According to BBC and other news sources, the city council of Bulawayo, Zimbabwe's second largest city with a population of 1 million, are asking all the residents to simultaneously flush their toilets in order to clean out the pipes.
Zimbabwe has been suffering a severe drought. Residents in the town of Bulawayo have only 72 hours of water a week. Two of the city's five supply dams have dried up, and the situation is unlikely to get much better until a proposed pipeline is built--a project not slated to be completed until 2014.
The prolonged drought has led to sewage building up within the system while residents wait up to three days sometimes to flush. Pipes have already reported to have burst from the dryness and weight of the waste. This flush will help clear all the waste from the system.
Residents are not entirely pleased. "Our leaders are a joke," says one resident. "What they should be doing is finding money from donors to buy new sewer pipes."
If there is an engineer who can explain how this would work to me, I would appreciate it.