Seawater Intrusion Program and Update

Transcription

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2 Coastal Salinas Valley Seawater Intrusion Program and Update Page 1

3 Today s Presentation How Seawater Intrusion (SWI) Works Agency Projects to Combat SWI Coastal Monitoring Program 2011 SWI Front Maps Questions Page 2

4 Cross Section Near the Coast 180 Ft. Aquifer 400 Ft. Aquifer Page 3 Deep Aquifer

5 Projects to Combat Seawater Intrusion Nacimiento Dam (1957) SanAntonio Dam (1965) Castroville Seawater Intrusion Project (CSIP) & SVRP (1997) Recycled water is delivered to intruded areas to reduce ground water pumping Water delivered averages 13,000 acre feet per year Sli Salinas Valley Water Project (SVWP) (2010) Nacimiento Spillway Modification SalinasRiverDiversion Facility (SRDF) Page 4

6 Lake Nacimiento Completed in 1957 Lake Capacity 377,900 AF Page 5

7 Lake San Antonio Completed in 1965 Lake Capacity 335,000 AF Page 6

8 CSIP & SVRP Salinas Castroville Monterey Bay Completed 1997 Average Delivery 13,000AF/Yr Page 7

9 Salinas Valley Water Project Nacimiento Spillway Modification Sli Salinas River Diversion i Facility Page 8

10 Seawater Intrusion Data Monitoring Ground Water Wells Sampled annually during peak pumping 90 Agricultural wells sampled 2 3 times 17 Dedicated monitoring wells sampled Analyzed for General Minerals Page 9

11 Seawater Intrusion Data (cont.) Data Evaluation Historical Chloride & Conductivity Trends Stiff and Piper Diagrams Anion/ Cation Shifts Data Development Process Water quality Well construction Well pumping Ground water level contours Page 10

12 Chloride & Conductivity Time Series Indicating Intrusion Chlori ide (mg/l) S/02E 34XXX Chloride > 360 mg/l Chloride 21 mg/l vity (us/cm m) Conducti Chloride Conductivity Page 11

13 No Intrusion Cations meq/kg Anions Mg SO 4 Stiff Ca HCO 3 + CO 3 Diagrams Na + K Cl Early Intrusion Cations meq/kg Anions Mg SO 4 Ca HCO 3 + CO 3 Na + K Cl Page 12

14 Piper Diagram Indicating Phase I Intrusion Chloride > 360 mg/l Chloride 21 mg/l Page 13

15 Chloride vs. Na/Cl Molar Ratio S/03E 19XXX 2.5 Chlo oride (mg/l L) Chloride 21 mg/l Chloride > 360 mg/l r) Na/Cl Ratio (mola Page 14

16 Seawater Intrusion Data (cont.) LbR Lab Results are Evaluated d& Uploaded dinto WRAIMS database annually 500 mg/l Contours are Developed from the Odd Year Data & Added to the Historic SWI Maps Page 15

17 2011 Pressure 180 Foot Aquifer 500 mg/l Chloride Areas Page 16

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19 Pressure 180 Foot Aquifer Historical Advancement 30,000 25,000 20, Estimated Acreage Overlying Seawater Intrusion Pressure 180-Foot Aquifer 19,817 21,619 24,019 24,78025,407 27,175 27,600 27,791 28,142 Acreage 15,000 10, ,672 11,645 16,221 5,000 1,833 0 Cumulative Advance Source: MCWRA Graph Date: 08/27/12 Page 18

20 Pressure 180 Foot Aquifer ion Pressure 180-Foot Aquifer Historical Advancement 24,780 24,019 27,175 27,60027,79128,142 25,407 19, ,619 16,221 11, Year Page 19

21 2011 Pressure 400 Foot Aquifer 500 mg/l Chloride Areas Page 20

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23 Pressure 400 Foot Aquifer Historical Advancement 15,000 Estimated Acreage Overlying SeawaterIntrusion Pressure 400-Foot FootAquifer 12,000 9,961 12,573 11,523 11,88212,004 12,097 11,003 10,504 Acreage 9,000 6,000 7,521 8,347 9,065 8,658 3,717 3, Cumulative Advance Source: MCWRA Graph Date: 08/27/12 Page 22

24 Pressure 400 Foot Aquifer mated Acreage Overlying rusion Pressure 400-Foot Aquifer Historical Advancement 7,521 8,347 8,658 9,065 10,50 411,003 9, ,573 11, , , ,097 3, Page 23

25 Summary How Seawater Intrusion (SWI) Works Agency Projects to Combat SWI Coastal Monitoring Program 2011 SWI Front Maps Page 24

26 Conclusion Seawater Intrusion (2009 to 2011) Rate of SWI continues to decrease Advancement minimal, lobes are broadening Complex mechanism for SWI persists Page 25

27 The water came in a thirty-year cycle. There would be five to six wet and wonderful years when there might be nineteen to twenty-five inches of rain, and the land would shout with grass. Then would come six or seven pretty good years of twelve to sixteen inches of rain. And then the dry yyears would come And it never failed that during the dry years the people forgot about the rich years, and during the wet years they lost all memory of the dry years. It was always that way. John Steinbeck, East of Eden Page 26

28 Question?

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