What is the current water level of Rock Island Pp Tw Unit 1?

As of Jun 30, 2026, 4:15 PM (UTC-07:00), the pool elevation was 573.47 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.

Is Rock Island Pp Tw Unit 1 full right now?

Its managing agency does not publish a %-of-conservation-pool-full figure for this lake, so we show the bare level rather than estimate one.

Where does this data come from?

From USGS site 12462560, retrieved Jul 14, 2026, 10:55 PM (UTC+00:00). See the official link and the methodology page for the full source and update cadence.

Is this safe to use for boating or navigation?

No. Levels here are provisional readings for general reference only — not for navigation, dam-safety, or other safety decisions. Always confirm current conditions with the managing agency before making those calls.

Rock Island Pp Tw Unit 1 water level — Washington

Washington · USGS · reading Jun 30, 2026, 4:15 PM (UTC-07:00) Provisional

Rock Island Pp Tw Unit 1 in Washington was last measured at 573.47 ft (datum NGVD29), as of Jun 30, 2026, 4:15 PM (UTC-07:00) (USGS Water Services). Over its recent trend window the level has been rising (+0.6 ft). This reading is provisional and subject to revision. Figures are provisional readings for reference — not for navigation or safety decisions.

Current reading Rock Island Pp Tw Unit 1 · Washington

Pool elevation: 573.47 ft
% of conservation pool full: Not reported
Storage: Not reported
Recent trend: ↑Rising

Recent trend

The last ~76 days of readings at this station, downsampled for display.

Data: USGS Water Services (waterservices.usgs.gov) and USACE CWMS Data (cwms-data.usace.army.mil), retrieved 2026-07-14. Both public domain (a work of the U.S. Government, 17 U.S.C. §105).

Important — not for navigation or safety decisions

Water levels here are provisional readings for general reference only. Conditions vary and readings can be revised. Always confirm current conditions with the managing agency before making navigation, boating, or dam-safety decisions.

Source: USGS site 12462560, retrieved Jul 14, 2026, 10:55 PM (UTC+00:00). Official page for this lake →

Nearby lakes

The six nearest published lakes by centroid distance (great-circle) — cross-state neighbors included.

Lakes nearest to Rock Island Pp Tw Unit 1, with current level and distance.
Lake	State	Level	Distance
Rock Island Dam Pp North Hw	WA	612.39 ft	0 km
Rocky Reach Hw Unit 10w	WA	706.53 ft	26 km
Soap Lake	WA	1,069.13 ft	46 km
Lenore Lake	WA	1,077.62 ft	48 km
Moses Lake at Moses Lake	WA	1,046.73 ft	64 km
Franklin Roosevelt Lake	WA	1,274.57 ft	107 km

Frequently asked questions

What is the current water level of Rock Island Pp Tw Unit 1?: As of Jun 30, 2026, 4:15 PM (UTC-07:00), the pool elevation was 573.47 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.
Is Rock Island Pp Tw Unit 1 full right now?: Its managing agency does not publish a %-of-conservation-pool-full figure for this lake, so we show the bare level rather than estimate one.
Where does this data come from?: From USGS site 12462560, retrieved Jul 14, 2026, 10:55 PM (UTC+00:00). See the official link and the methodology page for the full source and update cadence.
Is this safe to use for boating or navigation?: No. Levels here are provisional readings for general reference only — not for navigation, dam-safety, or other safety decisions. Always confirm current conditions with the managing agency before making those calls.

More in Washington

See every lake tracked in Washington, or read the methodology behind these figures.