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HOME > PAST ISSUE > July-August 2010 > Article Detail

FEATURE ARTICLE

Science After the Volcano Blew

Research near Mount St. Helens proceeded despite bureaucratic hurdles, limited funding and an extremely hazardous environment

Douglas Larson

Big Hopes for a Second Vessel

2010-07LarsonF6.jpgClick to Enlarge ImageThe near sinking of the cabin cruiser in frigid waters prompted me to file a complaint with the Corps. The Corps authorized the use of its river-survey boat, christened Traveler, for lake research at Mount St. Helens, along with the purchase of survival suits to be worn in case someone fell overboard or the boat sank. Wearing the suits gave me and Patrick Cagney, my frequent field assistant, a sense of security, if only a false one: Had we somehow ended up in the lake, bobbing around in frigid water, the suits would have delayed hypothermia, but floating logs would likely have crushed us.

Hailed as a steel-hulled vessel, the 8-meter-long Traveler was airlifted into Spirit Lake by a U.S. Army twin-rotor Chinook helicopter based at Fort Lewis, Washington. The underside of the boat’s hull had been retrofitted with a cage-like apparatus that enclosed the rudder and propeller assembly. On paper anyway, this jerry-built device was supposed to protect the boat from being immobilized by floating logs and other debris hazards. Nevertheless, despite our cautious operation procedures, collisions with submerged logs were inevitable. Moreover, unforeseeable and sudden shifts in wind direction and velocity often drove logs en masse toward the boat while it was anchored at a lake sampling station. Most of these wind-propelled logs bypassed the boat, but some struck the hull. Frequently, the boat was rammed through log rafts for distances ranging from a few hundred meters to a kilometer or two to reach sampling stations or to return to the boat’s moorage at day’s end.

We made a disturbing discovery in October 1983: Despite its acclaimed steel hull, Traveler was leaking. In the time between field trips to Spirit Lake, usually a period of one to two weeks, the leaks were sufficient to produce a half-meter-deep pool of water in the bottom of the hull. Weighted down by this water, Traveler settled into mud at its moorage. Raising the craft required those aboard to use the boat’s bilge pumps for at least 30 minutes before getting underway.

As with all of our endeavors at Spirit Lake, hope sprang eternal that we could carry on despite such challenges. Optimism was not enough, however. During a field trip on October 28, 1983, the leaks—combined with bureaucratic red tape and copious paperwork—nearly led to a disaster. Shoving off that day, I was accompanied by two upper-management engineers from the Corps’ North Pacific Division in Portland. Aboard to inspect my lake-research program, both men were looking forward to a pleasant day on the lake.

Shortly after reaching a sampling station around 10 a.m., the wind shifted and began to push the log raft in our direction. Soon, the boat was surrounded by logs and was taking on water. I activated the bilge pumps, but they worked for only a short time. One of my passengers discovered that the batteries that powered the pumps were dead. Hemmed in by logs, with the water filling the boat’s hull and no life raft, we found ourselves trapped on a sinking craft.

Using the boat’s radio, I contacted a Corps employee at the Spirit Lake pumping station and informed him of our predicament. I asked if he could send his helicopter to Longview, Washington, a half-hour flight away, to obtain new batteries. He replied yes but said he would first need permission from his supervisor in Portland. I told him to hurry; Our boat was sinking. About an hour later, he radioed back to say he had permission to send the helicopter but that I would need a typed purchase order signed by my immediate supervisor in Portland. Recalling the glacial speed that purchase orders usually progressed through the bureaucracy, I replied that the urgency of our situation called for a more expedient process. Finally the purchasing department authorized an emergency purchase order that was telephoned to a battery dealer in Longview. The batteries reached us around 4 p.m.

Two weeks later, again while encircled by logs, Traveler began to take on more water than usual, causing the boat to settle by the stern. Lake depth at this location was about 30 meters, sufficiently deep to make salvage extremely difficult, if not impossible. Lake-water temperature was 8 degrees Celsius, cold enough to induce hypothermia had I been forced to abandon ship. The bilge pumps evacuated some of the water bubbling up from the engine room’s deck, but water seemed to be coming in faster than ever before. I radioed the helicopter and informed the pilot of the problem. He immediately flew to my position and hovered nearby, waiting to rescue me if the boat capsized or sank. Reassured by my overhead escort, I broke through a kilometer-wide raft of logs before reaching open water. The rest of the journey became a race to reach the moorage before Traveler sank. With Traveler listing to one side, and the throttle wide open, the boat plowed into the lake bottom a few meters from shore. I waded to dry land.

The protective cage was no match for Spirit Lake. An inspection revealed that water had entered the boat through holes that had been drilled in the hull to attach the cage. Repeated blows from submerged and floating logs had loosened the cage’s bolts, breaking their watertight seals. In April 1984, Traveler was unceremoniously hauled back to Portland and retired from service, its “indestructible” designation left in doubt.




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