A federal inspection has confirmed that a set of three tunnels along a 190 km railroad spur line between Coos Bay and Eugene, Oregon are dangerous and require “immediate repairs” to allow resumption of service.
A three-page report released on 15th November concluded that rotting timbers in each of the three tunnels “have reached the end of their useful life and can no longer provide adequate support.” The report, prepared by the Office of Safety Assurance and Compliance with the Federal Railroad Administration, warned that even repair work would be hazardous.
“The existing unsafe conditions include ceiling and wall rock fall, rock debris fall, timber set and lagging instability and vertical timber set kick out. Any future inspection or maintenance should be done with great care, with an understanding of the potential hazards,” the report said. “The original timber set design has severe limitations in its ability to resist lateral earth and rock loads. In addition, the timber sets are susceptible to fire.”
The report confirms findings from an inspection by Central Oregon & Pacific Railroad, which operated the spur line before it was shut down without notice in September. The railroad received its report in July but did not notify shippers or state or federal officials until closing the line. The lack of warning and one-day’s notice of the rail line closure has angered shippers and led to a lawsuit by the Oregon International Port of Coos Bay.
Officials from RailAmerica, the railroad’s parent company, said repairs to the line would cost USD23 million. They asked the Oregon Department of Transportation, the Port of Coos Bay, Union Pacific and shippers that use the spur line to help finance the repairs.
The rail tunnels - one near Mapleton and two others near Florence - were originally built in the 1880s and rebuilt around 1914. The main problems discovered during the inspections were the deterioration of untreated cedar timbers, lagging and footing blocks. The problems were more severe in the wetter portions of the tunnels, with the deterioration causing a shifting of the timber supports and periodic loss of the horizontal struts between adjacent sets. When hit with a hammer, the lower sections of the timber set posts sounded “hollow or decayed,” according to the report.
In one of the tunnels, a 655 m underground section near Florence, more than 60 cm of rock sits perched on rotting ceiling timbers. The engineers who inspected the tunnel said the material would fall down from the ceiling in the near future and there was a danger of timber and lagging falling into the tunnel.
In the second tunnel near Florence, there are timber sets that have rotted at their bases and then slid off their footings. They moved two feet from their original position. The sandstone inside the 467 m-long tunnel needs reinforced ceiling and sidewall support, as the tunnel bore faces “have weathered over the years and may be exerting more vertical and lateral pressures than where originally anticipated,” the report said. 49/07.
