The 500 pound World War Two device was picked up during dredging work.
Dorset No Longer In Drought
Parts of England - including Dorset - are no longer in drought following the wettest April on record and continuing rain this month.
The Environment Agency says drought status has been lifted for 19 counties in the South West, the Midlands and Yorkshire.
It says water companies in those areas are unlikely to impose hosepipe bans on customers.
But parts of East Anglia and the South East remain in drought with hosepipe bans in place.
In a statement on the Environment Agency's website, it says:
"South West England, the Midlands and parts of Yorkshire are no longer in drought due to the recent rainfall.
"It is unlikely that water companies will now impose hosepipe bans in these areas over the summer.
Parts of East Anglia and South East England remain in drought, with water company there still keeping restrictions in place on public water use."
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
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