The 500 pound World War Two device was picked up during dredging work.
South Coast Caught Up In Storm Angus
The South Coast's braced for more heavy downpours - and gusts of up to 50 miles an hour - as Storm Angus continues.
The Met Office has wind and rain warnings in place across Hampshire, Dorset and the Isle of Wight - until midnight.
The website says:
"On Monday a further broad area of heavy, persistent rain will extend northwards across southwest England and Wales. The heaviest rain is expected to reach southwest England in the early hours of Monday and to reach north Wales by around the middle of the day. Although the more persistent rain should clear from southwest England into the afternoon, heavy and possibly thundery showers are likely to follow.
"Strong northeasterly winds will also develop for a time giving gusts of 40-50 mph.
"Please be aware of the possibility of localised flooding and disruption to transport.
"Some 20-30 mm of rain may fall in a 3-6 hour period in places, with as much as 40-60 mm possible locally through the whole of Monday. The greatest risk of disruption due to flooding is expected to be across parts of southwest England, Devon in particular, where the ground has been left very wet from Saturday night's rain. A separate Amber warning will cover this aspect."
The Environment Agency's warning people in places like Swanage, Corfe Castle, Weymouth and by Hampshire's River Blackwater.
There were temporary road-gate closures in place along Clarence Esplanade. These were due to be re-opened today.
Fire fighters in Dorset say they had lots of calls most about flooding around Poole and Bournemouth at the weekend, and Swanage High Street was closed due to flooding.
Fire crews in Christchurch got called to a house after a tree fell and knocked a chimney over near Hillside Drive in Westbourne.
640 men were killed when the South African troop carrier was hit by a cargo ship in 1917.
The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
Two Girls Indecently Assaulted Last Sunday
Recently Played Tracks
On Radio: Rich and Zoe
6am - 10am
Text 'SOUTH' to 82122
Now playing: Non-stop hit music
Deposit £10 to get a £40 Welcome Bonus - That's £50 to play bingo, slots and more!*
Over 50 tracks to make you feel-good. New album out now...
Find your local four day weather report here.
What's happening on the roads where you are?
Make Heart the soundtrack to your day and you could be a winner with great prizes up for grabs throughout the day.
Find out more about some of the companies advertising on Heart.
Get some great ideas on how to advertise your business on radio, online and on mobile.