At 21.5 billion gallons, Wixom Lake is twice as big as Oakland County's largest lake - it emptied in one hour

When mid-Michigan's dams broke, how much water spilled out?

It's hard to contextualize the sheer volume of water that descended on Midland when the dams along the Tittabawassee River broke. Enough to flood the city and force 10,000 residents from their homes. 

Wixom Lake, the man-made reservoir that until Tuesday sat behind the Edenville Dam before it ruptured, had 21.5 billion gallons of water in it. What does that mean when all of it is cascading toward a city of 40,000 people?

To put it in context in terms of the Great Lakes, Lake St. Clair has 903 billion gallons of water in it. Not exactly comparable to Michigan's inland lakes, but that's the largest body of water before the region's five Great Lakes.

As for Metro Detroit's water bodies, Lake Orion has 2.5 billion gallons of water in it. Orchard Lake has 5.9 billion gallons of water in it. Cass Lake, the largest and deepest lake in Oakland County, has 11 billion gallons of water in it - about half of Wixom Lake's water volume. And all of it spilled out in one hour.

Last week, the Tittabawassee River discharged an average amount of water - around 2,000 cubic feet per second. The flow rate oscillated around the average until May 15, when it spiked up to 5,000 cubic feet per second - due to the sizeable 4-7 inches of rain that got dumped on Michigan over the weekend.

RELATED: Wixom Lake in Midland County is virtually empty after two catastrophic dam failures

After a slight decline a day later, the cubic feet of water being discharged rose to 10,000 on May 18. When the dam broke the following day, the discharge rate rose to 60,000 cubic feet of water per second - or 30 times what is normally recorded on the river.

On Wednesday, photos surfaced of what an empty lake with such a sizeable capacity looks like. Docks extended out into nothing as pontoon boats sat with no water to float on.

In a time when Michigan's Great Lakes are supplying its residents with too much water, the sight of an empty lake will offer some cognitive dissonance to Michiganders. Rather than a happy medium, people are left with way too much, or far too little. 

This story has been updated to remove trillions for billions. We regret the mistake.

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