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Helemano 6 Reservoir, Oahu water level history

Daily records since 2009 · Level today: 22.73 ft

Highest on record
30.87 ft
Mar 20, 2026
Lowest on record
19.51 ft
Mar 23, 2026
Today
22.73 ft
Oct 23, 2026
Years of data
18
since 2009

In short

Across 16 complete years, 2024 had the lowest average level (22.36 ft) and 2022 the highest (23.80 ft).

On average the lake is lowest in December (22.74 ft) and highest in July (23.33 ft).

Helemano 6 Reservoir, Oahu level, all years

Loading chart…

Measured Normal range for the date (middle 50% of past years)

Each year's lowest and highest level

192225283220092011201320152017201920212023202520262009: lowest 19.87 ft (2009-11-09), highest 25.99 ft (2009-05-01), average 22.81 ft, 296 days measured2010: lowest 19.59 ft (2010-12-22), highest 24.99 ft (2010-02-18), average 23.28 ft, 358 days measured2011: lowest 19.59 ft (2011-01-19), highest 27.76 ft (2011-01-13), average 22.59 ft, 365 days measured2012: lowest 19.77 ft (2012-05-26), highest 24.59 ft (2012-12-06), average 23.04 ft, 366 days measured2013: lowest 19.60 ft (2013-12-08), highest 24.65 ft (2013-11-09), average 22.97 ft, 365 days measured2014: lowest 19.91 ft (2014-10-25), highest 25.81 ft (2014-03-16), average 23.01 ft, 363 days measured2015: lowest 19.60 ft (2015-10-21), highest 25.77 ft (2015-11-24), average 22.37 ft, 360 days measured2016: lowest 19.60 ft (2016-09-03), highest 26.81 ft (2016-07-25), average 23.11 ft, 366 days measured2017: lowest 19.60 ft (2017-12-26), highest 25.42 ft (2017-04-30), average 23.41 ft, 365 days measured2018: lowest 19.58 ft (2018-12-28), highest 26.04 ft (2018-10-07), average 22.60 ft, 359 days measured2019: lowest 19.58 ft (2019-01-02), highest 27.78 ft (2019-12-15), average 22.99 ft, 357 days measured2020: lowest 19.58 ft (2020-01-25), highest 27.18 ft (2020-07-05), average 23.46 ft, 366 days measured2021: lowest 19.74 ft (2021-04-05), highest 26.67 ft (2021-12-07), average 22.95 ft, 356 days measured2022: lowest 21.25 ft (2022-01-27), highest 27.45 ft (2022-07-22), average 23.80 ft, 365 days measured2023: lowest 19.66 ft (2023-01-12), highest 26.61 ft (2023-11-07), average 23.26 ft, 365 days measured2024: lowest 19.68 ft (2024-04-04), highest 28.79 ft (2024-05-17), average 22.36 ft, 355 days measured2025: lowest 21.52 ft (2025-02-09), highest 25.47 ft (2025-12-19), average 22.89 ft, 357 days measured2026: lowest 19.51 ft (2026-03-23), highest 30.87 ft (2026-03-20), average 22.75 ft, 294 days measured
1922252832200920132017202120262009: lowest 19.87 ft (2009-11-09), highest 25.99 ft (2009-05-01), average 22.81 ft, 296 days measured2010: lowest 19.59 ft (2010-12-22), highest 24.99 ft (2010-02-18), average 23.28 ft, 358 days measured2011: lowest 19.59 ft (2011-01-19), highest 27.76 ft (2011-01-13), average 22.59 ft, 365 days measured2012: lowest 19.77 ft (2012-05-26), highest 24.59 ft (2012-12-06), average 23.04 ft, 366 days measured2013: lowest 19.60 ft (2013-12-08), highest 24.65 ft (2013-11-09), average 22.97 ft, 365 days measured2014: lowest 19.91 ft (2014-10-25), highest 25.81 ft (2014-03-16), average 23.01 ft, 363 days measured2015: lowest 19.60 ft (2015-10-21), highest 25.77 ft (2015-11-24), average 22.37 ft, 360 days measured2016: lowest 19.60 ft (2016-09-03), highest 26.81 ft (2016-07-25), average 23.11 ft, 366 days measured2017: lowest 19.60 ft (2017-12-26), highest 25.42 ft (2017-04-30), average 23.41 ft, 365 days measured2018: lowest 19.58 ft (2018-12-28), highest 26.04 ft (2018-10-07), average 22.60 ft, 359 days measured2019: lowest 19.58 ft (2019-01-02), highest 27.78 ft (2019-12-15), average 22.99 ft, 357 days measured2020: lowest 19.58 ft (2020-01-25), highest 27.18 ft (2020-07-05), average 23.46 ft, 366 days measured2021: lowest 19.74 ft (2021-04-05), highest 26.67 ft (2021-12-07), average 22.95 ft, 356 days measured2022: lowest 21.25 ft (2022-01-27), highest 27.45 ft (2022-07-22), average 23.80 ft, 365 days measured2023: lowest 19.66 ft (2023-01-12), highest 26.61 ft (2023-11-07), average 23.26 ft, 365 days measured2024: lowest 19.68 ft (2024-04-04), highest 28.79 ft (2024-05-17), average 22.36 ft, 355 days measured2025: lowest 21.52 ft (2025-02-09), highest 25.47 ft (2025-12-19), average 22.89 ft, 357 days measured2026: lowest 19.51 ft (2026-03-23), highest 30.87 ft (2026-03-20), average 22.75 ft, 294 days measured
Lowest to highest that yearYear average2026 so far

One bar per year from the lowest to the highest daily level, with the year's average. Years with no bar have no daily record in the agency archive.

Lowest years

Years ranked by their lowest daily level.

  • 202019.58 ft on Jan 25
  • 201919.58 ft on Jan 2
  • 201819.58 ft on Dec 28
  • 201119.59 ft on Jan 19
  • 201019.59 ft on Dec 22

Yearly highs and lows

YearAverageLowLow dateHighHigh date
2026 (294 days)22.7519.51Mar 2330.87Mar 20
202522.8921.52Feb 925.47Dec 19
202422.3619.68Apr 428.79May 17
202323.2619.66Jan 1226.61Nov 7
202223.8021.25Jan 2727.45Jul 22
202122.9519.74Apr 526.67Dec 7
202023.4619.58Jan 2527.18Jul 5
201922.9919.58Jan 227.78Dec 15
201822.6019.58Dec 2826.04Oct 7
201723.4119.60Dec 2625.42Apr 30
201623.1119.60Sep 326.81Jul 25
201522.3719.60Oct 2125.77Nov 24
201423.0119.91Oct 2525.81Mar 16
201322.9719.60Dec 824.65Nov 9
201223.0419.77May 2624.59Dec 6
201122.5919.59Jan 1927.76Jan 13
201023.2819.59Dec 2224.99Feb 18
2009 (296 days)22.8119.87Nov 925.99May 1

Levels in feet. Partial years show the number of days with data.

Monthly averages

MonthAverageLowestHighest
January22.8519.5827.76
February22.7819.5926.17
March22.9019.5130.87
April22.9119.5226.35
May23.1119.5428.79
June22.9419.6026.51
July23.3319.6027.45
August22.9819.6025.51
September23.1919.6026.83
October23.0619.6027.69
November23.0219.8726.61
December22.7419.5827.78

Download

Daily levels as CSV (6,378 rows; credit the original agencies listed below)