Lagoon adjacent to the northeast portion of the Project is muted by 43 to 57%, midway up Tolay Creek by 16%, and 10% by the mouth of Tolay Creek (Moffatt and Nichol 2011). Breach 1 would not affect Tolay Creek morphology and sedimentation processes because it reconnects the site to San Pablo Bay. Breach 2 would result in slightly increased tidal damping and potentially reduced sedimentation in the Upper Lagoon in Tolay Creek as tidal waters flow into the Sears Point restoration site instead of proceeding upstream in Tolay Creek. The breaches and Tolay Creek itself would likely erode after levee breaching and tidal prism would increase gradually as the tidal range is captured over time. This process would continue as sediment accumulates within the restored area, and would eventually reach equilibrium with the new tidal prism. The increase in tidal velocities due to the higher flows in Tolay Creek following construction of any combination of Breaches 2 – 4 would likely increase the scouring at the mouth of Tolay Creek and reduce the time to reach full tidal equilibrium. For Breaches 2-4, there would be localized changes in Tolay Creek morphology and sedimentation processes during establishment of the wetlands restoration site. The potential effect of Breach 2 would be limited, and no mitigation is required. If Breaches 3 or 4 are required due to the need for adaptive management of the project area, then there is the potential for an impact to Tolay Creek. It is difficult to assess the level of impact given that the Creek is likely still responding to the Tolay Creek Restoration Project, and that it may be many years before additional breaches would be required (if ever), and that there are limited monitoring data for the Creek. The adaptive management evaluation that would lead to the decision to construct either or both of Breaches 3 – 4 would also take into consideration potential effects on Tolay Creek including any measures needed to reduce damping in the Creek. Measures to address the potential tidal dampening effect of Breaches 3 and 4 would be incorporated into the design of these breaches, and the potential effect of Breaches 3 and 4 would therefore also be less than significant. Conclusion: Less than Significant Sears Point Wetland and Watershed Restoration Project Final Environmental Impact Report/Environmental Impact Statement 3.2-18 April 2012
California Department of Fish and Game U.S. Fish and Wildlife Service Section 3.2. Surface-Water Hydrology, Tidal Hydraulics, and Sedimentation Full-Tidal Alternative There would be localized changes in Tolay Creek morphology and sedimentation processes during establishment of the wetlands restoration site similar to that of the Project. With a substantially larger area proposed for the new tidal basin and no dredging of Tolay Creek, potential impacts on tidal muting and associated reduction in sedimentation in Tolay Creek restoration area would be greater than in the Project and would likely result in muting greater than under existing conditions. This impact is considered significant but could be mitigated through Mitigation Measure HYD-MM-2. Mitigation Measure HYD-MM-1: Avoid Unacceptable Levels of Tidal Muting in Tolay Creek If the Full Tidal Alternative is selected, , and a decision is made to implement any portion of Breaches 3 and 4 during the adaptive management phase of the restoration, SLT shall further evaluate the need for specific actions to avoid unacceptable muting in Tolay Creek. SLT shall first consult with USFWS to determine an acceptable level of tidal muting. If modeling or monitoring data indicate that the proposed adaptive management breaches could lead to an unacceptable level of tidal muting, SLT shall evaluate measures such as phased breaches, smaller breaches, deepening of Tolay Creek, and other potential measures that would reduce tidal muting. The final determination regarding the appropriate combination of breaches and measures to mitigate potential muting in Tolay Creek shall be determined in consultation with USFWS, CDFG, CalTrans, and other appropriate agencies. Conclusion: Less than Significant with mitigation. Impact HYD-7: Modification to San Pablo Bay Morphology and Sedimentation Processes Proposed Project The capture of sediment in the restoration area is unlikely to result in lower local sediment concentrations in San Pablo Bay, because the deposition in the restored tidal wetlands will be only a small fraction of the suspended sediment that enters the wetlands during each tidal cycle. The amount of sediment required to sustain maximum accretion rates for a nearby wetlands restoration site was only a small fraction of the total estimated sediment inflow into San Pablo Bay from the Sacramento and San Joaquin Rivers (Jones & Stokes 2003). Therefore, the impact of the Project on overall San Pablo Bay sedimentation processes is considered to be less than significant, and no mitigation is required. Conclusion: Less than Significant. Sears Point Wetland and Watershed Restoration Project Final Environmental Impact Report/Environmental Impact Statement 3.2-19 April 2012
