Marker Logo HMdb.org THE HISTORICAL
MARKER DATABASE
“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
San Antonio in Bexar County, Texas — The American South (West South Central)
 

Flooding & Dams

 
 
Flooding & Dams Marker image. Click for full size.
By Cosmos Mariner, May 21, 2018
1. Flooding & Dams Marker
Inscription.
The San Antonio River and surrounding creeks have experienced devastating floods throughout the city's history. Major flooding in 1819, 1868, 1913, and 1921 caused extensive property damage and loss of life. An engineering study after the 1868 flood recommended construction of a dam in the San Antonio River basin north of the city. Over fifty years passed before this structure was completed and a flood bypass channel was built to protect the downtown area.

Vegetation removal, channel straightening, and small dams were also used to control flooding on the river and creeks. In the 1990s deep underground tunnels were built to carry floodwaters from the San Antonio River and San Pedro Creek past the downtown area. At this site the gate to the right of the locks controls the river's upper pool level, as well as river flow in times of flooding. This type of dam is called a crest gate dam.
 
Location. 29° 26.008′ N, 98° 29.072′ W. Marker is in San Antonio, Texas, in Bexar County. Marker can be reached from Brooklyn Avenue north of Avenue B, on the right when traveling north. Touch for map. Marker is located on the San Antonio River Walk, overlooking the Brooklyn Avenue Locks. Marker can be accessed via a short walk from the 709 Avenue B
Marker detail: Flood of September 9-10, 1921 image. Click for full size.
Courtesy San Antonio River Authority
2. Marker detail: Flood of September 9-10, 1921
The flood of September 9-10, 1921, killed fifty-one people and caused extensive damage. Soldiers kept order downtown where streets and buildings were filled with water and debris.
Parking lot. Marker is at or near this postal address: 709 Avenue B, San Antonio TX 78215, United States of America.
 
Other nearby markers. At least 8 other markers are within walking distance of this marker. Locks & Dams (within shouting distance of this marker); The River in the 1800's (approx. ¼ mile away); River Communities (approx. ¼ mile away); The River in the 1900s (approx. ¼ mile away); The San Antonio River (approx. ¼ mile away); Missions in the San Antonio River Valley (approx. ¼ mile away); Mayor Maury Maverick Mural (approx. ¼ mile away); The Hugman Dam (approx. ¼ mile away). Touch for a list and map of all markers in San Antonio.
 
Also see . . .
1. Flash flood hits San Antonio (1921). The San Antonio River winds through southwest Texas, an area that is generally dry. However, on September 7, 1921, a storm stalled over the town of Taylor and dumped an astounding 23.11 inches of rain on the area in less than a day. The immense amount of rain quickly overwhelmed the river. Taylor is located 30 miles upstream from San Antonio, so the resulting flash flood went barreling toward the city. Most of the victims were trapped in their cars by the surprise flood and drowned. Five to 10 feet of water submerged the city’s streets, delaying an evacuation. (Submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida.)
Marker detail: Olmos Creek Dam image. Click for full size.
Courtesy Maverick Publishing Co. San Antonio, May 21, 2018
3. Marker detail: Olmos Creek Dam
A large dam across Olmos Creek, one of the San Antonio River's major tributaries, was completed five years after the devastating 1921 flood. Floodwaters are held behind the dam in the Olmos retention basin and then released slowly downstream. The dam was redesigned and strengthened in 1979.
 

2. San Antonio Flood Management. Flooding has plagued the San Antonio River Basin for generations. As recent as 2015, this region has experienced major flooding. Its effects, flooding in the Upper San Antonio River watershed, are typically felt throughout Bexar, Wilson, Karnes and Goliad counties. (Submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida.) 

3. The People's Waterway. Throughout the 1700s, development of what is now the City of San Antonio occurred alongside five Spanish Colonial missions established near the river. The river was, and continues to be, vital to the community, and it has long been engineered to meet human needs. Acequias, a series of dams and canals, brought river water to the missions and are some of the earliest recorded engineered water systems in the nation. (Submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida.) 

4. Olmos Dam: How it Works. The 75-year-old dam keeps up to 5.1 billion gallons of water from rushing through downtown when rainfall overwhelms the Olmos Creek watershed. Rainfall in the watershed below the dam runs into the San Antonio River. Before reaching downtown, floodwaters are diverted to the river through a tunnel. (Submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida.) 

5. San Antonio Flood Tunnel: How it Works
Marker detail: 1930 bypass channel image. Click for full size.
Courtesy Freese & Nichols, Inc., Fort Worth, May 21, 2018
4. Marker detail: 1930 bypass channel
A concrete bypass channel was completed in 1930 to carry floodwaters in a straight course past the downtown river bend. Today, tourist and maintenance barges use the channel when the river is at normal levels.
. A 24-foot wide tunnel runs deep under downtown San Antonio, bored over a span of more than 10 years and finished in 1996. The tunnel operates as a flood-control canal, catching water from an overflowing San Antonio River before the floods reach downtown and carrying the water safely under the city. (Submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida.) 
 
Categories. DisastersMan-Made FeaturesWaterways & Vessels
 
Marker detail: Shops of Aragon and Romula image. Click for full size.
Courtesy San Antonio Conservation Society Foundation
5. Marker detail: Shops of Aragon and Romula
Robert Hugtnan's 1929 presentation drawing for the San Antonio River plan he called the "Shops of Aragon and Romula" illustrated both the Great Bend and the straight, manmade flood bypass channel.
Flooding & Dams Marker (<i>wide view; Brooklyn Avenue Lock & San Antonio River in background</i>) image. Click for full size.
By Cosmos Mariner, May 21, 2018
6. Flooding & Dams Marker (wide view; Brooklyn Avenue Lock & San Antonio River in background)
Brooklyn Avenue Lock & Dam (<i>wide view</i>) image. Click for full size.
By Cosmos Mariner, May 21, 2018
7. Brooklyn Avenue Lock & Dam (wide view)
 
 
Credits. This page was last revised on July 3, 2018. This page originally submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida. This page has been viewed 28 times since then. Photos:   1, 2, 3, 4, 5, 6. submitted on June 20, 2018, by Cosmos Mariner of Cape Canaveral, Florida.   7. submitted on June 27, 2018, by Cosmos Mariner of Cape Canaveral, Florida. • Andrew Ruppenstein was the editor who published this page.
Paid Advertisement