Monthly Water Tracker | Santa Clara Valley Water
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Monthly Water Tracker


As of December 1, 2018

We began calendar year 2018 with groundwater storage well within Stage 1 (Normal) of the District’s Water Shortage Contingency Plan. This year’s (beginning September 1, 2017, and ending August 31, 2018) precipitation was 60% of average at the San Jose Index Station and well below average for the Santa Cruz Mountains, South County, and the Diablo Range. The snow water equivalent for the Northern Sierra was considerably below normal.

Despite below normal local rainfall and below normal statewide snow pack, end of year groundwater storage for 2018 is projected to be relatively high, well within Stage 1 (Normal) due to carryover supplies from a wet 2017.

Related Files
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Water Tracker December 2018.pdf 372.77 KB


  • Rainfall in Santa Clara County
  • Month of November, City of San Jose: 1.65 inches
  • The average daily high temperature for November was 69 degrees Fahrenheit. Temperatures were above normal for the month

Local Reservoirs

Current local reservoir storage

  • Total December 1 storage: 45,274 acre-feet

    • 66% of 20-year average for that date
    • 27% of total capacity
    • 40% of restricted capacity (166,808 acre-feet total storage capacity limited by seismic restrictions to 111,963 acre-feet)
  • Approximately 131 acre-feet imported water was delivered into local reservoirs during November 2018
  • Total estimated releases to streams (local and imported water) during November was 5,600 acre-feet


Groundwater Storage:  Total storage at the end of 2018 is predicted to fall within Stage 1 (Normal) of the district's Water Shortage Contingency Plan

Table of groundwater sub-basin levels for the month

Imported Water

  • 2018 State Water Project (SWP) and Central Valley Project (CVP) allocations:
    • 2018 SWP allocation of 35%, providing 35,000 AF to the District
    • 2018 South-of-Delta CVP allocations:
      • The M&I allocation is currently 75% and the Agricultural allocation is 50%, which provides 114,050 AF to the District
  • Initial 2019 SWP allocation of 10%, 10,000 acre-feet, announced on November 30, 2018
  • State-wide reservoir storage information, as of December 2, 2018:
    • Shasta Reservoir at 48% of capacity (80% of average for this date)
    • Oroville Reservoir at 29% of capacity (48% of average for this date)
    • San Luis Reservoir at 58% of capacity (97% of average for this date)
  • District’s Semitropic groundwater bank reserves are at 82% of capacity, or 292,725 acre-feet as of October 31, 2018
  • Estimated SFPUC deliveries to Santa Clara County:
    • Projected month of October = 4,630 acre-feet
    • 2018 Total to Date = 39,223 acre-feet
    • Five-year annual average is 48,700 acre-feet
  • Board Governance Policy No. EL-5.3.3 includes keeping the Board informed of imported water management activities on an ongoing basis.  In CY 2018, four imported water management agreements were executed as of November 30, 2018

Treated Water

  • Above average demands of 7,955 acre-feet delivered in November
  • This total is 115% of the five-year average for the month of November
  • Year-to-date deliveries = 102,028 acre-feet or 105% of the five-year average

Conserved Water

  • Saved 75,000 acre-feet in FY18 from long-term program (baseline year is 1992)
  • Long-term program goal is to save nearly 75,000 acre-feet in FY18
  • The Board has called for a 20% reduction and a limit of three days per week for irrigation of ornamental landscape with potable water
  • Achieved a 20% reduction in water use through the first ten months of 2018, compared to 2013
  • Monthly Water Use Report

Recycled Water

  • Estimated November 2018 production = 1,000 acre-feet
  • Estimated Year-to-Date through November = 18,800 acre-feet or 101% of the five-year average
  • Silicon Valley Advanced Water Purification Center produces purified water that is blended with existing tertiary recycled water for South Bay Water Recycling Program's customers.  The plant produced 1.3 billion gallons (4,000 acre-feet) of purified water in 2017 and 3,500 acre-feet since the beginning of 2018