Page 1 and 2:
Sears Point Wetland and Watershed R
Page 3 and 4:
Sears Point Wetland and Watershed R
Page 5 and 6:
Contents List of Tables ...........
Page 7 and 8:
California Department of Fish and G
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Executive Summary This summary prov
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Table ES-1. Summary of Impacts and
Page 33 and 34:
Table ES-1. Continued Page 3 of 141
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Table 1-1. List of Local, State, an
Page 53 and 54:
Table 1-1. Continued Page 3 of 3 Ag
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Table 2-2. Action Alternatives Cons
Page 71 and 72:
Table 2-2. Continued Page 3 of 4 Ut
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110: California Department of Fish and G
Page 119 and 120: Chapter 3 Affected Environment and
Page 121 and 122: Section 3.1 Geology, Soils, and Pal
Page 143 and 144: Section 3.2 Surface-Water Hydrology
Page 159: California Department of Fish and G
Page 165 and 166: Section 3.3 Water Quality Introduct
Page 193 and 194: Section 3.4 Public Health and Safet
Page 211 and 212:
Page 213 and 214:
Page 215 and 216:
Page 217 and 218:
Page 219 and 220:
Page 221 and 222:
Page 223 and 224:
Table 3.5-2. Special-Status Species
Page 225 and 226:
Table 3.5-2. Continued Page 3 of 12
Page 227 and 228:
Page 229 and 230:
Page 231 and 232:
Page 233 and 234:
Page 235 and 236:
Page 237 and 238:
Page 239 and 240:
Page 241 and 242:
Page 243 and 244:
Page 245 and 246:
Page 247 and 248:
Page 249 and 250:
Page 251 and 252:
Page 253 and 254:
Page 255 and 256:
Page 257 and 258:
Page 259 and 260:
Page 261 and 262:
Page 263 and 264:
Page 265 and 266:
Page 267 and 268:
Page 269 and 270:
Page 271 and 272:
Page 273 and 274:
Section 3.6 Land Use and Public Uti
Page 275 and 276:
Page 277 and 278:
Page 279 and 280:
Page 281 and 282:
Page 283 and 284:
Page 285 and 286:
Page 287 and 288:
Page 289 and 290:
Section 3.7 Agricultural Resources
Page 291 and 292:
Page 293 and 294:
Page 295 and 296:
Page 297 and 298:
Page 299 and 300:
Page 301 and 302:
Page 303 and 304:
Page 305 and 306:
Page 307 and 308:
Page 309 and 310:
Page 311 and 312:
Page 313 and 314:
Page 315 and 316:
Page 317 and 318:
Page 319 and 320:
Page 321 and 322:
Page 323 and 324:
Page 325 and 326:
Page 327 and 328:
Page 329 and 330:
Page 331 and 332:
Page 333 and 334:
Page 335 and 336:
Page 337 and 338:
Page 339 and 340:
Page 341 and 342:
Page 343 and 344:
Page 345 and 346:
Page 347 and 348:
Section 3.11 Air Quality Introducti
Page 349 and 350:
Table 3.11-1. Ambient Air Quality S
Page 351 and 352:
Page 353 and 354:
Page 355 and 356:
Page 357 and 358:
Table 3.11-32, Continued Page 2 of
Page 359 and 360:
Page 361 and 362:
Page 363 and 364:
Page 365 and 366:
Page 367 and 368:
Page 369 and 370:
Page 371 and 372:
Page 373 and 374:
Page 375 and 376:
Page 377 and 378:
Section 3.12 Noise Introduction Thi
Page 379 and 380:
Page 381 and 382:
Page 383 and 384:
Page 385 and 386:
Page 387 and 388:
Section 3.13 Cultural Resources Int
Page 389 and 390:
Page 391 and 392:
Page 393 and 394:
Page 395 and 396:
Page 397 and 398:
Page 399 and 400:
Page 401 and 402:
Page 403 and 404:
Page 405 and 406:
Section 3.14 Aesthetics Introductio
Page 407 and 408:
Page 409 and 410:
Page 411 and 412:
Page 413 and 414:
Page 415 and 416:
Section 3.15 Environmental Justice
Page 417 and 418:
Page 419 and 420:
Page 421 and 422:
Page 423 and 424:
Chapter 4 Consultation and Other Re
Page 425 and 426:
Sonoma Land Trust Chapter 4. Consul
Page 427 and 428:
Page 429 and 430:
Page 431 and 432:
Page 433 and 434:
Page 435 and 436:
Page 437 and 438:
Page 439 and 440:
Page 441 and 442:
Page 443 and 444:
Chapter 5 Public Involvement and Sc
Page 445 and 446:
Page 447 and 448:
Page 449 and 450:
Page 451 and 452:
Page 453 and 454:
Sonoma Land Trust Chapter 7. Refere
Page 455 and 456:
Page 457 and 458:
Page 459 and 460:
Page 461 and 462:
Page 463 and 464:
Page 465 and 466:
Page 467 and 468:
Page 469 and 470:
Page 471 and 472:
show all

Environmental Impact Statement - Sonoma Land Trust

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

Delete template?

Save as template?