Hempstead Lake Water Level
New York · updated daily from the U.S. Geological Survey
21.67 ft
Hempstead Lake is high for this time of year and steady (-0.04 ft in the last 7 days).
Change since yesterday: -0.04 ft
Reading as of 2026-08-14 · higher than 89% of August readings on record
Where Hempstead Lake sits historically
Today's level compared with every reading in our 4.1-year record for this lake.
Since yesterday
-0.04 ft
7-day change
-0.04 ft
30-day change
+0.51 ft
1-year change
+0.46 ft
Last 30 days
Last 12 months
Full history (4.1 years)
Hempstead Lake records and averages
| Current level | 21.67 ft |
|---|---|
| Record high | 23.81 ft (2023-12-12) |
| Record low | 18.23 ft (2022-09-30) |
| Average of all readings | 20.99 ft |
| Data span | 4.1 years (1,514 readings) |
Frequently asked questions
Is Hempstead Lake full right now?
As of 2026-08-14, Hempstead Lake sits at 21.67 ft, which is high for this time of year.Over the past 30 days the level has risen 0.51 ft.
What is the water level at Hempstead Lake today?
The most recent reading is 21.67 ft (2026-08-14), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.
What is the highest Hempstead Lake has ever been?
The highest level in our records is 23.81 ft on 2023-12-12. The lowest is 18.23 ft on 2022-09-30. Our record covers about 4.1 years of readings.
Is Hempstead Lake low for this time of year?
Compared with every August in our records, the current level is higher than 89% of them — high 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.
Why is Hempstead Lake changing right now?
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. Hempstead Lake has risen 0.51 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.
How much has Hempstead Lake changed over the past year?
The level is +0.46 ft compared with this date last year (21.67 ft today). The full-history chart above covers 4.1 years, with a record high of 23.81 ft and a record low of 18.23 ft.
Nearby lakes in New York
Source: the U.S. Geological Survey. Readings are provisional and subject to revision by the publishing agency. All New York lake levels.