Fareham based Boskalis Westminster Ltd has started work on the £31million contract awarded in June by the Defence Infrastructure Organisation (DIO) to prepare Portsmouth harbour for the arrival of new carriers next year.

The carriers will be significantly larger than any ships that currently use Portsmouth Harbour so Boskalis Westminster Ltd will dredge the approach channel, inner harbour area and berth pocket, making them deep and wide enough for the new ships.

While the dredging vessel is not due to start its activity until next month, a crane barge, known as Strekker, has already begun removing debris from the dredge site which could cause an obstruction.

In total around 3 million cubic metres of clay, sand and gravel will be removed from the harbour.

The dredge will meet stringent environmental requirements set out in the marine licence and take into account the local marine and coastal environment, without impacting on the existing operations at HMNB Portsmouth.

Captain Iain Greenlees, Head of Infrastructure at the naval base, said the start of the preparatory dredging works marked another important milestone in delivering a naval base ready to support the new aircraft carriers.