Langstone Rock is a red rock of Permian sedimentary breccia with some sandy horizons at the top. The breccia is known as the Langstone Breccia and it is late Permian. The rock was once firmly attached to the adjacent cliffs of Dawlish Bay and has been separated by the contruction of a cutting of Brunel's railway line in 1846.

Originally this was Langstone Point, a promontory, not Langstone Rock. It is not composed of very resistant material and has a warning notice about falling debris. The proprietor of the cafe told me that some material falls almost every day from the rock, but there is not much obvious evidence of major cliff falls seen when visited on student field trips almost every year. The groyne has not become much separated, as yet from the rock so erosion cannot be very fast (although there has been repair work to the landward end of this groyne). East of Red Rock Cafe brickwork has been used to try to reduce erosion. A columnar structure in the sea near the cafe is the relic of a different approach to sea defence, but this method has not been continued. The remaining circular base of the structure is referred to informally at the cafe as the "Dinosaur's Nest".

LANGSTONE ROCK continued

Wave-Cut Platform and Breakwater

At the end of Langstone Rock is a large, granite breakwater or groyne, shown in photographs above (in April 2010 the groyne was showing some major cracking on both sides at the landward end and some failure at the seaward end). This holds back some sand and shingle from northeastward longshore drift. It may, thus, seem undesirable from the point of view of Dawlish Warren. However, it gives some limited protection to the railway and sea wall to the southwest of Langtone rock (i.e. towards Dawlish). That is probably why it has been built. Some sand and shingle could escape northeast through the cave or natural arch at the end of Langstone Rock, shown above. However, a barrier has been built inside this natural arch to retard loss of sand towards Dawlish Warren.

It is obvious that Dawlish Warren, once just an almost uninhabited sand spit has not been a priority in the past. Protection of the railway seems to have been the main concern.

It is interesting to see a fairly extensive wave-cut platform to the east and northeast of the breakwater. This has probably been cut by wave action using sand and shingle for abrasion. There is not much evidence of biological erosion at the foot of the cliff of Langstone Rock on the beach side (southwest). This is because the supply of beach sand and shingle here can, during strong wave action, abrade the Langstone Breccia. On the northeast side the processes may be different because, here, the platform is just above the low-tide level and there is much attached seaweed and various marine organisms.

Because sea-level, has been, and still is, progressively rising, a broad rock platform indicates that erosion has been fairly rapid. Langstone rock obviously extended much further seaward since about Roman times. Before that sea-level was significantly lower and, thus, the wave cut platform probably gives some idea of the Roman geography of the area.

LANGSTONE ROCK continued:

Langstone Breccia - Composition

LANGSTONE ROCK continued:

Sand Liquefaction Structures

The breccia beds of the Langstone Breccia, and also within the Dawlish Sands, have some unusual characteristics (best seen at the base of Langstone Rock). The clasts are very angular and show little effect of clast-on-clast abrasion (there is a small amount). The overall size range of the classts is limited but they are not well-sorted. There are no lag deposits of larger clasts at the base of beds. Of particular note is the fact that there are well-developed desiccation cracks on the surface of a breccia bed. Thus it was a partly cohesive sediment, probably containing a significant proportion of clay.

These features show the beds are probably debris flows. This accords with the occurrence of liquefaction structures at the base of breccia beds. This is a common characteristic of debris flows. The underlying sands have been liquefied and mobilised. In some cases they have moved upwards in a diapiric manner, as shown in the images above.

LANGSTONE ROCK continued:
Polygonal Desiccation Cracks in Breccia

Introduction

Above is the main car park on the landward end of Dawlish Warren and near the railway. This is a large car park which overlies a substantial part of the old Greenland Lake, present before later development and coastal erosion. It is usually easy to park here (there is a car parking charge). Toilets and some small shops and a pub are nearby, and so too are various amusements for children. The buildings are protected from sea erosion by high banks of rock armour and a hard artificial promenade. To see a more natural part of Dawlish Warren leave this area and walk northeastward up the spit. A small nature reserve building is the last and unobtrusive construction which has been built further down the spit. The last part is almost natural (although there is golf course on the spit to the northwest).

