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San Antonio Missions National Historical Park Preservation work on granary frescos
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San Antonio Missions National Historical Park
Hydrologic Activity
Nature and Science

(NPS photo - Kodak DX3900)

New Espada Dam on the San Antonio River

The potential violent power of flood waters of the San Antonio River during heavy or extended rainfall prompted the U.S. Army Corps of Engineers to create a huge, straight river channel almost a half a century ago. Although soils near the mission sites have a great deal of clay content, the soil is relatively shallow over limestone bedrock. There are deep alluvial soils in the former river floodplain; the mission labores were located there. Aggressive hydrologic activity can erode isolated sections of banks of rivers, streams and acequias. Man-made cement retaining walls along the river and streams are testament to this hydrologic activity.

The San Antonio River Authority and the U.S. Army Corps of Engineers, in partnership with other organizations, are restoring 13 miles of the flood control channel to improve recreation and wildlife habitat. The park is actively engaged in this project and has projects to maintain and improve the ecology of park streams. Click on this link to learn more about the river improvement project.

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Longhorn cattle evolved from 3 breeds of cattle that the Spanish imported in the 18th century.

Did You Know?
that Texas longhorn cattle evolved from 3 breeds the Spanish imported to the Americas in the 17th and 18th centuries? They were the barrenda or piebald, the retinto, and ganado prieto. Modern longhorn have long legs and a narrow body - perfectly suited to travel long distances in dry, harsh country.

Last Updated: January 12, 2011 at 10:05 MST