The Blanco River at Blanco

The Blanco River rises in Kendall County and runs about eighty-seven miles east to the San Marcos River, and this crossing is near the top of it. Most of the time it is a modest, clear stream over limestone ledges, held just downstream in the long pool at Blanco State Park behind a set of small dams that a Civilian Conservation Corps company built in 1933 and 1934 and that are still in use. On Memorial Day weekend in 2015 more than a foot of rain fell overnight on the upper basin, and the river became something else entirely. The name is the Spanish for white, given for the pale limestone in the bed rather than for the water, which runs deep green in the pools. In an ordinary summer the crossing here carries a stream you could wade. Downstream at Wimberley the Blanco rose about five feet every fifteen minutes for an hour. The gauge at the Ranch Road 12 bridge failed at forty feet. The US Geological Survey later reconstructed the crest at 44.9 feet and the peak discharge at roughly 175,000 cubic feet a second, against a previous record of 33.3 feet set in 1929. Thirteen people died. Blanco State Park, upstream, lost dam works and stayed closed for more than two months. The same river is also a losing stream. East of here stretches of its bed lie over the Edwards outcrop and hand their water down into the aquifer instead of carrying it on, so in a dry year the Blanco can be running here at Blanco and be dry gravel at Kyle. It is the same rock producing both extremes.