Chabot Dam Seismic Upgrade Spec Board of Directors March 8, 2016

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1 Chabot Dam Seismic Upgrade Spec 2107 Board of Directors March 8, 2016

2 Project Location NAB Hayward Fault Chabot Dam

3 Project Location North Chabot Reservoir 10,350 Acre-Ft Outlet Tunnel Hayward fault zone Chabot Dam

4 Chabot Dam and Outlet Works Outlet Works Outlet Tunnel 30 Blowoff Chabot Dam

5 Chabot Dam and Outlet Works Chabot Dam Outlet Works

6 Dam Constructed in 1875 Anthony Chabot ( ) April 1888

7 Project Need Division of Safety of Dams (DSOD) asked District to evaluate impacts from a Mw 7.25 earthquake on the nearby Hayward fault Findings: Earth dam could settle and displace several feet downslope Outlet works could collapse and become inoperable DSOD directed District to construct seismic upgrades to earth dam and outlet works

8 Earth Dam Seismic Upgrade Max Lake Level Expected displacements due to Mw 7.25 earthquake Existing Dam Max Lake Level 100-ft wide CDSM buttress to reduce seismic displacements Dam After Upgrade

9 Cement Deep Soil Mixing Buttress at Toe of Dam

10 Outlet Works Retrofit Existing Outlet Works Outlet Works After Retrofit Max Lake Level

11 Temporary Park Closures

12 San Leandro Creek Flows No impacts to creek during construction Will maintain current flows of 80 gpm (min) EBMUD working with CDFW to develop long-term strategy for fish flows in creek DWR Prop 1E (Stormwater Management) Grant received -$5 million; reservoir captures storm water runoff, reduces sediment to creek 30 Blowoff Discharge (max) San Leandro Creek below Dam

13 Unsuccessful attempt at a Pilot Project Labor Agreement PLA negotiating principles approved by Board on December 9, 2014 PLA approved by Board on January 12, 2016 Alameda County Building Trades Council declined to execute the negotiated PLA because it required: All qualified contractors and subcontractors to be permitted to bid and be awarded work regardless of MLA signatory status (Public Contract Code 2500) Waiver of union initiation fees upon request for contractors core workers who are not offered or who do not seek union membership

14 Project Phases and Dates Board certified EIR June 10, 2014 District finalized design December 2015 Advertised contract January 5, 2016 District approved Pilot PLA January 12, 2016 Opened bids February 10, 2016 Total of 6 bids; lowest effective responsible bidder is DMZ Builders, Inc. at $11,998,600

15 Next Steps Action Date Contract Award March 8, 2016 Issue Notice to Proceed April 2016 Close Parks/Start Field Work May 2016 Chabot Dam Earthwork Jun to Nov 2016 Outlet Works Retrofit Dec 2016 to May 2017 Contract Completion/Open Parks Summer 2017

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17 Water Supply Board Briefing Water Operations Department March 8, 2016

18 Water Supply Briefing California Water Supply Current Water Supply Water Supply Projections Water Supply Schedule 2

19 California Water Supply

20 California Water Supply Snow Surveys March 2015 March 2016 Michael Macor. SF Chronicle Rich Pedroncelli, AP DWR allocations are 30% for CY16 4

21 California Water Supply Automated Survey - Snow Water Equivalents Automated Snow Measurements Snow Water Equivalents Year % of Normal on March % % Snow station surveys conducted around March 1, 2016 Manual readings confirm preliminary automated measurements 5

22 California Water Supply Reservoir Storage March 7 March 7, 2016 Storage Average Storage on March 7 Storage on Feb 21 6

23 California Water Supply Folsom Lake Flood Releases 7

24 Current Water Supply 8

25 Current Water Supply Mokelumne Precipitation Rainfall Year 2016 Average

26 Current Water Supply East Bay Precipitation Rainfall Year 2016 Average

27 Current Water Supply Precipitation & Snow Add current photos East Bay As of 3/7/2016 Cumulative Precipitation % of Average East Bay Watershed % Mokelumne Basin 4-Station Average % Caples Lake Snow Depth % Caples Lake Snow Water Content % 11

28 Current Water Supply Caples Lake Snow Depth Historical Average Snow Depth (in) O N D J F M A M J Date 12

29 Current Water Supply Gross Water Production Year Avg of FY FY 2016 FY 2013 (184 MGD) FY 2016 Operational Estimate (149 MGD) 250 gross water production (mgd) Jul 1-Aug 1-Sep 1-Oct 1-Nov 1-Dec 1-Jan 1-Feb 1-Mar 1-Apr 1-May 1-Jun

30 Current Water Supply Water Savings Savings Rate (2013 Baseline) March 8, 2015 March 7, 2016 June 1, 2015 Feb 29, % 24% 14

31 Current Water Supply Reservoir Storage As of 3/7/16 Current Storage Percent of Average Percent of Capacity Pardee 181,480 AF 102% 92% Camanche 125,100 AF 45% 30% East Bay 127,160 AF 93% 84% Total System 433,740 AF 73% 57% 15

32 Water Supply Projections

33 Water Supply Projections (Runoff Projections as of March 8, 2016) Forecast Annual Runoff Total System Storage (on Sept 30, 2016) No Rain To-Come 490 TAF 420 AF 95% Exceedance (9.5 of 10 years are wetter) 90% Exceedance (9 of 10 years are wetter) 50% Exceedance (5 of 10 years are wetter) 10% Exceedance (1 of 10 years is wetter) 610 TAF 515 TAF 640 TAF 535 TAF 740 TAF 630 TAF 980 TAF 630 TAF Average Year 745 TAF 630 TAF 17