As an alternative to walking down the spit, there is quite an interesting path in the opposite direction towards Dawlish town and sea front. This passes the conspicuously red Langstone Rock, which is of geological interest. If you take this route you will be alongside the railway line.

Dawlish Warren is a sandspit with an interesting history of development and of erosion, particularly the latter. Maps and photographs below will show both the development and the vulnerability of the spit, and, in addition, the various sea defences (from timber groyes to rock armour). The spit is, and long has been, at risk of erosion and possibly of almost complete destruction. Various photographs and maps below show the nature of the problem.

DAWLISH WARREN continued:

Maps

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DAWLISH WARREN continued:

Aerial Photographs

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The modern aerial photograph, shown above, a general view of the spit, is courtesy of, and copyright of - The Channel Coastal Observatory , National Oceanography Centre, Southampton University, Southampton.

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Matching Vertical and Oblique Old Photographs of Dawlish Warren

The two fairly old aerial photographs above, one vertical and one oblique match up in terms of features and the extent of erosion. A distinguishing feature for the date is the presence of many caravans near the landward end of the spit. The pictures are probably from the 1960s or 1970s but have not net been precisely dated. They show that there was originally a much greater development of salt marshes, since then largely replaced by mud flats. This probably part of the usual decline in Spartina salt marshes in recent years. Similar changes are taking place in the Solent estuarine system. See: The Lymington - Keyhaven area of the West Solent, and related Solent webpages.

Study both the above photographs, in relation to each other, to understand the changes that have been taking place at Dawlish Warren, in terms of erosion, loss of salt marshes and development by human activities.

DAWLISH WARREN continued:

Rock Armour

Between the present position of the Dawlish Warren sand spit and Langstone Rock the railway line curves fairly abruptly to run westward along the cliff to Dawlish. There is insufficient natural protection by beach material here and it is mainly a large quantity of rock armour is preventing sea erosion of the railway line. There is a sea wall but it is probably inadequate without the additional use of rock armour. It is probable that the southern boundary of the sand spit was originally positioned further south, and the retreat of this has accentuated the problem. The purchase of thousands of blocks of rock armour must have been expensive. Note, though, that in early 2014, there was major erosion of the sea wall in the bay at Dawlish, and destruction of the railway line at a place where there was no rock armour.

The granite was tipped here for sea defences in about 1920 and onwards. An engineers' railway siding was constructed along what is now the footpath and railways brought the stone to the sea wall. The granite is typical Southwest England granite with large phenocrysts of orthoclase feldspar. When weathered it is slightly reddish (this can even be seen in the aerial photograph).

Particular conspicuous is the coarsely crystalline, bluish grey, igneous rock - Larvikite. The rock was termed larvikite (or laurvigite) by Brogger in 1890 after the town Larvik, not far from Oslo. This is the most important Norwegian quarried stone and there are about 20 quarries in the area. It is at the coast of the Skagerrak and is easily shipped across the North Sea to the UK or elsewhere. See the webpage of Stema Shipping Armourstone, who export larvikite.

Larvikite is very coarsely crystalline, like granite, but bluish-grey and darker than granite. It is quite hard and has no significant porosity. It shows the special feature of a beautiful blue schillerization (sparkling crystals). When polished it is often used for banks, pubs, shopfronts and for kitchen worktops. The main components, the feldspar shows cleavages, or minute fractures in the large crystals. There are also some dark, almost black mineral components.

Larvikite has been used for rock armour at Hurst Spit, Hampshire, Lyme Regis, in Norfolk (Waxham to Happisburg) and elsewhere.

