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.
More top news
A drug and alcohol abuse charity has warned a new law making psycho-active substances illegal won't necessarily solve the problem.
This weekend's show is the first to take place there since new rules came into force after the Shoreham aircrash.
The family of two little girls who were left paralysed following a crash say they will never forgive the driver who caused the collision.