The waters around Cornwall are famously clear, but occasionally a storm turns them murky – and, depending on your viewpoint, that is the situation which is creating the waves around Falmouth.
For many, the old port's proposed harbour development plan is clear-cut – there is no storm, just a very obvious economic need. For others, there's a maelstrom in the making and the first victim in the firing line is our precious environment.
Let's begin by attempting to put the whole debacle into a concise nutshell, or cockle-shell would perhaps be more apt, given the habitat concerned.
In the world of shipping, size matters. Big is beautiful. Today's vessels are bigger than ever before, which means they have deeper draughts – which in turn means there's a need for deeper harbours.
Falmouth Harbour Commissioners say a crucial area in the approaches to their haven will not be deep enough for the ships of the future – indeed, they claim the five-metre minimum depth is not enough for many of the passing cruise ships today, which would otherwise call in, helping to revitalise Cornwall's economy.
But – and here is the big but – conservationists point to a rare form of sea-bed that exists in the area which would have to be deepened, saying that some of it would be destroyed if dredging goes ahead.
It's called maerl – a coral-like seaweed made of a hard shell-like substance – and, like coral, it is fragile and slow growing.
For years now in this country a basic equation has existed when people have added the word "rare" to the word "habitat" – you could write it down as "r+h = 0". In other words, rare habitats mean zero development.
However, it's well known that the present government is keen to make changes to this equation – Chancellor George Osborne has uttered many a comment about not allowing over-fastidious environmental demands to stand in the way of economic development. Indeed, the government has demanded an official review of the UK Habitat's Directive – the results of which should be known in March or April.
So conservationists like Cornwall Wildlife Trust's marine conservation officer Tom Hardy now believe the arguments being fought at Falmouth Harbour will become nothing more, or less, than a national test case in the battleground of economic need versus environmental sustainability.
Mr Hardy further muddies the waters lapping around the Fal estuary by saying that the harbour commissioners have alternative options which they can pursue to keep the port economically viable.
For their part the commissioners claim their "Port of Falmouth Master Plan", as it's grandly known, bends over backwards to take everyone's views into account – they have even proposed a small experimental dredge in which a team from Plymouth University will see if it's possible to cut a trench and re-lay the maerl so that it can live happily ever after, albeit a few metres deeper than it does now.
The Western Morning News was also told in no uncertain terms by Falmouth's harbour master, Mark Samson, that the port will fall into decline if the deeper approach fails to get the go-ahead.
Capt Samson took us out to sea on a fact-finding mission so that we could see for ourselves exactly what he and his commissioners have in mind, and why.
This was worthwhile because when I refer to the master plan being "grand" it is worth knowing that the harbour, with all its many marine-related businesses, presently provides around 1,000 full-time jobs and has, it almost goes without saying, a massive impact on the local economy. Indeed, Capt Samson says it is now the biggest single industrial site in the county of Cornwall.
He adds that its economic status will not only be reaffirmed by the dredging, but it will grow thanks to various new opportunities that include a potential threefold increase in cruise-liner traffic.
I was given a cruise-liner captain's perspective so that I could understand why the commissioners are so keen on a deeper approach to their quays. For readers who don't know Falmouth Harbour, it is tucked behind a thin high peninsula upon which stands Pendennis Castle. Between this and St Anthony Head to the east lies the mouth of the estuary, or "drowned river valley" to be more accurate in geographic terms.
A deep channel runs north between the two headlands and enters a huge body of water known as the Carrick Roads – but if you want to reach Falmouth Harbour, tucked behind its protective ridge of land, you must turn left once you pass an inconvenient blip in the waterway called Black Rock. Instantly, you're out of the deep water channel, some 60 metres deep, and passing over a sea-bed which is less than 10 metres under the waves.
As the pilot steering the harbour master's launch showed me on a screen – the banks of the deep water channel are like underwater cliffs, within just a couple of metres you're over a shelf – and this continues all the way up to the wharves of the harbour. At its minimum point, the sea-bottom is just 5.1 metres under median sea levels.
That's not enough for the big liners, whose captains have the choice of either "parking" out in the narrow deepwater channel and using tenders to take passengers to shore, or simply sailing on by – which is what they'd do in anything but fine weather.
As a land-lubberly layman, I could see the logic in the harbour commission's proposal. Their argument is black and white – there doesn't seem much room for ambiguity.
But conservationists like Mr Hardy say the commissioners themselves have put forward other options which would see the port thrive without cutting into the maerl.
Capt Samson attempted to throw some light on why he believes the need to create a deeper channel is so straightforward…
"We have a minimum draught of just over five metres which is pretty shallow if you look at modern ports like Rotterdam – they are looking at 17 to 18 metres in terms of their next dredging schemes," said Capt Samson as we looked at charts in his office.
"Larger cruise liners are between eight, maybe nine, metres draught – we want to dredge to 8.2 metres in our main channel because we calculate that will give us the opportunity to attract 75 per cent of the cruise liner market.
