1 / 24

Thomas Jefferson High School Student Water Action Team

Thomas Jefferson High School Student Water Action Team It Rains, it Pours, it Floods!!! Lakes and Dams: Their Uses and Effects By Desirae Luera May 10, 2003 Lakes and Dams A dam is used to impound water by blocking its flow through a watershed

ostinmannual
Download Presentation

Thomas Jefferson High School Student Water Action Team

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Thomas Jefferson High School Student Water Action Team

  2. It Rains, it Pours, it Floods!!! Lakes and Dams: Their Uses and Effects By Desirae Luera May 10, 2003

  3. Lakes and Dams • A dam is used to impound water by blocking its flow through a watershed • Lakes impound water out of basins such as rivers, rain, and melting snow • Many lakes are used as a municipal water resource • Some lakes are used as water supplies for irrigation, electric power, recreation and more

  4. Benefits of Lake Ecosystems • Water provides for diversified vertebrate and invertebrate inhabitants • Water provides habitat for land birds and water fowl • Water released from a dam lets fish and other wildlife animals live in the stream below • Aquatic plants provide food and habitat for diversified creatures • Lakes provide a recreational area for human use

  5. Types of dams • Buttress Dams • Roller Dams • Embankment or Rock-fill Dams • Concrete Dams • Gravity Dams • Arch Dams

  6. Early History • The earliest dams were built in North America providing water for gristmills and saw mills and other manufacturing productions • Dams brought electric service to remote areas and water to arid regions • Dams historically provided water for irrigation and human use and were sometimes located far from the city • Dams were also used for recreation and the tourist industry • Dams were used to abate flooding in rural and urban areas

  7. Manufacturing Processes • Dams with the water impounded were used to turn water wheels • Dams also were used to turn grinding wheels and in the manufacture of grain flower • Dams also were used to turn saw mill blades creating a source of power for the logging industry

  8. Electric Power • Some lakes are created as storage reservoirs for generating electric power • Hydroelectric power plants make use of force of water to make it possible • Stored water flows through hydraulic turbines for electric power,and water generation

  9. Irrigation Uses • Farmers used dams and force water into fields of crops • Farmers shared water from dams with surrounding ranches to water their livestock • Farmers used pumps to force water into an overhead system of water sprinklers • Farmers used stock ponds to release water into streams allowing other wildlife to grow

  10. Recreation and Tourist Industry Benefits • Motor boats and sail boats are used for recreation • Increased water flow from dams to rivers below is used for tourist activities downstream • Reservoirs generate millions of dollars in local recreational economy • Hotels are built near to house visitors and tourist

  11. Dams Used for Flood Control • Early dams used to impound water during heavy rains so that irrigated fields were not washed out • In the Urban areas, dams were used to catch water flow from streets, paved areas and parking lots • Early dams were used to impound water during floods and maintain it for future use

  12. Olmos Dam: San Antonio’s Guardian Protecting San Antonio since 1926 to the present from flooding

  13. Flood History of San Antonio • Historical records showed that the floods of 1724, 1819, 1865, 1899, 1913, and 1921 were particularly destructive.  • In 1865 the removal of in-channel dams and the enlargement bridges increased the potential of flood damage in the downtown area • In 1911 a diversion channel was created to carry storm water away from the downtown horseshoe bend • In 1920 an engineering study on flood prevention to the City of San Antonio was done

  14. 1921 Flooding

  15. Flood of 1921 • Sept. 9 1921, Alazan and Apache Creeks and the San Antonio River flooded due to a 6.8 in. rain. • 50 people died, 14 others were missing and 2000 were given aid by the Red Cross • Flood damage and devastation caused renewed calls for flood control dams at Olmos Creek and in the Woodlawn Area. EARLY SAN ANTONIO RIVER

  16. Olmos Dam in 1926

  17. Arial View of San Antonio Olmos Dam catches all the storm water runoff from the area north of the dam.

  18. Building of Olmos Dam • Olmos Dam was the first major step in flood control. It was built in 1926 and then rebuilt in 1980. • In 1929, the flood loop, Great Bend, was isolated and completed in 1941.

  19. About Olmos Dam • Owner - city of San Antonio • Location - Olmos Creek • Drained area - 32 sq. mi. • Type - concrete • Length - 1,941 ft. • height - 60 ft. • Top width - 12 ft. • Roadway width - 24 ft.

  20. Average Rainfall of the Two Floods in San Antonio • During the 1921 Flood there was 6.83 inches of rain • During the 1998 Flood, there was 11.26 inches of rain. • Due to such flood control, there was less flood damage in the downtown area but the Olmos Park area was flooded.

  21. Flood of ‘98

  22. LAKES AND DAMS • There are many reasons to build reservoir; • For irrigation • Economics • Recreation • Tourism • Flood control

  23. WE NEED REMEMBER: AS WATER FLOWS OVER OUR HANDS, MAY WE USE THEM SKILLFULLY TO PRESERVE OUR PRECIOUS PLANET.

  24. PROJECT BYDESARAE LUERASWAT 2003THOMAS JEFFERSON HIGHMrs. A. Aguirre, SponsorMay 10, 2003

More Related