Effects of coarse woody debris and its removal on a channel affected by the 1980 eruption of Mount St. Helens, Washington

Thomas E. Lisle

doi:10.1029/95wr00734

Treesearch

Effects of coarse woody debris and its removal on a channel affected by the 1980 eruption of Mount St. Helens, Washington

Informally Refereed

Authors:

Thomas E. Lisle

Year:

1995

Type:

Miscellaneous Publication

Station:

Pacific Southwest Research Station

DOI:

https://doi.org/10.1029/95wr00734

Source:

Water Resources Research 31(7): 1797-1808.

Download (PDF 438 KB)

Download (PDF 438 KB): https://research.fs.usda.gov/download/treesearch/7836.pdf

Abstract

Abstract - During the May 18, 1980, eruption of Mount St. Helens, Washington, a pyroclastic surge introduced large volumes of coarse woody debris (CWD) and fine grained sediment to Clearwater Creek, approximately 15 km northeast of the summit. Effects of controlled CWD removal on sediment storage, substrate, and pool frequency and volume were measured in four reaches, each with three 200-m segments, from 1982 to 1990. In each reach the upstream segment served as a control with no debris removal, and CWD was totally and selectively removed from the other two segments. Unique among similar experiments are the large size and volume of CWD and the large inputs of fine grained sediment. Except for segments of two reaches that received debris torrents, the Clearwater channel thalweg scoured until 1985.

Keywords

PSW4351, eruption, Mount St Helens, Washington, coarse woody debris, CWD, fine sediment, Clearwater Creek, sediment storage, pools, geomorphic

Citation

Lisle, Thomas E. 1995. Effects of coarse woody debris and its removal on a channel affected by the 1980 eruption of Mount St. Helens, Washington. Water Resources Research 31(7): 1797-1808.