Photo: Invincible class aircraft carriers in the historic dockyard as seen from Explosion! The Museum of Naval Firepower. © 24 Hour Museum.
A massive development scheme at Portsmouth Naval Base, involving dredging and the possible creation of a new deep water channel could impinge upon the historic harbour's accumulated layers of maritime history.
Portsmouth has long been one of the UK's most important harbour sites with a recorded history going back to the Romans and taking in the likes of the Mary Rose. With such a wealth of history in the area, local archaeology groups and experts may well be concerned about the impact of the scheme on the historic environment.
The £150-200 million plan will make the Portsmouth Naval Base capable of accommodating what will be the Royal Navy's largest ever vessels, two new aircraft carriers weighing between 60 and 70,000 tonnes each.
As well as refurbishing the base's jetties, the plan would involve the dredging of the main channel inside the harbour by another two metres. There are also plans to create a new approach channel 200 metres wide, which could be dredged as deep as 14.5 metres.
Photo: the Mary Rose sank in the Solent in 1545, was raised in 1982 and is now being conserved at the historic site.
But experts insist that with the help of a long consultation period and significant surveying, Portsmouth's historic waters and archaeological environment will be protected.
A statement issued by the Royal Navy today has announced that a lengthy consultation and environmental assessment will be carried out.
“Portsmouth is recognised by the Ministry of Defence as being of environmental importance for many reasons, including nature conservation, fisheries and archaeological sites.”
“Therefore the Warship Support Agency (WSA) has commissioned a firm of specialist consultants to undertake an environmental study in preparation for a more detailed environmental impact assessment later this year.”
It is, however, the new approach channel, with its proposed route through the Mary Rose historic wreck site, that would have the greatest impact upon archaeological material.
As reported by the 24 Hour Museum yesterday, the Mary Rose Trust, in part prompted by the project, is planning a series of dives to clear the site of debris and salvage any historic material that might still be there.
Photo: an aerial view of the vast Naval base at Portsmouth harbour.
Mike Power, Project Leader at the Warship Support Agency told the 24 Hour Museum how a geophysical survey will be undertaken later this year, while Wessex Archaeology has been commissioned to carry out a study of the area.
“We need to protect the resource,” said Mike, “and we are bound by English Heritage to protect that resource, but exactly how to do that is somewhere down stream. The whole idea is that we know what's in the way so that we can deal with it in a grown up way, rather than just start digging.”
Adding that while any site of a new approach channel would need the most archaeological attention, Mike explained that in the harbour itself there could be ancient and even palaeolithic material.
“Any digging work is a long way down the line, but there will be plenty of time to sort out these issues, but the sooner we do the better so that we know what the constraints are.”
Photo: yet another artefact recovered from a wreck in the Solent, in this case from Invincible which sank in 1758.
Of the Mary Rose wreck site Mike added, “one of the proposed routes clips the site and clearly if we were to use that site we will have to take some mitigation into account.”
Chief Executive of the Mary Rose Trust, John Lippiett acted swiftly to put forward his organisation's position on the plan.
“We acknowledge that the Mary Rose historic wreck site could be compromised by one of the proposed routes. We also publicly recognise that the project team is acting responsibly by consulting with all key stakeholders, including ourselves and English Heritage. Since the project is at a consultative stage, it would be premature to speculate further.”
“However,” he added, “the public and the archaeological community should be reassured that detailed and consultative discussions are taking place.”