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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It will be dry with variable cloud, although fog patches could be possible later.
Perhaps a few bright spells, but generally rather cloudy with some showery rain possible at times, especially in the afternoon.
It will cloud over tonight, with the risk of rain on Sunday.