Larvikite is a plutonic igneous rock; it originated as magma which has been intruded at depth during Carboniferous to Permian times (about 300 million years ago and round about the same time as the Dartmoor Granite) into the Oslo Graben. This downfaulted trough is an aulacogen (or failed arm) due to the Permo-Triassic extensional tectonics that preceded the development of the Atlantic Ocean.

Larvikite is a rock of Intermediate composition - that is partway in chemical composition between granite (a light-coloured rock - an acid rock, high in quartz and light-coloured) and gabbro (a basic rock, dark-coloured rock - without quartz but with dark iron and magnesium minerals). The conspicuous blue-grey crystals with the obvious cleavage are of plagioclase feldspar, a aluminium silicate with sodium and/or calcium. These form about 80% of the rock. Rather less obvious are crystals which in the field or the hand-specimen appear grey to almost black. These are of augite, amphibole and other mafic minerals and form about 20 percent of the rock. Unlike granite there is very little if any quartz.

(For more information on larvikite used as rock armour see: the Hurst Spit, Hampshire, webpage.)

DAWLISH WARREN continued:

Tourist Facilities Area

The southwest, landward part of Dawlish Warren sand spit is developed, to some extent, with amusement facilities, a restaurant and pub, car parks, toilets etc. This area is very low in relation to sea-level and at risk of being flooded by the sea during storms. As a result there is a substantial sea wall with rock armour, immediately seaward of these buildings. A major indentation a short distance further to the northeast is protected by a sloping sea wall of concrete slabs. These features can be seen on the aerial photograph above.

DAWLISH WARREN continued:

National Nature Reserve

It may be of interest, particularly to Environmental Science and Geography students that Dawlish Warren is an area with problems of conflicting interest. Back in the past, and long before there was any nature reserve, the railway company built a station and encouraged visitors from nearby Exeter and elsewhere. Chalets, some quite substantial, were built on the far end of the once larger Dawlish Warren spit. They were destroyed by sea erosion and this, perhaps, fortunately saved the spit from eventually becoming a highly-developed urban area like the Sandbanks sand spit at the mouth of Poole Harbour. However, holiday facilites were constucted at the landward end near the railway station. They are on a limited scale and obviously desirable to holiday visitors. It seems strange, though, to see a nature reserve adjacent to them. There is no extensive transition between holiday resort through forest or farm land to nature reserve. The two are almost alongside (there is also a golf course present but that is on the estuarine side of the spit and may not conflict with the nature reserve). Inevitably some problems seem to have arisen. In particular there is some conflict of interest between dog-walkers and bird conservation. Had the area been larger and more space available for dog-walkers (as at Hengistbury Head near Bournemouth) then there might have been less problem.

Matters are further complicated by the fact that the spit is reducing in size by erosion. The holiday facilities have received expensive coastal sea defences (which stop before the nature reserve) and will probably survive longer. However, these defences have spoiled the natural environment, both in terms of nature conservation and aesthetically. Discussion of this land-use problem is not the main objective of this webpage, which is intended to be descriptive with emphasis on geology and coastal processes. Students can find out more from the wardens and from other sources, and consider a fair balance of interests. For comparison consider also Studland, South Haven Peninsula at Poole Harbour, and Calshot Spit at the mouth of Southampton Water. One of the most extremely developed sand spit is the main part of Weymouth, very urban but with a large sandy beach. A small spit, The Point, at Teignmouth has been partly concreted over as a car park, and the same has occurred to small sand spits elsewhere (e.g. Haven Houses spit, opposite Mudeford Spit).

DAWLISH WARREN

Gabions

Protective gabions used on Dawlish Warren each consist of a strong plastic network in the form of a box. These contain limestone fragments. This is a cheap form of sea-defence that is not particularly conspicuous or obtrusive. These gabions were placed on the seaward side towards the central part of the stretch of the sand spit. They were originally purposely concealed beneath sand and vegetation so as to give a natural appearance. However, the external sand has been progressively removed and they were visible in places by 2010. Later, by April 2012 they are well-exposed in places, almost to the top of the bank. Generally, at this date they have not failed, and the internal stones are mostly retained without any substantial loss.