"A lot of the region's harbours have turned into museum pieces in the sense they've stopped keeping up with the shipping requirements of the day – Falmouth has been a commercial port for all types of vessel for a very long time and we are going to need to do something about our depth if we want to go forward.
"It's not been an easy process," Capt Samson says. "Ten years ago it became apparent we needed to do something about it – but we always knew it wouldn't be easy because of the environmental sensitivities and concerns. So there was a staged process, refining the plans and then putting the application in.
"Our plans are well supported locally and across the county, but the maerl has become a very particular issue in the economy-versus-environment argument. People who see Falmouth as a working port want it to continue – there is general agreement that it is the strategic port for Cornwall and vital for the future – so it then comes down to how you get the consent in order to carry out the dredging operation.
"It's by far the biggest hurdle. There are works ashore that will improve the performance of the port to some extent – but to unlock the port's potential you do need the deep water. The Port Master Plan is complex – it deals with the shipyard and tenants and their plans – some aren't reliant on deep water and they will go ahead. But in terms of jobs being created it's about bringing in the bigger vessels."
At this point I put it to Capt Samson that his critics believed the commissioners themselves have outlined other options which talk about the profitability of the port continuing without the deepwater channel being dredged.
"There are a number of options – we do look at options that don't include dredging," shrugged the harbour master. "But, I repeat, economic gain can only be achieved by having dredging as part of the master plan. And we've estimated it's less than two per cent of the entire maerl in area of conservation area that will be affected.
"If we can't dredge we will see the commercial port go into a decline and ultimately the land would be used for other purposes.
"Quite often people say it would be an ideal site for a marina: 'What do you need all these nasty ships for?' they ask. But if you look at the employment in a marina compared to what we have here – there's no comparison at all – it's a quantum order smaller.
"There is no other option. If we don't dredge the channel we are going to see a gradual decline – and that's significant, not just for Falmouth, but for Cornwall and even the capability of UK plc. We do need ports of varying capability. We are a very great strategic asset for the UK.
"It would be a lost opportunity," Capt Samson insisted. "There are markets we could really develop (if the dredge goes ahead) by meeting the needs of modern shipping. And that means jobs in the local economy going forward.
"It's a general package. If we have deeper water it will help the cruise business – but that is just one area where it is easy to measure direct economic effects because we know how many passengers they carry and the prognosis is very good.
"The passengers love the county and we get good feedback – but the larger vessels won't come now unless they can pull up alongside. We've had cruise-line operators say to us they'd come here – so we are confident that we will see a threefold increase in our current activity (of around 35 cruise liners per year). And that's already beginning to fall because they are already building larger ships."
These are all strong arguments and might well overshadow a type of rare seabed that no one but divers will ever see – a seabed, by the way, which was until recently mined for commercial purposes. Fal maerl was dredged and landed at Truro quay from where it would be transported as an agricultural fertiliser.
But, partly because of its rarity, it was protected by the UK Habitats Directive – which is why Tom Hardy says that destroying an area of it will require legislation to change at a national level.
"This isn't simply dredge or no-dredge – every SSSI and every other protected area in the country could be threatened by what goes on here," Mr Hardy told me, while continuing to emphasise that Cornwall Wildlife Trust is fully behind backing the economic viability and future of Falmouth Harbour.
I asked him how he could take what seemed such a double-sided stance when the reasons behind creating a deepwater channel seemed so clear cut.
"If you go through the harbour commission's own documents in detail you will see there are other options," he replied.
Option B in the listing talks of: "Maximising port uses without dredging. Investigating the possibility of a limited amount of port land being redeveloped for alternative uses."
"We want to see a real valuation between all the options mentioned," said Mr Hardy.
"People need to know all the options," he said. "I don't think Falmouth will die (if the dredging doesn't go ahead). Making a decision at this time is tricky: what will they say if the economic benefits don't happen – if the super-liners don't arrive?"
It's a good question. Like the one which asks if the maerl will survive if it is carefully scooped up and re-laid (Mr Hardy thinks not) – and like another question which asks where all the development funds will come from if every item in the harbour master plan is given the go ahead…
Of course, various people have answers to all these questions and to the many more which could be asked outside the overview given here.
However I will underline a belief I came away from Falmouth with – in an unscientific survey carried out in a couple of hours this week I couldn't find a single person in town who was worrying about the maerl beds. Some of the people I talked to hadn't even heard of maerl, others weren't bothered if two per cent of it were to make way for economic opportunity.
Maerl is out of sight and out of mind for most people – and if the Falmouth dock debate really does become a national test case it could be one of the easiest environment battles that development-minded politicians have ever fought.
Let's leave the last word to the Chancellor himself – in his autumn speech, Mr Osborne said: "The Marine Management Organisation and the Port of Falmouth have agreed a way forward on a scientific trial to resolve environmental issues around development of the harbour. A decision on the developer's marine licence application will follow if the trial succeeds. If this application is then successful, it is anticipated that development could proceed in early 2013."
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