1. Sediment & Hydraulic Challenges in the City of Livermore December 11, 2008 Sediment Forum Alameda Creek Watershed

2. Location 30 miles of creeks and tributaries in the City of Livermore Three main creeks: Arroyo Las Positas Arroyo Mocho Arroyo Del Valle Watershed Area of three main creeks is approx. 200 sq. miles

3. Sediment along the Arroyo Las Positas and Arroyo Mocho

4. Sediment along the Arroyo Mocho

5. Arroyo Mocho at Concannon Bridge (Location #1)

6. Arroyo Mocho Upstream of Robertson Park (Location #1)

7. Arroyo Mocho at Arroyo Road (Location #2)

8. Arroyo Mocho at Arroyo Road (Location #2)

9. Arroyo Mocho at Holmes Street Bridge (Location #3)

10. Arroyo Mocho at Holmes Street (Location #3)

11. Arroyo Mocho at Holmes Street (Location #3)

12. Arroyo Mocho along Murrietta Boulevard (Location #4)

13. Arroyo Mocho Under Stanley Avenue Railroad Bridge (Location #4)

14. Sediment along the Arroyo Las Positas

15. Arroyo Seco – Charolette Avenue (Location #5)

16. Altamont Creek at Vasco Road (Location #6)

17. Altamont Creek looking toward the Garavanta Mitigation Area At Vasco Road (Location #6)

18. Arroyo Las Positas near Springtown Golf Course (Location #7)

19. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas near Las Colinas Road (Location #8)

20. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas near Las Colinas Road (Location #8)

21. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas at Livermore Avenue (Location #9)

22. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas at Livermore Avenue (Location #9)

23. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas near Livermore Avenue (Location #9)

24. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas at Livermore Avenue (Location #9)

25. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas near Livermore Avenue (Location #9)

26. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas near Livermore Avenue (Location #9)

27. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas near Cayatano Creek (Location #10)

28. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas at Cayatano Creek (Location #10)

29. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas upstream of Isabel Avenue (Location #11)

30. Sediment along the Arroyo Las Positas Arroyo Las Positas looking toward Isabel Avenue/Kittyhawk Road (Location #11)

31. Sediment along the Arroyo Las Positas

32. Collier Creek By-Pass Pipes upstream of Mitigation Area near Las Positas College (Location #12)

33. Collier Creek Mitigation Area Across from College (Location #12)

34. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas at Collier Creek (Location #13)

35. Arroyo Las Positas Upstream of Airway Blvd. (Location #13)

36. Arroyo Las Positas Upstream of Airway Boulevard (Location #13)

37. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas – Las Positas Golf Course (Location #14)

38. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas – Las Positas Golf Course (Location #14)

39. Sediment along the Arroyo Las Positas and Arroyo Mocho Arroyo Las Positas – Las Positas Golf Course (Location #14)

40. Arroyo Las Positas Upstream of Realignment (Location #15)

41. Arroyo Las Positas Downstream of Golf Course (Location #15)

42. Arroyo Las Positas Realignment Project by County of Alameda (Location #16)

43. Arroyo Las Positas at El Charro Road (Location #17)

44. El Charro Specific Plan Project

45. Approved Project

46. Area Constraints

47. Flood Control Regional Flood Control Diversion proposed to relieve flooding and erosion downstream Cost estimated at $170 Million Reference: Zone 7 Stream Management Master Plan

48. Early Proposal with Regional Phase 1 Flood Control Diversion

49. Regional Phase 1 to 4 Flood Control Diversion

50. Infrastructure Design $80 Million savings in Regional Flood Control Costs 12% of the regional diversion to be built as Phase I within two years with the El Charro Specific Plan Infrastructure

51. Questions? Sediment and Hydraulic Challenges In the City of Livermore