436.78 ft above mean sea level
79% full share of conservation capacity, as reported with the gauge reading
level 3.2 ft below full pool — typical for mid-August
Reading from Texas Water Development Board — Water Data for Texas (Water Data for Texas — jim-chapman); it refreshes with each site update rather than live.
Jim Chapman Lake through the year
The band is the lake's own normal: where the level has run on each calendar day, 2000–2026. 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)
- 2001 (wettest on record)
- 2006 (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 | 440.00 ft above mean sea level · per Water Data for Texas — Jim Chapman Lake |
|---|---|
| Conservation capacity | 258,723 acre-feet · per Water Data for Texas — Jim Chapman Lake |
| Gauge | Water Data for Texas — jim-chapman · Texas Water Development Board — Water Data for Texas |
| Datum | ft above mean sea level |
| 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 Jim Chapman Lake right now?
Jim Chapman Lake is at 436.78 ft (above mean sea level) as of August 20, 2026 — 3.2 ft below full pool — typical for mid-August The lake is holding 79% of its conservation capacity.
What percent full is Jim Chapman Lake?
As of August 20, 2026, Jim Chapman Lake is holding 79% of its conservation capacity, per Water Data for Texas — Jim Chapman Lake.
Is Jim Chapman Lake full?
Not quite — at 436.78 ft, Jim Chapman Lake is 3.2 ft below its full pool of 440.00 ft (above mean sea level). The lake is holding 79% of its conservation capacity.
What is full pool for Jim Chapman Lake?
Full pool (the conservation pool) for Jim Chapman Lake is 440.00 ft above mean sea level, per Water Data for Texas — Jim Chapman Lake. Levels above it use flood storage; levels below it are drawdown.