2012 Lives: Green algae covers the River Lea around the Olympic site
Green Algae could cover the waterways that surround the Olympic site in 2012.
The duck weed thrives in hot sunny conditions and grows at a rapid rate on the River Lea every July.
Chair of the Ramblers Greater London Forum, Len Banister, says: "It's not good for rivers to be covered to this extent."
"It stops sunlight getting down to lower depths, this reduces food levels and oxygen levels."
Len thinks the waterways surrounding the Olympic site in Stratford could look the same way during the Games.
"Given that this is July and since I've known the River Lea navigation, every June there is this problem with algae, and given that the Olympics are going to be held in July there's a real problem making sure that this is cleared away.
"They're going to need quite a few craft cruising up and down the river to keep this under control, I think."
Len is one of BBC London's contributors to the "2012 Lives" project, who will tell their own stories concerning the 2012 Games coming to East London.
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