The Pension Benefit Guaranty Corp. program that assists multiemployer pension plans has seen its deficit widen significantly. Construction is the largest industry in PBGC's multi-employer program, with 3.9 million people, or 37.4% of the total insured in 2009, the most recent PBGC data published. Multi-employer plans are common in the industry's unionized sector.

On Nov. 16, PBGC reported its multi-employer insurance-plan deficit jumped to $5.2 billion, from $2.8 billion in 2011. PBGC says its assets can meet obligations "for a significant number of years," but it lacks resources to cover longer-term obligations.

The agency also says it is "reasonably possible" multi-employer plans may need $28 billion in future assistance, up from $23 billion in 2011. PBGC direct aid to ailing multi-employer plans dipped last year, to $95 million, from $115 million in 2011.

The Moving Ahead for Progress in the 21st Century Act helped PBGC, allowing multi-employer premiums to rise to $12 per participant in 2013, with inflation-related boosts after that. For 2012 and 2011, the premium was $9.