Photo Information

Ash-covered drainage canal, Philippines
Photograph by W.E. Scott on June 23, 1991

Voclanic ash was removed from this drainage canal at Clark Air Base in the Philippines to permit the free flow of water. The 1980 eruption of Mount St. Helens demonstrated the importance of preventing as much ash as possible from entering storm drainages and sanitary sewers in order to limit ash from invading waste-water treatment facilities. Residents must help in preventing ash from entering the hundreds or thousands of storm sewers, "manhole" covers, and storm-drainage systems in their community, especially during clean-up operations.

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U.S. Department of the Interior, U.S. Geological Survey, Menlo Park, California, USA
Contact: VHP WWW Team
Last modification: 30 November 1999 (SRB)