Reservoir · Texas · United States · USGS NWIS
Lake J. B. Thomas
20.2% full
Capacity
247.44 hm³
Volume stored
50 hm³
Coordinates
32.593°N, 101.138°W
Last updated
2026-09-30
Current fill
20.2%vs 7 days ago
-0.4%losing
vs 1 year ago
-14.1%year-over-year
7-day trend
→stable
Data source: USGS National Water Information System (NWIS) — daily reservoir storage volume. Capacity is the design (normal full-pool) capacity from the US National Inventory of Dams (NID); fill % = current volume ÷ design capacity. Last reading: 2026-09-30.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 32.593, -101.138 · Open in Google Maps
About Lake J. B. Thomas
As of September 30, 2026, Lake J. B. Thomas is filled to 20.2% of its total capacity, holding roughly 50 hm³ of water out of a maximum 247 hm³. At this level the reservoir is low.
Over the most recent week on record the fill level has held broadly steady (-0.4 pts), and it is 14.1 points below its level on the same date a year earlier.
Across the readings we hold for Lake J. B. Thomas — 1461 data points between October 1, 2022 and September 30, 2026 — the level has ranged from a low of 16.7% (August 28, 2024) to a high of 43.8% (November 21, 2024). On average the reservoir is fullest around November and at its lowest around August.
It is operated by USGS primarily for multiple purposes. It lies within the Texas basin at 32.593°N, 101.138°W.
Key facts
- Current fill level
- 20.2%
- Water stored
- 50 hm³
- Total capacity
- 247 hm³
- 7-day change
- ▼ 0.4 pts
- Year-on-year
- ▼ 14.1 pts
- Primary use
- Multipurpose
- River basin
- Texas
- Operator
- USGS
- Coordinates
- 32.593°N, 101.138°W
- Last updated
- September 30, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 30 Sep 2026 | 20.2% | 50 |
| 29 Sep 2026 | 20.3% | 50 |
| 28 Sep 2026 | 20.3% | 50 |
| 27 Sep 2026 | 20.4% | 50 |
| 26 Sep 2026 | 20.4% | 51 |
| 25 Sep 2026 | 20.5% | 51 |
| 24 Sep 2026 | 20.5% | 51 |
| 23 Sep 2026 | 20.6% | 51 |
| 22 Sep 2026 | 20.6% | 51 |
| 21 Sep 2026 | 20.7% | 51 |
| 20 Sep 2026 | 20.8% | 51 |
| 19 Sep 2026 | 20.8% | 51 |