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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Cloudy for most through Saturday with early intermittent rain becoming heavier and more widespread later. Drier and brighter on Sunday.
Start your weekend with a smile by reading the latest in ITV News Anglia's Christmas Shout Out series.
The Norwich South MP Clive Lewis has been made joint favourite with the bookies to be the next leader of the Labour Party.