When Valdez Moved: The Good Friday Earthquake
On the type of cloudless day that transforms Valdez into the prettiest place on the planet, two men were sitting on a propane tank enjoying the return of the sun. I interrupted their basking with a question: "Where is Old Valdez?"
"It's over there," the man with baseball cap and sunglasses said. "You're not going to find much."
He was right. The magnitude 9.2 earthquake of March 27, 1964, destroyed the Valdez that was. Only concrete foundations, rusted pretzels of plumbing, and rotten dock pilings remain. The Valdez that exists today is a town rebuilt a few miles west of the original.
The geologic instability of Old Valdez, which was constructed in the flood plain of Valdez Glacier, was noticed in 1899 by Edward Gillete. Gillete was an engineer working with Capt. W.R. Abercrombie, who surveyed the Gold Rush route from Valdez to Copper Center almost a century ago.
"Where the small town of Valdez has been hastily built there is danger at any time of having the buildings swept into the Bay by swift and quickly changing channels formed by the numerous streams flowing from uncertain and everchanging parts of the Valdez Glacier situated some four miles north of town," Gillete wrote.
I found Gillete's warning in a 1966 U.S. Geological Survey paper, "Effects of the Earthquake of March 26, 1964, at Valdez, Alaska." In the paper, written shortly after the earthquake, geologists Henry Coulter and Ralph Migliaccio recommended moving Valdez.
Sitting in the drainage of Valdez Glacier did more than put the town at flood risk, Coulter and Migliaccio wrote. Old Valdez sat on water-saturated silt, fine sand, and gravel. This unstable foundation proved disastrous when the big earthquake hit.
Saturated, fine-grain soils often feel as solid as concrete until violently shaken. In a process called liquefaction, solid ground suddenly acts as a liquid when earthquake movement alters the delicate structure of fine-grained soils that are buttressed by water.
Liquefaction of the underlying soil of the Old Valdez waterfront caused an underwater landslide. The rapid sluffing of 97 million cubic yards of soils under the ocean surface caused a giant wave. The wave, estimated to be at least 30 feet high, slammed into the Valdez waterfront. As the wave bounced off the other side of the bay, Old Valdez was pummeled repeatedly. According to a plaque now standing on a house foundation at the Old Valdez site, 32 people died as a result of the underwater landslide and resulting waves.
"The Valdez waterfront has proven to be unstable under seismic conditions," Coulter and Migliaccio concluded. They recommended the town be rebuilt at the site where it is today. New Town, as some of the 1964 survivors call Valdez today, sits near the mouth of Mineral Creek. The geologists recommended the Mineral Creek site because it sits on bedrock rather than on silty, water-drenched soil.
Earthquake vulnerability probably wasn't on the minds of the traders and gold chasers who "hastily built" Old Valdez in 1898. They were more interested in a quick path to the gold fields of the Klondike, and that path started with a trip up Valdez Glacier.