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Surface Water Data Portal

Demo snapshot · July 28, 2026 at 4:53 PM PT · not current conditions

Reservoirs

Vasona Reservoir

Holding 440 acre-feet, which is 110.1 percent of its published capacity of 400 acre-feet.

Vasona Reservoir plotted at latitude 37.2463 and longitude -121.9650 over Valley Water's published major-watershed layer.
Vasona Reservoir at 37.2463, -121.9650, exactly as positioned in Valley Water's sensor feed. Guadalupe River is the published polygon whose name matches this portal group. The eleven published polygons do not exactly match the portal's five sensor groups and do not provide a boundary for every named creek.
  • Reservoir

110.1%

  • Storage 440 acre-feet
  • Water surface elevation 294.4 ft
  • Spills at 294.8 ft
  • Guadalupe watershed
  • Captured July 28, 2026 at 4:30 PM PT

Reservoir Notes

Elevation data is in 'local' datum, which is similar, but not exactly, in NGVD29 datum. To convert the local datum to NAVD88, add 2.47'.

Valley Water, sensor notes for Vasona Reservoir