Upper Helemano Reservoir Water Level

As of 2026-08-14, Upper Helemano Reservoir sits at 35.73 ft, which is low for this time of year.Over the past 30 days the level has held steady 0.00 ft.

The most recent reading is 35.73 ft (2026-08-14), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.

The highest level in our records is 46.16 ft on 2026-03-20. The lowest is 33.25 ft on 2025-12-13. Our record covers about 5.0 years of readings.

Compared with every August in our records, the current level is higher than 0% of them — low for this time of year. Seasonal comparison matters more than the raw number, because most reservoirs draw down predictably through late summer and refill over winter and spring.

Reservoir levels move for four main reasons: rainfall and runoff into the basin, releases through the dam for downstream water supply, power generation or flood control, evaporation during hot months, and seasonal drawdown schedules set by the operating agency. Upper Helemano Reservoir has held steady 0.00 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.

The level is -2.74 ft compared with this date last year (35.73 ft today). The full-history chart above covers 5.0 years, with a record high of 46.16 ft and a record low of 33.25 ft.