Report cites costs, risks of Big Dig leaks

By the time new highway administrator Frank DePaola briefed the transportation board of directors on the issue this month, he likened the major leaks to the water from “three garden hoses’’ and stressed that “the tunnels are safe.’’

Ernst’s report does not say the tunnels are unsafe, but voices more alarm at the potential risks of the leaks. The report was written after a corroded 110-pound light fixture crashed Feb. 8 in the O’Neill Tunnel, revealing widespread corrosion in lights throughout the 7.5-mile Big Dig tunnel system. Ernst’s report makes it clear that the fallen light is part of a much larger problem: the salty ground water that seeps in through cracks and other openings in the tunnels.

“Tunnel leaks are a more vexing problem as they are widespread throughout the tunnel and are the cause of safety concerns and [have] a damaging effect on the tunnel structure and equipment,’’ wrote Ernst.

Ernst listed more than $150 million in immediate leak repair and prevention projects and stressed that potentially more-costly leak repairs lie ahead, including extensive excavation to repair major cracks in one tunnel. He has previously said that replacing and rewiring corroded tunnel lights could cost $200 million.

In the aftermath of the fallen tunnel light, Mullan first reprimanded and then suspended Ernst for his role in failing to notify the public for more than a month after the light fixture collapsed onto the highway. The suspension was announced on the same day that DePaola reassured the board that the water leaks are not a major problem.

DePaola’s predecessor as highway administrator, Frank Tramontozzi, who was forced to resign in March for his role in mishandling the light fixture collapse, said Ernst’s report is quite accurate.

“Wow, that’s telling it like it is,’’ said Tramontozzi.