Thomas Nyhan’s job keeps getting tougher. As executive director of the Central States Southeast and Southwest Areas Pension Fund, Nyhan is responsible for making sure that 454,000 retired Teamster truck drivers receive their monthly pension checks. Last year, Nyhan paid out a whopping $2.7 billion in benefits due to Central States’ retirees and their beneficiaries. The problem is, with only 65,000 active truck drivers contributing to the pension plan and only $19.1 billion in its coffers — down from a high of $26.8 billion in 2007 — it is just a matter of time before the Rosemount, Illinois–based fund executive can no longer write those checks.

“It’s like a tsunami coming off the shore — you can see it,” says Nyhan.

But shrinking assets tell only half the story at Central States. On the other side...