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Floodplains are Mosaics of Flows, Land Forms, Vegetation, and Critters. Flow: about 65,000 cfs 4 January 2006. Floodplain/ Roughness Mosaic. Channel Meander. Cottonwood. Willow. Valley Oak. Photo by: David Bogener. Photo By: David Bogener. “ The Impenetrable Riparian Jungle ”.
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Floodplains are Mosaics of Flows, Land Forms, Vegetation, and Critters
Flow: about 65,000 cfs 4 January 2006 Floodplain/ Roughness Mosaic
Cottonwood Willow Valley Oak
Photo by: David Bogener Photo By: David Bogener
Plant Mosaic on Floodplain Lower Stanislaus River
Flood Adaptations Large Flume at J. Amorocho Hydraulics Lab – UC Davis
Hydraulic Characteristics of Floodplain Adapted Plants
Swim Response to Sandbar Willow ○ = TBF Swim Chamber ● = MO2 ■ =TBF Flume (3.0 ft/s) (1.5 ft/s) (0.5 ft/s)
Vegetation Planting Patterns NVCS Classification CFG – CA grasses RWS – Riparian wash/scrub RWF – Woodland, no understory RWF – Woodland, dense understory Rip-rap “Goose Down” River
5-Yr Event – 139,600 cfs - Velocities “Goose Down” River
200-Yr Event – 393,300 cfs - Velocities “Goose Down” River
200-Yr Event Velocities “Goose Down” River
200-Yr Event Surface Elevation 20.35 20.38 20.43 20.44 20.44 20.48 “Goose Down” River
Conclusion • Floodplains are mosaics of flows, landscape, plants and animals • Designing floodways should account for and blend all the mosaics • Good designs accommodate our needs, bad designs exacerbate problems • Flood models can help achieve a well crafted system, where plants reduce risk for people and critters and provide ecosystem benefits