About 13,000 years ago, Glacier Peak blew its stack at roughly the same scale as the 1980 eruption at Mount St. Helens. Erupting nine times, the volcano spewed lava and mud along the Skagit and Stillaguamish rivers all the way to Puget Sound, tying Mount St. Helens for the largest in Washington’s history.
Since then, Glacier Peak has erupted at least six more times — most recently about 1700 A.D.
But Glacier Peak has exactly one U.S. Geological Survey remote monitoring station installed in its vicinity. Roughly 20 similar stations are scattered around Mount St. Helens.
Each station is a tiny hut too small for a person to lie down inside — two people could squeeze in if they sit up. Each station consists of a seismometer, a GPS device and a transmitter to beam data back to USGS regional headquarters in Vancouver. The GPS devices track when subterranean activity moves the ground’s surface beneath a station.
“We are looking for signs that magma is working its way toward the surface,” said Seth Moran, scientist-in-charge at the Cascade Volcano Observatory in Vancouver.
Signs include tiny earthquakes; magma creeping upwards to deform the sides of a volcano and sulfur dioxide, carbon dioxide and water vapor wafting out of fumaroles or a peak’s summit. Last September, the USGS sent its first drone over Mount St. Helens to measure gas emissions.
“When a volcano wakes up, there is uncertainty,” Moran said. “What is going to happen, what will be the size of the eruption — it’s about buying society more time to get ready [because] volcanoes can wake up very fast.”
The 1980 Mount St. Helens eruption that killed 57 people went from quiet to dangerously active on a fast timeline, geologically speaking. A 4.2-on-the-Richter-scale earthquake began the process on March 20. Steam started venting on March 27, the mountain’s north side began bulging by the end of April, and a 5.1 earthquake collapsed the north face on May 18, sending plumes of smoke and ash across a dozen Western states and lahars that flattened surrounding forests.
The David A. Johnston Cascades Volcano Observatory (named after a geologist who died in the eruption) was established the summer after the eruptions to both study the threat and provide advance warning. Remote monitoring stations provide data to this central location to help alert emergency services, to warn at-risk populations, and to know whether to prepare for a massive explosion or a less disruptive volcanic burp. Aircraft advisories help planes avoid any dangerous smoke.
Without mapping a potential eruption ahead of time, “it’s almost impossible to catch up [or] to get equipment in place,” Moran said.
Including installation out in the wilderness, each station costs about $100,000. Glacier Peak is the USGS’s top priority to install more monitoring stations, Moran said. Mount Baker — currently with two stations — is close behind.
Congress is slowly tackling that need.
The U.S. House and Senate recently and overwhelmingly passed a package of 110 bills on land and natural resource issues — including allocating a maximum of $55 million for volcano monitoring at the USGS. President Donald Trump signed the package on Tuesday. It’s a relief: A similar volcano bill by U.S. Sen. Maria Cantwell, D-Washington, Sen. Lisa Murkowski, R-Alaska, and Mazie Hirono, D-Hawaii, failed to make it through the 2018 session.
But the volcano legislation in the omnibus bill is just a start. As an authorization bill, it sets the upper limit for what might actually be spent in a follow-up appropriations bill. The authorization bill did not specify how much of the potential $55 million would go to the USGS’s Vancouver office to monitor volcanoes in Washington and Oregon. The Democrat-controlled House and Republican-dominated Senate will pin down the exact amount as they unveil their appropriations bills later in 2019.
The bottom line is that Moran and the USGS Vancouver office have no idea how much money they’ll get from Congress to improve volcano monitoring. Additionally, Moran and other staff members are not allowed to talk specific dollar figures until the appropriations are settled.
What’s clear is more monitoring stations are desperately needed in the Pacific Northwest. Eight of the nation’s 18 most threatening volcanoes are in the Cascades in Washington and Oregon, according to a 2018 USGS report. (The rest are in California, Alaska and Hawaii.) In Washington, these are Glacier Peak, Mount St. Helens, Mount Rainier and Mount Baker. The four in Oregon are Mount Hood, The Three Sisters, Newberry Volcano and Crater Lake. Mount Adams in Washington just missed the list of highest threats.
The Pacific Northwest’s high volcano eruption risk comes from the Juan de Fuca, Gorda and Explorer plates sliding under the North American tectonic plate off the coast of Washington and Oregon. That forces water and other fluids down into the Earth’s mantle, where they mix with hot subterranean rock beneath the Cascades, which then works its way toward the surface as magma.
The USGS ranks volcano threats based on geological makeup, frequency of past eruptions, the size and time since a volcano’s largest eruption, when the last eruptions occurred, lava flow amounts of previous eruptions, and the state of ice and water on the mountain. Other factors include an area’s permanent population, its distance from the volcano, traffic going through the area, manufacturing presence and the proximity of power structures.
Moran said each of Washington and Oregon’s eight highest-threat peaks should have 12 to 20 monitoring stations, which translates to 104 to 160 stations altogether. There are currently 75 stations within 12 miles of the eight peaks; all are operated by the USGS, the University of Washington and other agencies. But not all are fully equipped with both seismometers and GPS devices.
For now, the USGS's Vancouver office can only wait to see how many new monitoring stations it can set up. But for now, the USGS monitoring screens in Vancouver show no rumbles or disturbances.
“The Cascade Mountains are all quiet,” Moran said.