The surface pavement for the Big Dig is crumbling about 20 years earlier than expected, according to state officials and reported in the Boston Globe. The repairs could cost $1 million, adding to the Central Artery project’s $22 billion price tag. The work will cause weekend and night lane closures at the tunnel openings where the sloped sections are crumbling.
The cause of the roadway’s decay is apparently a contractor’s decision to use concrete designed for southern climates instead of New England asphalt. The surface concrete is disconnecting from lower layers where the highway slopes, such as at the tunnel ramps. The worst part is the I-93 North section where the tunnel opening meets the Zakim Bridge. This section is expected to be repaired in late June 2012.