The Buchanan Dam plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
Partly cloudy
Showers likely
Mostly cloudy
Mostly sunny; warmer
Mostly cloudy
Partly cloudy
Partly cloudy
19° on Nov. 14, 2018, the coldest reading for this week of the year since 1893. Next is 22° in 1920.
Buchanan Dam’s center stands about 1,060 ft above sea level. Within three miles the land runs from 990 ft to 1,140 ft, a difference of 150 ft: gently rolling country. The highest named summit within 15 miles is Dancer Peak, about 1,710 ft, 14 miles southwest.
Under the town center the state geologic map shows Town Mountain Granite, from the Proterozoic, 542 to 2,500 million years old.
The section below crosses 6 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 26×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dolostone. Age: Cambrian, 487 to 497 million years old. About 7 mi of the line.
Granite. Age: Proterozoic, 542 to 2,500 million years old. About 6 mi of the line.
Limestone, dolostone. Age: Cambrian to Early Ordovician, 471 to 497 million years old. About 4 mi of the line.
Paragneiss. Age: Proterozoic, 542 to 2,500 million years old. About 3 mi of the line.
Dolostone, limestone. Age: Early Ordovician, 471 to 487 million years old. About 0.6 mi of the line.
Limestone. Age: Cambrian, 487 to 497 million years old. About 0.3 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in Buchanan Dam reaches the Gulf of America by way of Buchanan Lake and the Colorado: about 410 river miles.
Lakes on the way: Buchanan Lake, Lake Marble Falls and Lake Lyndon B Johnson.
320 miles of the trip are on the Colorado.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Buchanan Dam; river miles along the main stem, rounded.
Buchanan Dam has a humid subtropical climate. Summer afternoons average 95° in August; winter nights fall to about 34° in January. About 32 inches of rain fall in a normal year.
On November 14 Buchanan Dam normally reaches 68° and falls to 45°. The record high is 88°, in 1903; the record low 19°, in 2018. The most rain on this date, 1.53 in, fell in 1954.
Normals 1991–2020 and records since 1893 at Burnet, 14 miles east-southeast, 220 ft higher. NOAA, through RCC-ACIS.
