Known Geologic Events at Mount Rainier
The purpose of this page is to list all known, dated gelogic events at Mount Rainier, including lahars, debris flows, large rockfalls, large avalanches, rockfalls, and other events. This list is currently being compiled, so if you find errors or a missing event, please
let Scott know.
Database ID#: 11
Date: Thursday, August 13, 2015
Location: South Tahoma Glacier
Glacier Name: South Tahoma Glacier
Drainage Basin: Tahoma Creek
Event Type: Debris Flow
Weather:
Warm and Dry
Season: Dry
Notes:
On August 13, 2015, during a warm, dry day, four separate debris flow sequences were identified via the Emerald Ridge seismic station. These debris flows began as outburst floods from the South Tahoma Glacier, and quickly "bulked up" in pro-glacial sediment downslope of the glacier terminus. The event was extremely well documented by seismic and acoustic monitors, park staff and visitors, satellite stereo-pair imagery, and by stream gages outside of the park. An acoustic soundscape monitor placed near the Tahoma Creek Trailhead on the West Side Road accurately recorded river noise during the event, including the passage of each debris flow surge. A park visitor also videoed the passage of the third debris flow with his cellphone, literally meters away from the group.
A geomorphic investigation of the area via helicopter on August 13 showed the source of the event at the 2,070 m (6,800 ft) terminus of the South Tahoma Glacier. The outlet stream from the glacier shifted approximately 150 m (500 ft) to the South, incising into pro-glacial sediment. Peak flow velocities were recorded by measuring super-elevation of debris on intact trees in the lower reaches of the debris flow deposits and indicated flows of between 4-6 m/s (14-20 ft/s). Throughout the remainder of August 13 and for the next few days, stream flows remained high on Tahoma Creek.
*** Interesting to note: Glacier Peak also had a debris flow on August 13, 2015 (Fordham and Pfeiffer, 2021 -
https://www.morageology.com/view_pub.php?id=419 ) ***
Estimated Velocity: 4-6 m/s (14-20 ft/s) at lower end
Estimated Peak Flow:
Estimated Volume:
References:
Beason et al., 2019
Beason et al., 2021
Data references:
Beason, S.R., 2012, Small glacial outburst flood occurs on Mount Rainier - October 27, 2012: Unpublished National Park Service Science Brief, 3 p.
Beason, S.R., et al., in prep, Glacial outburst floods and debris flows from the South Tahoma Glacier, Mount Rainier National Park, Washington: August and September, 2015: National Park Service Natural Resource Report NPS/MORA/NRR-2015/XXX.
Copeland, E.A., 2010, Recent periglacial debris flows from Mount Rainier, Washington: M.S. Thesis, Oregon State University, 125 p.
Copeland, E.A., P.M. Kennard, A.W. Nolin, S.T. Lanscaster and G.E. Grant, 2008, Initiation of recent debris flows on Mount Rainier, Washington: A climate warming signal? American Geophysical Union Fall Meeting, San Francisco, CA.
Crandell, D.R., 1971, Postglacial lahars from Mt. Rainier volcano, Washington: U.S. Geological Survey Professional Paper 677, 75 p.
Donovan, K.H.M, 2005, An investigation into the 2003 Van Trump Creek debris flow, Mt. Rainier, Washington, United States of America: BSc Geological Hazards Thesis, University of Portsmouth (UK), 58 p.
Driedger, C.L. and A.G. Fountain, 1989, Glacier outburst floods at Mout Rainier, Washington State, USA: Anals of Glaciology, Vol. 13, 5 p.
Hodge, S., 1972, The movement and basal conditions of the Nisqually Glacier, Mount Rainier: Ph.D Thesis, Univeristy of Washington, xxx p.
Legg, N.T., 2013, Debris flows in glaciated catchments: A case study on Mount Rainier, Washington: M.S. Thesis, Oregon State University, 162 p.
Legg, N.T., A.J. Meigs, G.E. Grant and P.M. Kennard, 2014, Debris flow initiation in proglacial gullies on Mount Rainier, Washington: Geomorphology, Vol. 226, p. 249-260.
Richardson D., 1968, Glacier outburst floods in the Pacific Northwest: U.S. Geological Survey Professional Paper 600-D, D79-D86.
Samora, B., 1991, Chronology of flood events as noted in the superintendent's annual reports 1940-1991, Unpublished Internal Document, Mount Rainier National Park, WA, 13 p.
Scott, K.M., J.W. Vallance, and P.T. Pringle, 1995, Sedimentology, behavior, and hazards of debris flows at Mount Rainier, Washington: United States Geological Survey Professional Paper 1547, 56 p.
Vallance, J.W., C.L. Driedger and W.E. Scott, 2002, Diversion of meltwater from Kautz Glacier initiates small debris flows near Van Trump Park, Mount Rainier, Washington: Washington Geology, Vol. 30, No. 1/2, p. 17-19.
Vallance, J.W., M.L. Cunico and S.P. Schilling, 2003, Debris-flow hazards caused by hydrologic events at Mount Rainier, Washington: United States Geological Survey Open-File Report 2003-368, 4 p.
Walder, J.S. and C.L. Driedger, 1994, Geomorphic changed caused by outburst floods and debris flows at Mount Rainier, Washington, with emphasis on Tahoma Creek valley: U.S. Geological Survey Water-Resources Investigations Report 93-4093, 100 p.
Walder, J.S. and C.L. Driedger, 1994, Rapid geomorphic change caused by glacial outburst floods and debris flows along Tahoma Creek, Mount Rainier, Washington, USA: Arctic and Alpine Research, Vol. 26, No. 4, p. 319-327.
Walder, J.S. and C.L. Driedger, 1995, Frequent outburst floods from South Tahoma Glacier, Mount Rainier, USA: relation to debris flows, meterological origin and implications for subglacial hydrology: Journal of Glaciology, Vol. 41, No. 137, 11 p.