Over the weekend, at 7:30 p.m. in the evening, 1 million people in Bulawayo, Zimbabwe, were asked to flush their toilets, at exactly the same time.

It was called the Big Flush.

While this city will probably be setting the world record for simultaneous, synchronized toilet flushing, the actual goal of the event is deadly serious, NPR explains:

After months of severe water shortages, the city’s authorities have imposed 72 hours of water rationing a week. Two of Bulawayo’s five supply dams have dried up because of the drought, according to the online version of Africa Review. So, when water is restored to the city’s 1 million residents today, the city council has asked everyone to pitch in for the “Big Flush,” at 7:30 p.m. local time.

The idea is to clear out the sanitary facilities, which authorities worried had gotten a bit backed up. You probably don’t want to think too hard about what exactly the issue there is or why hundreds of thousands of toilets whooshing all at the same time will fix it.

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