Notes

Slide Show

Outline

1	Question of the day: How is a Tucson flood like a redneck divorce?
2	Rainfall in southern Arizona A Case of Famine and Feast
3	Digital Elevation Map
4	Annual Precipitation
5	Anatomy of River Valley
6	Typical flood hazard is water covering the floodplain.
7	Major Drainages of Tucson Basin
8	Flow Gauge Records, Santa Cruz River
9	1983 Santa Cruz River @ Congress
10	Santa Cruz River @ Congress
11	Rillito at First Avenue, Oct. 1983
12	Active river channel moves by bank erosion. This is principle flood hazard in Tucson.
13	Increased frequency of record Santa Cruz flows since 1960. A. Climatic effect? Global warming? Enhanced El Nino? B. Urbanization? Urbanized desert increases runoff by four times compared to undeveloped desert.
14	Effects of Urbanization on Stream Flow
15	Flood Forecasting
16	Flood Control Measures A. Structural Dams Channelization Diversion channels B. Nonstructural Zoning and land-use restrictions Land acquisition programs Flood forecasting Public education
17	Soil cementing, Rillito @ Campbell
18	A: Sooner or later, someone’s going to loose a trailer.
19	Teton Dam on Snake River
20	Beginning of water piping and erosion of earthfill.
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24	Complete failure
25	Permeable volcanic rock in footings of Teton Dam