4238.01 ft NAVD88
level 22.9 ft below full pool — on the low side for mid-August
Reading comes straight from U.S. Army Corps of Engineers Access to Water data (USACE series Sumner.Elev.Inst.15Minutes.0.DCP-rev) and updates live when you load this page.
Lake Sumner through the year
The band is the lake's own normal: where the level has run on each calendar day, 1999–2026. The summer drawdown — and how this year sits in it — shows up without reading a single number.
This year vs the years that matter
This year's trace against last year and the driest and wettest years on record — the drought-context question every lake regular asks.
- 2026 (this year)
- 2025 (last year)
- 2015 (wettest on record)
- 2012 (driest on record)
Full pool, datum, and the gauge
"Full pool" here means the conservation pool — the level the lake is designed to hold for water supply and recreation, not the flood-control space above it. The full explainer covers flood pool and dead pool too.
| Full pool | 4260.88 ft NAVD88 · per Bureau of Reclamation (Sumner Dam) full-pool reference |
|---|---|
| Conservation capacity | 35,917 acre-feet · per Bureau of Reclamation (Sumner Dam) capacity reference |
| Gauge | USACE series Sumner.Elev.Inst.15Minutes.0.DCP-rev · U.S. Army Corps of Engineers Access to Water data |
| Datum | NAVD88 — 4260.88 ft is the district's top of conservation pool figure, in the same NAVD88 datum as the gauge. |
| Last verified | August 20, 2026 |
LakeDates reports lake level, not ramp status. Whether a given ramp or marina is usable at this level varies ramp by ramp — call the marina before you tow.
Quick answers
How full is Lake Sumner right now?
Lake Sumner is at 4238.01 ft (NAVD88) as of August 20, 2026 — 22.9 ft below full pool — on the low side for mid-August
Is Lake Sumner full?
Not quite — at 4238.01 ft, Lake Sumner is 22.9 ft below its full pool of 4260.88 ft (NAVD88).
What is full pool for Lake Sumner?
Full pool (the conservation pool) for Lake Sumner is 4260.88 ft NAVD88, per Bureau of Reclamation (Sumner Dam) full-pool reference. Levels above it use flood storage; levels below it are drawdown.