On Sunday May 18, 1980 at 8:32 am, Mount St. Helens erupted. Shaken by an earthquake measuring 5.1, the north face of this tall symmetrical mountain collapsed in a massive avalanche of rock debris. In a few moments, the slab of rock and ice slammed into Spirit Lake, crossed a ridge 1,300 feet high and roared 14 miles down the Toutle River. The avalanche rapidly released pressurized gases within the volcano. A tremendous lateral explosion ripped through the avalanche and developed into a turbulent, stone-filled wind that swept over ridges and toppled trees. Nearly 150 square miles of forest was blown over or left standing but dead. At the same time, a mushroom-shaped column of ash rose thousands of feet skyward and drifted eastward with the prevailing winds, turning day into night as dark, gray ash fell over eastern Washington and beyond. Wet, cement-like slurries of rock and mud scoured all sides of the volcano. Searing flows of pumice poured from the crater. The eruption lasted 9 hours, but Mount St. Helens and the surrounding landscape were dramatically changed within moments.
Inside the Monument, the environment is left to respond naturally to the disturbance. Scientists and visitors have followed the changes in and around the volcano. Surviving plants and animals rise out of the ash, re-colonizing their new environment, as returning birds and animals find a niche in a different forest on the slopes of Mount St. Helens. The volcano continued to erupt until 1986, violently at first, then quietly building a lava dome. Thick pasty lava eruptions oozed out, each one piling on top of the next, like pancakes in a sloppy pile. The lava dome is now 920 feet high.
The United States Geological Survey scientists continue to monitor the volcano for earthquakes, swelling and gas emissions.
Recreation
Special Conditions Closure Information The Forest Service, USGS and law enforcement agencies have refined area and road closures to reflect current and predicted volcanic activity, hazard zones and to balance public safety with recreational access. Mount St. Helens continues to remain in a state of intense unrest and will continue to go through episodic changes in the level of unrest over a period of days, weeks or even months. The attached map identifies the closure area, any roads or trails that are closed outside the main closure area. There is no public access into any portion of the closure area or on any of the listed roads and trails. Closure information will be posted at gated closures and at trailheads leading into the closure area. This information applies only to National Forest and National Volcanic Monument lands.
Camping
Camping is allowed at Climbers Bivouac. It is a developed site with parking and toilets, but no running water, picnic tables, or garbage service. Please pack out all litter. Hike-in camping is allowed below 4,800 feet elevation on the south side of the volcano. Use no-trace practices to reduce impacts. Due to the sensitivity of the upper slopes of the volcano, camping is not encouraged above 4,800 foot elevation. If a high camp is planned, climbers must have permits for each date that they intend to be above 4,800 elevation.
Climbing
Mount St. Helens is a popular climb for both beginning and experienced mountaineers. although people climb Mount St. Helens year-round, late spring through early fall is the most popular season. Most climbers use the Monitor Ridge route from Climbers Bivouac. This route gains 4,500 feet in 5 miles to the crater rim at 8,365 feet elevation.
Although strenuous, the climb is suitable for people in good physical condition who are comfortable scrambling on steep, rugged terrain. Most climbers complete the round trip in 7 to 12 hours. Entry into the crater is strictly prohibited.
All people must have a climbing permit to be above 4,800 feet elevation on Mount St. Helens. Permits are required year-round. Climbers must display their own climbing permit. Permits are valid for 24 hours starting at midnight for the date of climb and are nontransferable. Maximum party size is 12 climbers. From May 15 through October 31, climbing is limited to 100 people per day. From April 1 through October 31, a fee is charged for climbing permits. From November 1 through March 31 there is no quota and no charge for permits.
Hiking
Mount St. Helens National Volcanic Monument has nearly 200 miles of trails where hikers can experience features of the 1980 eruption. Most of these trails can be accessed without a permit or quota.
Recommended hiking trails in the Monument include:
Trails accessed from Forest Roads 81 and 83:
- Ape Canyon #234
- Lava Canyon #184
- Sheep Canyon #240
Trails accessed from Forest Roads 99 and 26:
- Boundary #1
- Independence Pass #227
- Truman #207
Trails accessed from State Route 504:
- Boundary #1
- South Coldwater #230
