Groundwater Status Report, WY 2015

Transcription

1 Groundwater Status Report, WY 2015 Christina Buck, PhD Water Resources Scientist Water Commission February 3, 2016

2 2 Groundwater Status Report Combines: 1. Groundwater Status Report for Water Year Basin Management Objectives for 2016

3 3 Groundwater Status Report Hydrologic Conditions Precipitation Water year types Feather River Diversions Groundwater Conditions Monitoring frequency and period of record Groundwater quality trend monitoring Land subsidence Well Permits Groundwater level monitoring

4 8 Station Index for 2015 WY inches 74.4% of Average

5 Sacramento Valley Water Year Type Index WY 2015 Critical

6 Annual Precipitation- Western Canal climate station 6 WY inches

7 7 Daily Precipitation Durham CIMIS station Storms in December and February. Significant winter irrigation likely unnecessary

8 Feather River Diversions (AF) Water Year Western Canal Joint Water Water District Districts Board* TOTAL , ,018 1,032, , ,489 1,021, , , , , , , , ,663 1,120, , ,128 1,034, , ,345 1,038, , ,286 1,142, , ,748 1,073, , ,693 1,038, , ,518 1,002, , ,771 1,007, , ,671 1,015, , ,560 1,055, , , , , , ,056 50% Curtailment to Feather River Settlement Contractors, first time in 23 years. * Joint Water Districts Board includes Biggs-West Gridley Water District, Butte Water District, Richvale Irrigation District, and Sutter Extension Water District. 8

9 9 Water Quality Trend Monitoring Purpose: Provide baseline data and evaluate for evidence of saline intrusion All 13 wells sampled July 21-28, 2015 Temperatures remained relatively consistent in all water samples All samples were within the acceptable range for ph All samples were within the acceptable range for electrical conductivity No evidence of saline intrusion Report included as Appendix D

10 Units: feet, from daily data 10 Land Subsidence No inelastic land subsidence has been recorded in Butte County 20N01E18L001M 19N01E35B002M 18N01E35L001M

11 11 Issued Well Permits** Well Type Small Diameter Large Diameter Well Repairs & Deepening ** Number of well permits issued by Butte County Environmental Health, not necessarily wells actually drilled. Over ~14,000 wells exist in the county

12 12 Groundwater Level Monitoring- Basin Management Objective Program 127 unique wells monitored and tracked 77 assigned alert stage 59 equipped with data loggers that record water levels hourly Data available from CASGEM and also the Water Data Library Summarized in BMO spreadsheets in Appendix E

13 13

14 14

15 A p p e n d i x B 15

16 A p p e n d i x B 16

17 17 Groundwater Conditions Spring: March > 2015 compared Well Count Change (ft) SIU 106 Average GWL Change 0.1 Median GWL Change Average Increase 2 Median Increase 1 Max Increase 11 Vina 59 Average Decrease -1 Median Decrease -1 Max Decrease -7 Cherokee

18 18 Groundwater Conditions Fall: October > 2015 compared Well Count Change (ft) SIU 113 Average GWL Change -2 Median GWL Change Average Increase 4 Median Increase 0.8 Max Increase 16 North Yuba 88 Average Decrease -3 Median Decrease -2.3 Max Decrease -8 North Yuba

19 19

20 20 BMO Alert Stage Frequency Spring: March Alert Alert Total Fall: October Alert Alert Total

21 A p p e n d i x C 21

22 Spring 2015 with Water Source 22

23 23 Fall wells measured 69 alert stages assigned 8 No Measurement 5 Questionable Measurement 16 Alert 1 25 Alert 2

24 24 Appendix F: Groundwater Change Map ft deep wells

25 Groundwater Level Trends Durham Dayton: Domestic, shallow (<200 ft.) well in Modesto Formation. Record begins in Change from 2014 Spring:-0.5 ft Fall: -0.6 ft

26 Groundwater Level Trends Vina: Domestic, shallow (<200 ft.) well in Modesto Formation. Record begins in Change from 2014 Spring:-2.1 ft Fall: -0.7 ft

27 Groundwater Level Trends Western Canal: Domestic, shallow/intermediate (<200/ ft.) well in Alluvial system. Record begins in Change from 2014 Spring:-1.2 ft Fall: +0.7 ft

28 28 Summary 2015 was a critical water year in the Sacramento Valley and the fourth year of drought Annual precipitation was 74% of long term average Record warm temperatures during winter storm season led to rain, little snow. 5% of Average April 1 snowpack. Surface water curtailments and 50% cutback to Feather River Settlement Contractors Generally small decline in groundwater levels from Median -0.3 foot decline spring to spring Median -1.6 foot decline fall to fall For local conditions, see spring/fall graphs in BMO reports. GWLs highly variable throughout the county. No indication of saline intrusion into the basin. No recorded inelastic subsidence in Butte County from extensometers

29 29 Appendices Well numbering system explained (A) Monitoring and CASGEM Network Maps (B) Alert Stage Maps (C) Water Quality Trend Monitoring report (D) Spring, Summer, and Fall data tables(e) DWR groundwater level contour and change maps (F) BMO reports (G)

30 30 Acknowledgements Technical Advisory Committee CA DWR and Northern Region Office Butte County Department of Environmental Health Western Canal Water District Joint Districts Board

31 Questions? / Discussion 31

32 Groundwater Conditions 2014 WY Spring: March > 2014 compared 32 Fall: October > 2014 compared