Alert 4/12/21 | 10:21 AM: Valley Water continues to operate safely while monitoring ongoing COVID-19 pandemic. LEARN MORE HERE
Your Water
Ensuring safe, reliable water
Your Water
Page Title
Your Water
Back to top

Monthly Water Tracker


As of May 1, 2021

Most of Santa Clara County is in a Severe Drought per the U.S. Drought Monitor. However, the county’s water supply is adequate for 2021. Despite well below-normal local rainfall and statewide snow pack, end of 2021 groundwater storage is projected to remain in Stage 1 (Normal) of the Water Shortage Contingency Plan. This is due to Valley Water’s strategy to address dry-year risks by securing emergency water supplies to boost groundwater recharge and 2022 San Luis Reservoir supplies; increasing the Landscape Conversion Rebate from $1 to $2 per square foot starting July 1; and ramping up conservation outreach. On April 27, the Board of Directors also increased the call for voluntary water use reduction from 20% to 25% compared to 2013. Valley Water will rely more on imported water and water conservation in the next 10 years while Anderson Reservoir storage is unavailable due to the Federal Energy Regulatory Commission (FERC) order.

Related Files
Attachment Size
Water Tracker May 2021.pdf 358.41 KB


  • Rainfall in Santa Clara County
  • Month of April, City of San José: 0.00 inch
  • Rainfall year total = 5.79 inches or 41% of average to date (rainfall year is July 1 to June 30)

      Snowfall in the Northern Sierra:

  • May 1 snowpack was 21% of normal for this date and 15% of April 1 average

Local Reservoirs

Current local reservoir storage

  • Total May 1 storage: 26,786 acre-feet

    • 26% of 20-year average for that date
    • 16% of total unrestricted capacity
    • 43% of restricted capacity (166,140 acre-feet total storage capacity limited by seismic restrictions to 62,362 acre-feet.  The restricted capacity includes the added FERC dam safety restriction on Anderson Reservoir effective October 1, 2020)
  • Approximately 750 acre-feet of imported water delivered into Calero Reservoirs during April 2021
  • Approximately 230 acre-feet of water released from Anderson Reservoir during April 2021.  Since the FERC order to drawdown Anderson Reservoir was issued on February 20, 2020, cumulative release from Anderson is approximately 29,880 acre-feet.  Anderson has reached deadpool.  Majority of released water was used for groundwater recharge and delivery to water treatment plants (based on preliminary hydrologic data).  Current releases are for water supply and environmental purposes
  • Total estimated releases to streams (local and imported water) during April was 4,580 acre-feet (based on preliminary hydrologic data)


Current groundwater conditions are in the normal range, but water levels and storage have declined  because of recent dry conditions.  Total storage at the end of 2021 is projected to be in the lower part of Stage 1 (Normal) of Valley Water’s Water Shortage Contingency Plan

Table of groundwater sub-basin levels for the month

Imported Water

  • 2021 State Water Project (SWP) and Central Valley Project (CVP) allocations:
    • 2021 SWP allocation of 5%, which provides 5,000 acre-feet to Valley Water
    • 2021 South-of-Delta CVP allocations are 55% for M&I and 5% for Agriculture, which provides 73,155 acre-feet to Valley Water.  The U.S. Bureau of Reclamation announced that the Agricultural water service contractors South-of-Delta allocation is not available for delivery until further notice
  • Statewide reservoir storage information, as of May 2, 2021:
    • Shasta Reservoir at 50% of capacity (58% of average for this date)
    • Oroville Reservoir at 42% of capacity (51% of average for this date)
    • San Luis Reservoir at 50% of capacity (57% of average for this date)
  • Daily current state-wide reservoir storage summary (map) (table)
  • Valley Water's Semitropic groundwater bank reserves are at 94% of capacity, or 329,551 acre-feet as of March 31, 2021
  • Estimated SFPUC deliveries to Santa Clara County:
    • Month of March = 3,525 acre-feet
    • 2021 Total to Date = 9,344 acre-feet
    • Five-year annual average = 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. No imported water agreements were executed under EL-5.3.3 since the last Water Tracker update

Treated Water

  • Above average demands of 7,858 acre-feet delivered in April
  • This total is 124% of the five-year average for the month of April
  • Year-to-date deliveries are 24,556 acre-feet or 110% of the five-year average

Conserved Water

  • Saved 74,198 acre-feet in FY20 from long-term program (baseline year is 1992)
  • Long-term program goal is to save nearly 100,000 acre-feet by 2030 and 110,000 acre-feet by 2040
  • The Board has called for a 25% reduction and a limit of three days per week for irrigation of ornamental landscape with potable water (resolution pending)
  • Through April, achieved an 11% reduction in water use in calendar year 2021, compared to 2013

Recycled Water

  • Estimated April 2021 production = 1,015 acre-feet
  • Estimated year-to-date through April = 3,490 acre-feet or 100% of the five-year average
  • Silicon Valley Advanced Water Purification Center produced an estimated 1.6 billion gallons (4,864 acre-feet) of purified water in 2020.  Since the beginning of 2021, about 1,090 acre-feet of purified water has been produced.  The purified water is blended with existing tertiary recycled water for South Bay Water Recycling Program customers

Alternative Sources

  • As of December 10, 2019, Valley Water's wastewater contract right from Palo Alto/Mountain View remains at 10,000 acre-feet/year