Whipped Cream Difficulties

Today’s videos go out to FotB Andrew, because.

“The Original Mackinac Bridge Story”, about the history and construction of the bridge.

Opened in 1957, the 26,372-foot-long (4.995 mi; 8.038 km) bridge (familiarly known as “Big Mac” and “Mighty Mac”) is the world’s 24th-longest main span and the longest suspension bridge between anchorages in the Western Hemisphere.

Bonus #1: because one bridge documentary isn’t enough. “Building the Mighty Mac”. This one is a little better quality, I believe.

To the best of my recollection, I have never been on the Mackinac Bridge. I wouldn’t mind making that drive someday, but the last time I was in Michigan, I wasn’t anywhere near the bridge.

Bonus #2: “Challenge at Glen Canyon”. Back in 1983, the Glen Canyon Dam had a problem. There’d been a heavier than expected snowfall that winter, which in turn led to more runoff as the snow melted. This in turn required the dam operators to open the spillways.

At the beginning of June, dam operators opened the gates on the left spillway, sending 10,000 cubic feet per second (280 m3/s), less than one-tenth of capacity, down the tunnel into the river below. After a few days, the entire dam suddenly began to shake violently. The spillway was closed down for inspections and workers discovered that the flow of water was causing cavitation – the explosive collapse of vacuum pockets in water moving at high speed – which was damaging the concrete lining and eroding the rock spillway tunnels from the upper ends of the diversion tunnels, which connect to the bottom of the reservoir. This was rapidly being destroyed by the cavitation and it was feared that a connection would be made to the bottom of Lake Powell, compromising the dam’s foundation and causing the dam to fail.

While some people might have enjoyed seeing the dam fail, it would have caused a lot of problems downstream. So the U.S. Bureau of Reclamation had to fix the spillway issue. But how?