But the harbour - and the marine businesses in it - is protected by East Head, which is now under serious threat from the very waters it protects the harbour from.

With more than 10,000 registered vessels in the harbour and 28,000 regular users supporting the 14 sailing clubs and 16 boatyards and marinas, the marine industry in the harbour at Chichester directly employs more than 650 people and has an annual turnover in excess of £200m.

A key feature of East Head, known as The Hinge, is being eroded, and was temporarily breached in 2004. If East Head is lost in its entirety, not only would an outstandingly beautiful feature of the South Coast be lost, but the harbour will, in addition, lose the most attractive and safe anchorage in the eastern Solent.

The fabulous landscape, the coastal footpath network and other special qualities resulted in the harbour being designated an Area of Outstanding Natural Beauty in 1964. These attractions combine with its importance for habitats and wildlife to make the harbour a magnet for 1.5m tourists a year generating £15m per annum for the local economy.

Losing East Head will expose the whole of the Chichester Channel, from the harbour entrance to Cobnor, to the open sea, and this stretch of sheltered water, for generations an area of safe sailing, will be lost.

If this happens, the effect on the local economy will be profound in the marine industry and supporting businesses, such as shops, pubs and chandleries. The loss of a nationally important recreation centre will impact adversely on the boatyards and marinas, sailing clubs and 13 historical harbour-side villages - the heritage of the harbour will, in short, be lost.

There is historical evidence, supported by research, to show that if a breach forms through the dunes at East Head, a tidal channel is likely to form through the breach and that the breach will not "self-heal".

The same evidence and research shows that when this happens the tidal dynamics in the Chichester Channel will be altered and sedimentation will take place in the main navigable fairways. Although it has not been researched to the same degree, the effect of losing East Head altogether or widening the harbour entrance may be the same.

Only deep channel The Chichester Channel is the only deep water navigable channel, with at least 2.5m below chart datum, connecting the west side of the harbour (Hayling Island, Emsworth and Langstone) to the East side (Dell Quay, Birdham, Itchenor, Bosham, Thorney Island, West Wittering).

It is also the only channel that gives access to the open sea for six villages and sailing centres on the east side of the harbour. Vessels with a draft of in excess of 2m are commonplace in the harbour and the Harbour Conservancy has for 30 years always tried to lay its deep water aids to navigation in 2.5m of water below chart datum.

The deep water navigable part of the Chichester Channel is at its shallowest, with only 1.9m of water below chart datum, at its junction with the Emsworth Channel; the very place that sedimentation took place and the inner bar formed when East Head breached in 1963.

This junction is a crossroads for vessels transiting east-west in the harbour and for vessels entering and leaving the harbour from its eastern part.

On busy days it's a vessel choke point and its proximity to Hayling Island Sailing Club, the club with the largest dinghy fleet in the harbour, adds to the congestion.

The impact of sedimentation and an inner bar forming in this part of the harbour will bite progressively as the bar gets higher and the water shallower. Ultimately, the effects will be disastrous for mariners, the local community and businesses.

The harbour will become less safe with the hazards of grounding and collision increasing and the associated risks to life and limb increasing for all the 10,000 vessels, 28% of all recreational craft in The Solent, and 28,000 people using the harbour regularly.

The harbour will very quickly lose its attraction and eventually become untenable as a base for its 5,000 cruising vessels. Visiting vessels will not come to the harbour.

The large fleets of historical day racing keelboats will be unable to race in the harbour and will move elsewhere.

The dinghy fleets will become increasingly restricted in their use of the harbour and will move elsewhere.

Two harbours It will create two harbours bringing with it administrative, safety and policing difficulties.

One of the drivers for the creation of the Chichester Harbour Conservancy, uniting two harbours into one, was to overcome these very difficulties.

Speaking to Boating Business earlier this year, John Davis, manager and harbour master at Chichester said that, currently, marinas and marine businesses in the area are made aware of the situation via Harbour News, via regular meetings with the marinas, and the Harbour Conservancy's website at conservancy. co. uk with its regular reports and updates on the situation.

"They are supportive of what the Harbour Conservancy is doing but, to date, have not been invited to make a financial contribution to the work conducted, " he explained.

Asked about what further research/study work addressing the problem at East Head, he explained that, over the years, there have been a number of studies and that, in his view, there is probably not much more to be gained from further modelling and hypothesising.

