Water elevation · USGS gauge 08039300 · updated August 29, 2026
Water elevation
155.29ft
feet above sea level
Gauge 08039300, Sam Rayburn Reservoir near Jasper, TX, operated by the U.S. Geological Survey. The value above is the most recent reading on file with its own timestamp. When the gauge answers, it is replaced by the current one — no estimate is ever shown in place of a missing reading.
What this number is
Water elevation is the height of the lake surface above sea level, as surveyed at Sam Rayburn Reservoir near Jasper, TX. It is the number reservoir operators publish, and it is comparable from one reading to the next at this lake. It is not the depth of the water.
- Measured as
- Water elevation, ft above sea level
- Most recent reading on file
- 155.29 ft · August 29, 2026
- Water quality
- Readings on the lake page
The Corps of Engineers reads Sam Rayburn Reservoir at 154.32 ft, 10.08 ft below its Top of Conservation of 164.40 ft.
Both numbers come from the U.S. Army Corps of Engineers for its Sam Rayburn Reservoir project, on that project's own vertical datum (NGVD-29). That figure is a fixed level rather than a seasonal target, so a reservoir drawn down on purpose in autumn can sit well under it and still be exactly where the Corps intends. Because the datum is the project's own, this elevation is comparable to its own reference and to nothing else — not to a gauge reading from another agency, and not to a lake's mapped surface elevation.
Water quality at Sam Rayburn Reservoir
Sam Rayburn Reservoir's readings for total phosphorus, total nitrogen, chlorophyll-a, and turbidity are shown beside the EPA National Lakes Assessment condition classes for its own ecoregion. Clarity averages 3.9 feet of visibility, shown separately.
The gauge measures how much water is in the lake. The nutrient and algae readings measure what is in the water. A rise or a drawdown does not change those readings until the lake is sampled again.
Common questions
What is the water level at Sam Rayburn Reservoir right now?
The most recent reading from the USGS gauge at Sam Rayburn Reservoir near Jasper, TX is a water elevation of 155.29 ft, taken on August 29, 2026. This page reloads that gauge every time it is opened, so the number above is the current one whenever the station is reporting. USGS lake gauges typically post a new value every 15 to 60 minutes.
What does water elevation mean?
Water elevation is the height of the lake surface above sea level, as surveyed at Sam Rayburn Reservoir near Jasper, TX. It is the number reservoir operators publish, and it is comparable from one reading to the next at this lake. It is not the depth of the water.
Is Sam Rayburn Reservoir low?
Sam Rayburn Reservoir stood at 154.32 ft on September 26, 2026, 10.08 ft below its Top of Conservation of 164.40 ft. Both numbers come from the U.S. Army Corps of Engineers for its Sam Rayburn Reservoir project, on that project's own vertical datum (NGVD-29). That figure is a fixed level rather than a seasonal target, so a reservoir drawn down on purpose in autumn can sit well under it and still be exactly where the Corps intends. Because the datum is the project's own, this elevation is comparable to its own reference and to nothing else — not to a gauge reading from another agency, and not to a lake's mapped surface elevation.
Does the water level affect water quality at Sam Rayburn Reservoir?
Sam Rayburn Reservoir has nutrient and algae readings on record from state and federal monitoring. Each lake's nutrient and algae readings — total phosphorus, total nitrogen, chlorophyll-a, and turbidity — are shown beside the EPA National Lakes Assessment 2022 condition class for that lake's own ecoregion, so a reading is compared against the lakes it would naturally resemble. LakeQuality publishes no letter grade. None of that comes from the gauge. A drawdown can concentrate nutrients and a heavy inflow can dilute them, but neither shows up in the readings until the water is sampled again. Treat the two numbers as separate measurements of the same lake.
Where these numbers come from
The level and temperature are U.S. Geological Survey instantaneous values from gauge 08039300, a public feed with no licence restriction. The water-quality readings come from EPA Water Quality Portal samples submitted by Texas Commission on Environmental Quality. For advisories and standards in Texas, TCEQ is the authority — a gauge reading is neither.