CHICAGO (CBS) – The Red Bull Flugtag, the annual festival in which hand-made gliders plummet into Lake Michigan, is in jeopardy.

CBS 2’s Ed Curran explains.

You never really think about the Lake Michigan water levels taking a dive until you need to dive.

In the annual Flugtag, dozens of daring divers in their handcrafted devices take a flying leap off a platform 30 feet in the sky.

For safe diving, the city wants 10 feet of water. But the runway at North Avenue has just 8 feet of water this year, and that’s a concern.

Lake Michigan, overall, is 10 inches lower than last year and 2 feet below the average level for September. In fact, we’re just 6 inches away from the record low for September, set in 1964.

Contributing to the trend have been mild winters that don’t freeze the lake over, allowing more evaporation. Add to that widespread drought, an extremely hot summer, and you are taking water out of the lake faster than you can put it back in.

The good news is, there’s more sandy beach to enjoy.

Operators of the gliders may have to use auto-pilot. For now, all systems are go for full Flugtag flights departing North Avenue at 1 p.m. Saturday.

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