"One of the problems is that it is difficult to get a consensus from the consultants on the interpretation of the work that has been conducted, " said Davis. "We are now waiting for the outcome of the review of the Coastal Defence Strategy for the Pagham to East Head sector of coastline before we can take any further action, but have funders in place to pay for further recycling of material at East Head in both the short and long term - if this measure is enabled by the Coastal Defence Strategy group."

Chichester District Council (CDC) spokesperson David Lowsley confirmed that it is still awaiting completion of Coastal Defense Strategy, which is nearing consultation phase.

"Any further studies or schemes are dependent on DEFRA funding, which is unlikely for the next two years at least, " he told BB, "so funding will need to be sourced elsewhere. Work will need to be commissioned and carried out by all the interested parties.

The solution will, of necessity, be the best compromise between the many competing and at times opposing views.

The site is massively protected by a number of environmental designations which all are legally obliged to heed."

Local interested parties - including the marine industry - will be targeted for their views and comments during the consultation phase, he explained, noting that the CDC's assessment of the impact of the loss of East Head was broadly similar with that of the harbour master.

"The sea has already once broken through The Hinge by over-washing a narrow strip connecting East Head to the shore, " he explained. "If this is allowed to continue a new tidal channel may form, exposing to wave action areas that are currently sheltered and damage to fragile footpaths and wildlife habitats may ensue."

Mobilisation of material The current understanding is that a tidal breach would result in the mobilisation of a great deal more material and as a result, sedimentation patterns in the harbour may change, reducing the navigability in large parts of the harbour, he added.

"East Head could disappear altogether and the exposure of the Snowhill Creek flood defences to increased wave action could result in their failure, and consequent flooding of West Wittering village centre."

When The Hinge was breached, around £15,000 was found to provide 13,000 cubic metres of sand and shingle that were recycled from the northern tip of East Head back to where it originally came from in The Hinge, in order to seal the eroded gap in the dunes to a depth of some two metres, but funding for a long term solution for East Head is unlikely to come from central government sources (such as DEFRA) however, Davis believes, and any scheme must be coherent with the Coastal Defence Strategy for the area.

Because of the environmental designations that apply to the whole of Chichester Harbour, it's most unlikely that extensive hard engineering (such as rocks, groynes, or gabions) would be used to protect East Head and solutions such as these would be unlikely to be permitted by central government and will, therefore, be ruled out as an option in the Coastal Defence Strategy.

Sand dunes and shingle banks in a maritime environment are ephemeral features and without hard engineering they will change in size, shape and orientation and may be lost entirely. It follows that change at East Head is inevitable and if the feature looks like being lost, other means of maintaining its value need to be found. This could it is understood, take the form of beach management of the adjacent coastline, in order to improve sediment flow into The Hinge, and longer term recycling of material may provide a way of maintaining the feature for, perhaps, a generation.

Against this background, the Harbour Conservancy has sought to inform the Coastal Defence Strategy and has submitted its "position statement" and "required outcome" to the Strategy Steering Group.

The Conservancy says it will "seek to maintain and protect" the special qualities of East Head as a significant dunes feature, prevent the adverse impacts that its loss will have on the wider harbour and work to ensure that the evolution of East Head should not prejudice navigation by causing sedimentation in the main navigable channels, or result in the loss of the sheltered anchorage and shelter provided to small vessels in the Chichester Channel.

In seeking a sustainable and economically viable solution for the long term maintenance of East Head, the Conservancy says it accepts that the feature may change in size, shape and orientation; that some "managed realignment" may be appropriate. It also agrees that hard engineering should be kept to the minimum necessary to achieve the desired outcome.

Recycling necessary Recycling of material may be necessary if there is insufficient sediment in the system because of sea defences elsewhere, and the life of the scheme may be less than 25 years and may not stand a 1:100 year event.

"Whatever scheme is adopted, there will be a need to review, from time to time, any strategy adopted, " noted the Conservancy, "and we await the publication of the Consultation Document for the Coastal Defence Strategy, which is due out shortly."

"There is estimated to be little risk to life from the changes at East Head, " Lowsley explained, noting that protection of East Head may therefore be a lower priority for funding than other coastal areas.

"Any future works may, therefore, have to be funded by the public with contributions from other agencies, " he said.

Among the bodies with powers to influence the solution are English Nature, the Environment Agency, the National Trust (the landowner) and Chichester District Council, which must take account of sustainability and environmental issues as well as local economic and wider amenity interests.

"The challenge is to come up with a solution that preserves the value offered by East Head to the community, in particular that it meets the requirements of public access, flood defence, harbour navigation, nature conservation, viability and cost effectiveness, such that it attracts private and other funding, " he concluded.