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BOB HIRSHON (host):
Natural water scrubbers. I’m Bob Hirshon and this is Science Update.
Whenever it rains, torrents of oily, polluted water pour into storm drains and out into rivers. In a new study, researchers showed how rain gardens, which are small patches of earth planted with hardy shrubs, could help. They’re located so that they intercept runoff before it reaches storm drains, and the team found they removed up to 99% of common pollutants.
In related research, scientists measured pollution levels of an urban river as it entered a band of forest, and again as it passed out the other side . They found that when streams flow through even a single mile of undeveloped, undisturbed forest, pollution levels drop dramatically.
Both methods could stop pollution before it reaches major rivers, bays and estuaries.
I’m Bob Hirshon, for AAAS, the science society.