Jonesville Lock and Dam Lower water level — Louisiana
Jonesville Lock and Dam Lower in Louisiana was last measured at 16.33 ft (datum NGVD29), as of Aug 31, 2026, 7:00 AM (UTC+00:00) (USACE CWMS Data). Over its recent trend window the level has been rising (+5.1 ft).
- % of conservation pool full
- Not reported
- Storage
- Not reported
- Recent trend
- ↑Rising
+5.1 ft over the trend window
Recent trend
Readings this station published between Jun 2, 2026 and Jun 23, 2026 — a 20-day window — downsampled for display.
Data: USGS Water Services (waterservices.usgs.gov) and USACE CWMS Data (cwms-data.usace.army.mil), retrieved 2026-08-31. Both public domain (a work of the U.S. Government, 17 U.S.C. §105).
Source: USACE MVK/Jonesville L&D-Lower, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for this lake →
The dam behind Jonesville Lock and Dam Lower
Jonesville Lock and Dam Lower is held back by Jonesville Lock and Dam , a concrete gravity structure, resisting the reservoir by its own weight alone , standing 94 ft high and running 920 ft along its crest , built across BLACK RIVER in Catahoula County , near SIMMESPORT . It was completed in 1972 , and is owned by USACE - Vicksburg District (a federal owner) , to a design credited to CEMVK.
Its recorded primary purpose is navigation — the pool is held inside a narrow band to keep a navigable depth, so large swings are rare by design . It also serves navigation;recreation;water supply.
It is founded on soil, with a earth core. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. The spillway opening is 450 ft wide.
NID classes it significant hazard potential: a failure would be expected to damage property and infrastructure rather than cost lives. It is a consequence rating, not a condition rating.
At its normal pool the reservoir covers about 7,120 acres. NID records a maximum storage of 149,300 acre-ft against a normal storage of 123,700 acre-ft. Its maximum discharge capacity is 176,000 cubic feet per second.
Dam facts: National Inventory of Dams record LA00175 , filed by US Army Corps of Engineers — U.S. Army Corps of Engineers, public domain. Water levels above come from USACE CWMS Data and are a separate source. (How this dam was matched to this gauge →)
Other gauges at this site
A second gauge reports at this same structure. Its readings are listed here rather than on a separate page, because it measures the same water.
| Gauge | Source | Elevation | Storage |
|---|---|---|---|
| Jonesville Lock and Dam Upper | USACE MVK/Jonesville L&D-Upper | 35.32 ft (NGVD29) | — |
How Jonesville Lock and Dam Lower compares nearby
4 of 6 nearby lakes with a current trend are also rising right now.
Nearby lakes
The six nearest published lakes by centroid distance (great-circle) — cross-state neighbors included.
| Lake | State | Level | Distance |
|---|---|---|---|
| Jonesville Lock and Dam Upper | LA | 35.32 ft | 0 km |
| Tensas Cocodrie Pump Landside | LA | 25.92 ft | 15 km |
| Larto Lake | LA | 36.57 ft | 16 km |
| Wild Cow Weir Upper | LA | 33.42 ft | 18 km |
| Catahoula Structure Landside | LA | 26.20 ft | 24 km |
| Catahoula Structure Riverside | LA | 17.55 ft | 24 km |
Frequently asked questions
- What is the current water level of Jonesville Lock and Dam Lower?
- As of Aug 31, 2026, 7:00 AM (UTC+00:00), the pool elevation was 16.33 ft (datum NGVD29). See the trend chart above for the recent direction.
- Is Jonesville Lock and Dam Lower 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 USACE MVK/Jonesville L&D-Lower, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00).
More in Louisiana
See every lake tracked in Louisiana, or read the methodology behind these figures.