Palm island

Beside the seaside

To mark the end of this year's European holiday season, E&T takes a plunge into the past and present of beach and coastal engineering.

Most people today would see beaches as places of relaxation and entertainment, but in the past they were important for the sustenance of human life.

It is said that evolution was hastened when the predecessors of the human race enlarged their brains by consuming shellfish collected from rock pools on the seashore. And even though the majority of fish we consume now come from factory ships trawling the oceans or from large-scale farming, some fishing is still done from small boats, drawn up on the beaches at the end of the day.

From the late 18th century, towns in Europe expanded round beaches that had become popular places from which to indulge in sea bathing for health.

On the vast flat beaches of northern France, land yachting, an activity started by Louis Bleriot in the 1900s, became popular. Others became a stage on which to test car engineering to it limits: in the 1920s there was a hectic rivalry between Henry Seagrave, JG Parry-Thomas and Malcolm Campbell for the world land speed record.

In 1926, on Pendine Sands in North Wales, Parry-Thomas pushed Henry Seagrave's record up from 152 to 169mph and the following day achieved 171mph. Malcolm Campbell, again on Pendine Sands, achieved 174mph early the following year. This was the last record to be set in Europe, since Parry-Thomas was killed in a further attempt in March, 1927. 

Later that month, Daytona Beach in Florida became the location where Henry Seagrave finally reached 200mph.

Co-working with nature

The roar of car engines is the last thing holidaymakers want as they roast themselves on regimented sunbeds in resorts all over the world, rousing themselves only for a languid dip in the sea. They probably don't spare a thought for what they are lying on - one of the best defences against flooding and coastal erosion.

As Bert Groothuizen, manager of marketing and communications at Van Oord, says: "Beaches, including the dunes, serve as a primary defence of the coast, in fact the most important defence line against attacks by the sea."

Van Oord is one of the largest global players in the field of marine engineering and dredging, reclamation and the construction of artificial islands, involved for decades in the renourishment of beaches.

Most beaches are, of course, engineered by nature; the result of changing sea levels and the erosion and transport of the resulting material along the coast by the process known as longshore drift.

Before human intervention they were constantly changing, disappearing in some places and building up in others.

As settled communities were established along the coast, the constant and sometimes sudden changes brought on by the sea became unacceptable and attempts were made to stabilise the coast with the construction of sea walls built first of earth and later of concrete or stone. But these and the construction of breakwaters cause problems.

Groothuizen says: "If you build infrastructure out into the sea you will definitely effect the natural transport mechanisms causing the accretion of material on one side of the breakwater and erosion of the coast line on the other side. This is one of the main reasons for beach replenishment or renourishment."

While this renourisment is primarily for reasons of coastal defence - in the Netherlands especially - in other countries where the climate is hotter, like Spain and Italy, and where a large part of their GDP comes from tourism and the loss of a beach can well mean the destruction of the local economy, it is pretty much a matter of survival.

Groothuizen says: "You compensate for the losses after a storm or prolonged bad weather by replacing the sand in an artificial way instead of leaving nature to do the repair work, which will of course eventually happen. We speed up the repair work".

Another firm involved in beach renourishment is Westminster Dredging, which is celebrating its 75th anniversary this year. Part of the Boskalis Group, one of the largest dredging companies in the world, it has completed several projects in England, moving one million cubic meters of sand to replenish the beaches at Bournemouth and two million cubic metres to the Lincolnshire coastline.

Matt Hosey, coastal development manager for Westminster Dredging, also emphasises the recreational aspects. "These schemes are funded under the Coast Protection Act 1949.

"However, the beaches also provide a terrific amenity that may have provided significant intangible benefits when compiling the cost benefit analysis, particularly for beaches such as Bournemouth where tourism plays a significant role in the town's economy."

Soft engineering

While in Europe the work mainly involves maintaining long-established beaches, in some Gulf States beaches are now being created to build up tourism.

"Sheik Mohammed made a master plan for Dubai in the late 1990s in which he concluded that the only thing he would have when the gas or oil had run out was sand, sea and Sun and that the only way to develop a sustainable economy from this was by tourism," says Groothuizen.

"But he realised that 60km of coastline was not enough to accommodate the 15 million tourists he aimed for.

"The most important part of his plan was to increase the amount of beach. With the first palm island, Jumeirah, which Van Oord built, we doubled the total length of beaches in Dubai."

Van Oord has been involved in the construction of The World and two of the three artificial Palm islands in Dubai, including Palm Deira, the largest land reclamation project in history involving the movement of nearly 1.1 billion cubic metres of sand and 150 million tonnes of rock.

The completion of the three palm islands and The World Archipelago will, by 2013, have increased the coastline to 226km, including 121km of beach front.

Great care is taken with choice of sites for extraction of material for beach re-nourishment and of the effects of work on the environment.

Hosey emphasises that work is planned around environmental windows to avoid the seasons for nesting birds and seal pupping.

He says: "Shingle beaches in the UK are often host to rare plant species. We aim to identify these with our clients and fence off these areas during construction."

He adds: "Where possible, Westminster Dredging aims to improve the environment through the re-use of maintenance/capital dredgings in the construction of a new habitat.

"In 2006, we re-used 700,000 cubic metres of silts from deepening works in Harwich to create a 110 hectare wetland in Wallasea."

Groothuizen agrees: "Instead of just counterbalancing the negative effects, we try to design right from the start with the aim of having a positive effect on the environment."

However, the long-term environmental effects of so much coastal engineering are not yet known.

"Van Oord," Groothuizen continues "is one of the companies that has taken the initiative to set up an institute in the Netherlands, together with other parties including universities and environmental organisations, to study the possibilities of designing marine infrastructure with the aim of enhancing the environment."

The Institute, called 'Ecoshape, Building with Nature', has selected projects in the Netherlands, Singapore and Australia to be studied to discover the final effects.

It is certain that with the inevitable rise in sea levels in the next decades, coastal engineering will become increasingly important.

While communities that have developed in areas below sea level, like the Netherlands and Romney Marsh, southern UK, will continue to be protected by primary lines of sea defence, the sea and rivers will be allowed to return to other low-lying areas with a policy of managed retreat or realignment, thus taking the pressure of other parts of the coast. This soft engineering, or 'Building with Nature', which includes the maintenance and creation of beaches of sand or shingle, could be seen as a return to the engineering by nature that created the world's coastlines in the first place.

Recent articles

Info Message

Our sites use cookies to support some functionality, and to collect anonymous user data.

Learn more about IET cookies and how to control them

Close