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ARS Home » Pacific West Area » Tucson, Arizona » SWRC » Research » Publications at this Location » Publication #204392
Title: Impact of Recent Extreme Arizona Storms

Author
item MAGIRL, C. - USGS
item WEBB, R. - USGS
item SCHAFFNER, M. - NWS
item LYON, S. - UNIVERSITY OF ARIZONA
item GRIFFITHS, P. - USGS
item SHOEMAKER, C. - NWS
item Unkrich, Carl
item YATHEENDRADES, S. - UNIVERSITY OF ARIZONA
item TROCH, P. - UNIVERSITY OF ARIZONA
item PYTLAK, E. - NWS
item Goodrich, David - Dave
item DESILETS, S. - UNIVERSITY OF ARIZONA
item YOUBERG, A. - AZ STATE GEOLOGICAL SURV
item PEARTHREE, P. - AZ STATE GEOLOGICAL SURV

Submitted to: Trans American Geophysical Union
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/1/2007
Publication Date: 10/1/2007
Citation: Magirl, C.S., Webb, R.H., Schaffner, M., Lyon, S.W., Griffiths, P.G., Shoemaker, C., Unkrich, C.L., Yatheendrades, S., Troch, P.A., Pytlak, E., Goodrich, D.C., Desilets, S.L., Youberg, A., Pearthree, P.A. 2007. Impact of Recent Extreme Arizona Storms. EOS 88(17): 191-193.

Interpretive Summary: Heavy rainfall on July 27-31, 2006, led to record flooding and an unprecedented outbreak of debris flows in the Santa Catalina Mountains north of Tucson, Arizona. At least 240 hillslope failures spawned debris flows in an area where no more than 10 had been documented historically. More than 18 debris flows destroyed infrastructure in the heavily used Sabino Canyon Recreation Area. In three adjacent canyons, debris flows reached the heads of alluvial fans on the edge of the Tucson metropolitan area. While land-use planners and water-resource managers in southeastern Arizona evaluate the potential of this previously-discounted hazard to development along the mountain front, an interdisciplinary group of scientists has collaborated to better understand this extreme event. The study describes the results of these extreme events and it was also found that a watershed model developed by the ARS was successful in simulating record runoff event with high-quality ground-based rainfall data. However, more research is needed to understand the hazard from debris-flow activity in southeastern Arizona, especially with respect to the frequency of debris-flows and excessive sedimentation, which may compromise flood-control structures designed without accommodation for rapid channel filling.

Technical Abstract: Heavy rainfall on July 27-31, 2006, led to record flooding and an unprecedented outbreak of debris flows in the Santa Catalina Mountains north of Tucson, Arizona. The U.S. Geological Survey (USGS) documented floods of record at six streamflow gages in the Tucson basin, and at least 240 hillslope failures spawned debris flows in an area where no more than 10 had been documented historically. More than 18 debris flows destroyed infrastructure in the heavily used Sabino Canyon Recreation Area (http://wwwpaztcn.wr.usgs.gov/ Santa_Catalina_Debris_Flows.pdf). In three adjacent canyons, debris flows reached the heads of alluvial fans on the edge of the Tucson metropolitan area. While land-use planners and water-resource managers in southeastern Arizona evaluate the potential of this previously-discounted hazard to development along the mountain front, an interdisciplinary group of scientists has collaborated to better understand this extreme event.