The tidal barrier which will protect thousands of homes and businesses from the risk of flooding.
Work on the 38 million pound project in Ipswich started today and it is due to open in 2016.
The council says it will secure the future of the town, and encourage economic growth.
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The Broads Authority wants to rebrand the area as a National Park
Saturday will be largely cloudy with a continued risk of heavy showers or thunderstorms. Sunday will be dry with sunny spells.
There continues to be a risk of thunder tonight and tomorrow but the weather will become drier and clearer by sunday.