Effects of the May 18 mudflows in the vicinity of Mount St. Helens. Cowlitz County, Washington. 1980.

Slide description and index card: Effects of the May 18 mudflows in the vicinity of Mount St. Helens. C, Mudflows destroyed nearly all the bridges that crossed streams draining from the northern, northeastern, and northwestern parts of Mount St. Helens. This lack of stream crossings greatly hampered ground rescue and recovery efforts. The steel highway bridge shown in photo no. 35ct (msh_1249_00035_ct) was formerly at the site shown in this photo, on the North Fork Toutle River 23 miles downstream from headwaters on Mount St. Helens. Aerial view. Cowlitz County, Washington. May 20, 1980. (Photo by Philip Carpenter). Published as Figure 31-C in U.S. Geological Survey. Professional Paper 1949. 1982.