Dire straits! Gridlock Sam tells Brooklyn Paper Radio the BQE is an accident waiting to happen!

Someone is going to have to die on the Brooklyn-Queens Expressway before officials finally fix the collapsing elevated stretch under Brooklyn Heights.

That’s the tragic conclusion of none other than transportation expert — and former city official — Sam Schwartz, who expressed his frustration on Brooklyn Paper Radio on Monday afternoon.

“We thought we had solved this problem back in 2007, then the funding dried up. Now the city has put in a couple of million dollars to, hopefully, act soon before we do have a calamity on the BQE,” Schwartz told hosts Gersh Kuntzman and Vince DiMiceli during a broad-ranging discussion about the highway’s crumbling “triple cantilever” section that runs between Atlantic Avenue and the Brooklyn Bridge.

That portion of the highway was built by Robert Moses in the late 1940s, and was expected to last 50 years. The math, Kuntzman suggested, “means we’re out of time — though I don’t always do basic subtraction properly.”

Schwartz confirmed Kuntzman’s assessment.

“The repairs are long overdue,” he said. Schwartz raised the spectre of death by mentioning many people who have been killed due to infrastructure misadventure, including the victims of the Mianus River Bridge collapse in Connecticut, a death due to a snapped cable on the Brooklyn Bridge, and the Brooklyn dentist who was killed by falling concrete on the FDR drive in Manhattan in 1989.

“There’s your headline, Vince,” Kuntzman, editor emeritus of The Brooklyn Paper, told current boss DiMiceli. “I’ll write it for you, ‘Someone has to die!’ There, I did it.”

“It’s sad, but that does spark action,” Schwartz confirmed.

The transportation expert also discussed his support for a tweaked plan to put tolls on the four East River bridges, part of a larger scheme to reduce some other bridge tolls and dedicate some of the funds for road repair and get DiMiceli to work from Staten Island for just $3 a day — while ensuring the byways and highways he takes become self-sustaining and not dependent on tough-to-get federal dollars.

“We’ll take a quarter of the money and give it to roads and bridges,” he said. “We can’t depend on the feds anymore.”

After Schwartz, DiMiceli and Kuntzman grilled environmentalist Sarah Metz, who is moving forward with her plan to open a packaging-free supermarket called The Fillery. The store looks like it will open later this year in Prospect Heights, she said.

In a broad-ranging discussion, Metz astonished both Kuntzman and DiMiceli with her claim that she produces just one garbage can worth of trash per month. Kuntzman, himself an environmentalist who is producing a show this summer called “Murder at the Food Coop,” questioned how Metz could produce so little trash.

“You do use the toilet, right?” he asked. “Doesn’t that count?”

Metz confirmed that she did use such products as toilet paper, but DiMiceli said soiled material flushed down the loo should not be considered garbage.

DiMiceli claimed, in fact, that toilet contents simply disappear.

Metz pointed out that DiMiceli was wrong.

But hey, that’s Brooklyn Paper Radio — not always right, but never dull.