Rivers

Where the water is

How much Lake Travis could rise from the water on its way, and the rivers feeding the Highland Lakes drawn as wide as the water in them.

Lake Travis

How much the lake could rise

The rivers' water, delayed by its trip to the lake, against what Mansfield Dam releases, through the lake's storage curve.

Working out what the rivers would do to the lake…

Llano River near Junction and Llano River near Mason are above action stage

Stages as of Oct 1, 1:41 PM

Heading for Lake Travis

336 cfs

667 acre-feet a day, under an inch a day of lake rise at 674.7 ft

Llano 326Sandy Creek 0Pedernales 10

Heading for Lake Buchanan

66 cfs

131 acre-feet a day on the Colorado near San Saba, which already carries the San Saba River

NWS forecast: the Llano River at Llano crests near 16.1 ft, moderate flooding, Fri 5 AM with about 49,700 cfs. That water joins Lake LBJ at Kingsland.

below action stageaction stageflood stageNWS forecasts itRivers are drawn as wide as the water in them. Select a gauge for its week and forecast; the dams show their floodgate status. Map data from OpenStreetMap.

Llano River near Junction

Above action stage

Joins Lake LBJ at Kingsland

15.66 ft · 25,215 cfs · action 12 ft · flood 16 ft

NWS forecast: crests near 18.2 ft, minor flooding, Thu 7 PM with about 35,600 cfs.

Loading the past week…observedforecast

Gauge page on water.noaa.gov

Every gauge as a table

Gauge	Stage	Action	Flood	Flow	NWS crest
Llano River near JunctionAbove action stage	15.66 ft	12 ft	16 ft	25,215 cfs	18.2 ft
Llano River near MasonAbove action stage	11.75 ft	11 ft	18 ft	5,594 cfs	20.4 ft
Llano River at Llano	2.35 ft	10 ft	10 ft	326 cfs	16.1 ft
Pedernales River near Fredericksburg	7.76 ft	12 ft	22 ft	10 cfs	—
Pedernales River near Johnson City	10.29 ft	13 ft	14 ft	10 cfs	—
Sandy Creek at Hwy 71 near Kingsland	4.77 ft	8 ft	12 ft	0 cfs	9.1 ft
San Saba River at Menard	2.84 ft	8 ft	18 ft	31 cfs	—
San Saba River near Brady	2.34 ft	16 ft	18 ft	35 cfs	—
San Saba River at San Saba	2.91 ft	20 ft	24 ft	56 cfs	—
Colorado River at Winchell	1.19 ft	24 ft	26 ft	0 cfs	—
Colorado River near San Saba	2.10 ft	25 ft	30 ft	66 cfs	—
Colorado River at Austin	13.57 ft	25 ft	33 ft	328 cfs	18.7 ft
Colorado River at Bastrop	3.69 ft	14 ft	23 ft	1,116 cfs	8.6 ft
Colorado River at Smithville	2.09 ft	10 ft	20 ft	902 cfs	5.9 ft
Colorado River above La Grange	3.75 ft	19 ft	26 ft	983 cfs	8.6 ft
Colorado River at Columbus	10.16 ft	30 ft	34 ft	974 cfs	14.4 ft
Colorado River at Wharton	8.26 ft	20 ft	39 ft	495 cfs	14.1 ft
Colorado River at Bay City	3.35 ft	23 ft	44 ft	747 cfs	8.5 ft
Colorado River at Matagorda	2.23 ft	4.8 ft	8.8 ft	—	3.4 ft
Onion Creek at Buda	1.27 ft	8 ft	15 ft	0 cfs	—
Onion Creek at Hwy 183, Austin	4.00 ft	15 ft	17 ft	0 cfs	—

A rising Llano reaches Lake LBJ first and Lake Travis a day or so later; the Pedernales comes straight into Travis. Gauges and stages are LCRA’s and the National Weather Service’s; the lake-rise figures are this site’s arithmetic from the Lake Travis storage curve, before releases and evaporation. Unofficial copy of LCRA’s river levels.