Guanabara bay will host both rowing and sailing when the Olympics arrive in Rio in 2016. But the bay is contaminated by sewage. Brazil's olympic yachtswomen hopefuls Isabel Swann and Martine Grael say at times the water is more like spinach soup.

They are concerned that if the bay is not cleaned up the pollution will be an embarassment during the games. Rajan Datar joined them sailing.

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