34 Proposed DMP Guidelines Demand Management Program Guidelines Include four stages of drought Allow for rationing >15% in extreme situations Stage Projected TSS (TAF) Quantity of CVP and Supplemental Supply Needed (Acre-Feet) District-Wide Water Use Reduction Goal 0 Normal 500 or more 0 Wise water use 1 Moderate Voluntary up to 15% 2 Significant ,000 Voluntary up to 15% 3 Severe ,000-65,000 Mandatory up to 15% 4 Critical <325 >65,000 Mandatory 15% 18

35 Water Supply Projections Mokelumne Precipitation Rainfall Year 2016 Wettest of Record 87.3 (RY83) RY 2016 To-Date % Exceedance Median Average % Exceedance Driest of Record 23.0 (RY77) 19

36 Water Supply Projections Precipitation Comparison 50 Precipitation (in) - Recent Years 45 Historical Avg 48.3 MEDIAN DRY Remainder Through Mar Through Mar

37 Water Supply End of September Storage MEDIAN 630 TAF 30 TAF Encroachment DRY 535 TAF 25 TAF SS 15 TAF Conservation 40 TAF SS 45 TAF Conservation 21

38 Water Supply Projections Weather Forecast 22

39 Water Supply Projections 10-Day NOAA Precipitation Probability Estimate ~70% Chance of Above-Normal Precipitation In the Mokelumne Watershed 23

40 Water Supply Projections 14-Day NOAA Precipitation Probability Estimate Likely Normal Precipitation In the Mokelumne Watershed 24

41 Water Supply Projections NOAA Precipitation Probability Estimate through May 33 to 40% Increased Chance of Above- Normal Precipitation In the Mokelumne Watershed 25

42 Water Year 2016 As of March 6, 2016 Mokelumne River basin runoff is 202 TAF Projected end of water year storage is TAF (90% - 10% exceedance) Mokelumne River watershed season to date precipitation is 108% of average East Bay watershed season to date precipitation is 95% of average Precipitation accumulation season 74% complete (26% remaining) 26

43 Water Year 2016 Water Supply Schedule Date Feb 2 Feb 23 Early March Mar 20 March to April April 1 April 26 Activity DWR February Snow Survey Drought Financial Impacts DWR March Snow Survey USBR Initial Allocation Water Supply Updates Continue public outreach DWR April Snow Survey Water Supply Availability and Deficiency Report Consider change in Drought Stage 27

44 St. Patrick s Day 2016 Luck? Total System Storage

45 WATER SUPPLY ENGINEERING DAILY REPORT RESERVOIR STORAGE AND ELEVATION WATER SURFACE STORAGE MAXIMUM CAPACITY Elevation +Gain +Gain Elevation Storage Release Spill MOKELUMNE Feet -Loss Ac-Ft -Loss Feet Ac-Ft Cfs Cfs Pardee Camanche EAST BAY Briones Chabot Lafayette San Pablo Upper San Leandro Total East Bay Res TOTAL SYSTEM STORAGE DISTRIBUTION SYSTEM MOKELUMNE SYSTEM DISTRIBUTION RESERVOIRS Storage Operating MG Flow Conditions MG Capacity Line SHUTDOWN Today Line THROTTLE Total Previous Day 353 Line THROTTLE Total Change -4 TOTAL Cfs FSCC to MOK AQUEDUCTS (Measured at Brandt), MG WATER PRODUCTION Million Capacity Mok 1 0 AND DEMAND Gallons MGD Mok 2 0 Lafayette WTP MG Orinda WTP RIVER FLOWS AND RELEASES Cfs San Pablo WTP Mokelumne River Natural Flow 4234 Sobrante WTP Pardee Reservoir Inflow 3187 Upper San Leandro WTP Pardee Release to Camanche Res Walnut Creek WTP Pardee Release to JVID Camanche Release to Mokel. River TOTAL SURFACE PRODUCTION Miscellaneous(Estimated) 0.4 PG&E CO. STORAGE (Acre-feet) TOTAL WATER PRODUCTION Maximum Change in Distribution System -4 Storage Change Capacity Wash Water from Distribution Sys. 1 Old Reservoirs SYSTEM DEMAND Salt Springs Res East-of-Hills Demand 23.5 Lower Bear Res West-of-Hills Demand 98.4 Total RAW WATER TRANSMISSION Ac-ft PRECIPITATION (Inches) INPUT DRAFT THIS YEAR AVERAGE YEAR Briones Res. 0 0 San Pablo Res STATION This Season Season Season U. San Leandro Res Today Month to-date to-date Total USL WTP TOTAL Orinda WTP REMARKS Lafayette Reservoir WID Canal Diversion = 62 cfs Walnut Creek WTP Mokelumne River below WID = 166 cfs Camp Pardee Salt Springs P.H CAPLES LAKE (7,830 FT) DATA PG&E data as of 4:00 pm previous date. All other data as of midnight. Snow Depth WTP capacities are sustainable rates. Water Content Today 78 Inches 28.8 Inches EAST BAY MUNICIPAL UTILITY DISTRICT AQUEDUCT DELIVERIES Average 74 Inches 27.2 Inches Monday, March 7, 2016

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