Impact of Mount St. Helens eruption on hydrology and water quality
The 1980 eruptions of Mount St. Helens in southeast Washington resulted in a pronounced effect on the surface and ground water resources of the state. In response to the volcanic activity, the U.S. Geological Survey intensified statewide surface and ground water sampling programs to determine the nature and magnitude of the volcanic-induced variations. Streams to the east of Mount St. Helens received the major ash fallout. Chemical effects were best noted in smaller streams sampled 60 to 70 miles northeast of Mount St. Helens. The chemical variations observed were pronounced but short lived. Sulfate and chloride increases in anionic composition were prevalent immediately following the eruption however, the original bicarbonate predominance was again attained within several days. Suspended iron and aluminum concentrations were similarly elevated during the period of greatest ash deposition (highest turbidity) however, the dissolved concentrations remained relatively constant. Depressions of pH were minor and short lived. Streams draining to the south, tributaries to the Columbia river, showed little observable changes in water chemistry. Streams draining to the west (Toutle river and its tributaries) were compositionally affected by the various volcanic activities. Chloride and sulfate anion percentage exceeded the bicarbonate percentage up to one month following the eruption period. Streams and lakes sampled in the immediate vicinity of Mount St. Helens, in addition to trace metals, contained organic compounds derived from decomposing wood buried in the debris deposits. This organic material may constitute a significant source of organic compounds to surface and ground water for some time to come.
- Research Organization:
- Geological Survey, Arvada, CO (USA)
- OSTI ID:
- 6378111
- Report Number(s):
- N-8311538
- Country of Publication:
- United States
- Language:
- English
Similar Records
Chemistry of thermal waters and mineralogy of the new deposits at Mount St. Helens: a preliminary report
Mount St. Helens ash fall in the Bull Run watershed, Oregon, May-June 1980
Related Subjects
VOLCANOES
ENVIRONMENTAL EFFECTS
WASHINGTON
WATER POLLUTION
GROUND WATER
HYDROLOGY
RIVERS
STREAMS
WATER QUALITY
ENVIRONMENTAL QUALITY
FEDERAL REGION X
HYDROGEN COMPOUNDS
NORTH AMERICA
OXYGEN COMPOUNDS
POLLUTION
SURFACE WATERS
USA
WATER
520100* - Environment
Aquatic- Basic Studies- (-1989)