That was followed by a collapse of a roof panel at the stadium on May 27 after rainwater collected on the roof.

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That made it easier to purify the rainwater that in Singapore is fastidiously collected wherever it can be in streets and ponds, even on tall buildings and bridges before being taken by drains to reservoirs, and thence to treatment plants where it is cleaned to drinking-water standards.

ECONOMIST: Every drop counts | The

Meanwhile, rainwater would trickle down the curved exterior of the four-level home where it would be collected, then purified, for drinking water.

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