| River / Basin | Total drainage area (square kilometers) |
Gaged drainage area (square kilometers) |
Stream length (kilometers) |
Channel gradient (range) (meters/meters) |
Valley trend | Area within blast (square kilometers) |
| Toutle River Basin
(includes Green, N.F. Toutle, S.F. Toutle, Toutle Mainstem) |
1322
(includes non-contributing area within North Fork Toutle basin) |
1285
(at Tower Road near Silver Lake, Washington, includes non-contributing area within North Fork Toutle basin) |
-- | -- | -- | 468 |
| Green River | 342 | 334 | 53 | 0.2-0.01 | E-W | 171 |
| North Fork Toutle River - 1981 WY
(includes Green) |
663 | 617 | 52
(excludes Green) |
0.08-0.003 | E-W | 448 |
| North Fork Toutle River - 1982 WY
(includes Green) |
728 | 682 | 63
(excludes Green) |
0.15-0.003 | E-W | 448 |
| North Fork Toutle River - 1983-1985 WY
(includes Green) |
782 | 736 | 63
(excludes Green) |
0.15-0.003 | E-W | 448 |
| South Fork Toutle River | 328 | 303 | 48 | 0.10-0.002 | SE-NW | 20 |
| Toutle River (Mainstem) | -- | -- | 26 | 0.001-0.009 | E-W | -- |
|
Excerpts from:
Meyer, Nolan, and Dodge, 1986, USGS Open-File Report 85-412, and
Meyer and Dodge, 1988, USGS Open-File Report 87-549 |
||||||
Return to:
[Toutle River Drainage Menu] ...
[Mount St. Helens River Drainage Menu] ...
[May 18, 1980 Eruption Menu] ...
