A boulder tumbled down the face of Juneau’s Mount Maria early Wednesday morning, damaging one side of the Basin Road Trestle’s wooden railing. The trestle is closed to all traffic at both ends for public safety.
Pedestrians are still crossing it. But Tom Mattice, the city’s emergency programs manager, encourages people to stay out of the area for their safety.
“After the rain subsides, and the slope starts to drain, we start to gain a little bit of additional stability,” he said. “But that slope will be unstable for quite some time.”
Mattice says slides are more common in the fall, but warm, wet conditions this winter contributed to the rockfall — especially this weekend’s heavy rains.
“We just had enough rain to deteriorate the hillside, to eat away the bond that was holding a rock in place,” he said. “And as you get that melt-and-freeze cycle when it freezes, it expands. And that acts like a jackhammer, pushes the rocks away from the hillside.”
Bridge engineers from the Alaska Department of Transportation visited the site Wednesday to look for signs of deeper structural damage. Their findings will help the City and Bureau of Juneau decide how to proceed with clean-up and repair.
Basin Road will remain closed until further notice.
Correction: An earlier version of this story said the rockfall came from Mount Roberts.
