Lake Travis water level chart
By Mike, independent developer behind zovo.one. Data checked Sep 21, 2026.
Lake Travis stood at 675.60 ft msl on September 21, 2026 in the Texas Water Development Board daily file, 5.4 ft below LCRA's full mark of 681 ft, and 63.8 percent of the way from LCRA's historic low to its historic high.
The daily series, every row in the file, drawn in your browser. Pick a span. Move across the line to read a date and its elevation.
Where today sits in 86 years of readings
The latest row in the TWDB file is 675.60 ft msl on September 21, 2026. Of the 30,665 rows going back to September 30, 1940, 19,149 are lower. Put the other way, the lake has been at or above today's level on 11,516 recorded days.
The phrase since the reservoir first filled needs a boundary. This page uses 1942-01-01, the impoundment date TWDB lists for Lake Travis on its reservoir page, and LCRA dates the completion of Mansfield Dam to 1942. The file's first rows in late 1940 sit far below anything the operated lake has seen, at 548.20 ft on October 31, 1940. Those rows describe a reservoir filling for the first time, not one being operated, so the whole-file minimum is not the drought record. The drought record is the lowest reading on or after the cutoff, 614.18 ft on August 14, 1951.
For 09-21 specifically, the file carries 84 years of readings and today's ranks 71 lowest among them. The lowest reading on this date is 618.20 ft, in 1964, and today sits 57.4 ft above it.
Where the line sits against the LCRA landmarks
The four dashed lines on the chart are published LCRA elevations, not chosen ones. Full at 681 ft msl is what LCRA calls full for water supply purposes, and at that level LCRA puts the lake's contents at 1,115,076 acre-feet. Above it is the flood pool, which LCRA says is designed to hold an additional 776,062 acre-feet of floodwater; Travis is the only lake in the Highland Lakes chain built specifically to hold back floods. The overflow spillway of Mansfield Dam is at 714 ft msl and the top of the dam at 750 ft msl. LCRA's historic high is 710.44 ft on December 25, 1991 and its historic low 614.18 ft on August 14, 1951.
Reading the line against those marks is what a bare chart skips. A Travis reading above 681 ft is water held in the flood pool for controlled release, not a lake in trouble, and a reading well under it is a water supply question rather than a navigation one. The percentage in the table above puts today on a scale from zero at LCRA's historic low to one hundred at its historic high, which is an elevation distance, not a storage volume.
The LCRA record book as the cross-check
LCRA publishes its own ranked lists of the highest and lowest Lake Travis levels, based on daily readings at 8 a.m. The TWDB file is a daily series from the same operator's gauge, so the two should agree, and the build checks that they do rather than assuming it. The lowest reading in the TWDB file since the cutoff, 614.18 ft on August 14, 1951, matches LCRA's historic low exactly, to the hundredth of a foot and to the day. The highest reading in the file is 710.31 ft on December 26, 1991, which is 0.13 ft below LCRA's historic high of 710.44 ft on December 25, 1991. A crest that passes overnight can land on different calendar days and at different heights in an 8 a.m. reading and a daily file, which is why LCRA's figure is the one drawn on the chart and the TWDB figure is reported beside it rather than in its place.
Both tables are transcribed from LCRA's dams and lakes page, which states they are based on daily readings at 8 a.m. Today's reading of 675.60 ft is 34.8 ft below the top of the first table and 61.4 ft above the top of the second.
Check any elevation or date against the record
Enter an elevation in feet msl, a level you remember from a dock post or a past trip, and get where it sits against LCRA's full mark, the spillway and the two historic extremes, plus how many rows in the TWDB file are lower. Or pick a date and get the reading the file holds for that day and its rank. Both answers are computed in your browser from the same series the chart draws. Nothing is sent anywhere.
At 675.60 ft the lake sits 5.4 ft below full, 38.4 ft below the spillway, 61.4 ft above LCRA's historic low, and 63.8 percent of the way through the historic range.
What the level means for getting on the water
At 675.60 ft msl the lake is 5.4 ft below LCRA's full mark. LCRA publishes which public ramps on the Highland Lakes are open and the minimum lake level each one needs, so the honest way to use this page is to compare today's elevation with the minimum listed for the ramp you plan to use on LCRA's boat ramp information page, and to treat that page as the answer rather than this one. A high reading is not a green light either; during floods the operator can close the lake to recreational boating. Ramp status is never restated here, only linked.
Levels are point-in-time readings and can lag real conditions, confirm ramp and hazard status with the lake operator before heading out
Questions about the Lake Travis record
How far back does this chart go?
To September 30, 1940, the first row in the TWDB file for Lake Travis. The file carries 30,665 rows through September 21, 2026, month-end rows in the earliest years and daily rows after that.
Is this the lowest Lake Travis has ever been?
No. LCRA's historic low is 614.18 ft on August 14, 1951, and the lowest reading in the file since the reservoir first filled is 614.18 ft on August 14, 1951. Today sits 61.4 ft above LCRA's mark.
What was the highest?
LCRA's historic high is 710.44 ft on December 25, 1991. The highest row in the TWDB file is 710.31 ft on December 26, 1991, which is 29.31 ft above the 681 ft full mark and still under the 714 ft spillway.
What does full mean at Lake Travis?
LCRA lists the lake as full for water supply purposes at 681 ft msl. That is the top of the water supply pool, not the top of the dam. The flood pool above it is designed space, and the lake has been above 681 ft many times in the record without reaching the spillway.
Why does this chart differ from the live reading elsewhere on the site?
Because they are different series. This chart plots TWDB's daily file. The live reading on the Lake Travis page comes from USGS site 08154500, an instantaneous value which USGS notes is obtained from LCRA. A daily value and an instantaneous one will differ by a tenth of a foot or so on any given day, which is a difference in sampling rather than a disagreement.
How often does it update?
The file is refetched and every figure on this page recomputed on each build, which runs daily.
Where these numbers come from
Every figure on this page is computed in code from one file, the Texas Water Development Board's daily reservoir file for Lake Travis, which TWDB attributes to LCRA's gauge. The build fetches it, looks up the water_level column by name, parses 30,665 rows, rejects a truncated download, and computes the extrema, the counts and the rankings from what is left. None of the numbers is typed by hand and none is carried as a constant that could go stale.
The cross-check is USGS site 08154500, LCRA Lk Travis nr Austin, TX, parameter 00062, elevation of the reservoir water surface above datum in feet. USGS states the data are obtained from LCRA, so this check confirms the file is current and transcribed correctly rather than measuring the lake with a second instrument. On the day this page was first built the two agreed within two hundredths of a foot. TWDB states its Lake Travis values are feet above NAVD88 plus 0.6 ft, USGS lists NAVD88 as the site's datum, and LCRA quotes feet msl. This page labels each series and links it, and makes no claim beyond what each publishes about how those datums relate.
The published landmarks, full, the spillway, the top of the dam, the historic high and the historic low, and both record tables come from LCRA and are constants because they describe the dam and its history, not today's water. I compared the computed extremes from the TWDB file against LCRA's record book before publishing, and the page reports the comparison rather than assuming it.
Want today's reading rather than the record? The Lake Travis water level page carries the live USGS figure and the 24 hour move. The same chart exists for Lake Powell and Lake Mead, both from Reclamation's daily files.
Levels are point-in-time readings and can lag real conditions, confirm ramp and hazard status with the lake operator before heading out. Percent full is current storage divided by published full capacity, not a measure of water quality or safety. Not affiliated with any government agency, data is republished from public USGS, CDEC, and USBR feeds. Some lake-page links are affiliate links that may earn a commission at no extra cost to you, see the disclosure page.