DAWLISH WARREN continued:

Central Part of Beach - Timber Groynes

Long timber groynes extend from the sanddunes to the sea in the central stretch of the sea coast of the spit. Groynes were installed in 1962-3, but I do not know whether the old zig-zag one, shown above, is of this date. It is peculiar that there are no barnacles or limpets (Patella) on the lower part of the groyne. Is this because this lower part was once buried within the beach sand? An alternative explanation might be that the lower part is too strongly abraded by sand and shingle for the attachment of marine fauna. Former burial seems more likely.

DAWLISH WARREN continued:

Sand Dunes

The sandspit of Dawlish Warren on the west side of the Exe Estuary in Devon is important regarding former accretion and present erosion. A marram grass dune ridge is a prominant feature on the seaward side of the sandspit.

This spit has not recently accreted though and this ridge has developed many years ago. Now it is in a serious state of erosion and much of it has already been lost. As noted elsewhere in this webpage, hard sea defences and rock armour are present at the landward end of the spit. However, the more natural and further part with sand dunes has less artificial protection and has been subjected to more erosion. The seaward line of dunes, the marram grass ridge, already has small cliffs. As a form of sea defence gabions have placed under the sand dunes at the front of part of the sand dune ridge. However these are now exposed by sea erosion in several areas on the seaward side of the sand spit.

As noted above, the nature reserve has been narrowing to some extent and is vulnerable and is not protected by hard defences. This notice (in 2007) indicates that Marram Grass has been used to stabilise dunes. This plant is common in Britain and it tends to hold sand in place. Thus it is an aid to preventing coast erosion. However, in the long term it prevents active movement of sand dunes and converts them into a type of hummocky, sandy grassland or into heathland (as at Studland). In Oregon, in contrast, there is an effort to preserve (much larger) coastal sand dunes as active mobile features. Thus Marram Grass, which is invasive and alien there, is undesirable and removed wherever possible. Conservation volunteers help to pull it out so as to maintain the natural mobility and character of sand dunes. Southern England is in general a place where coastal sand dunes occur, but they are mostly vegetated or semi-vegetated; go to Qatar or Saudi Arabia to see active and unvegetated sand dunes.

Comparison

It may be interesting to compare Dawlish Warren to the relatively natural South Haven Peninsula, Studland, Dorset and to the contrasting and heavily built-up sand spit of Sandbanks, Dorset,. There are many other sand spits around Britain that are similar in many respects (see the GCR, or Geological Conservation Review publications in Vol. 28: Sand Spits and Tombolos - GCR Site Reports, on British sand spits of which the account by May (2007) on Dawlish Warren is an example.)

DAWLISH WARREN:

The Narrow Neck and Inner Bay

Shown above, courtesy of the Channel Coastal Observatory, is a reduced aerial photograph of the narrow neck of the Dawlish Warren sand spit in September 2006. There has been great erosion here over the years, and obviously it is this narrow part is at risk of breaking through. There is very little separating the open sea from the Inner Bay (the embayment on the Exe Estuary side, i.e. to the north). Note the subaqueous sand dunes formed by the outflowing tidal current in the tidal delta offshore, of which the most landward part is shown.

DAWLISH WARREN continued:

The End of the Spit and Exmouth Beyond

The end of Dawlish Warren sand spit is a low area of sand without high sand dunes. It is not far from the built up seafront of Exmouth. The end part has changed greatly over the years as shown in maps provided above in this webpage.

The photographs above show the end part of the Dawlish Warren spit. It approaches Exmouth, where there has been major urban development. Cliffs of Permian sandstone here are now vegetated and contain ornamental trees and plants. The foreshore has also been developed to some extent but less large building. Hotels, in particular seem to have been built in the past on the old cliff top.

The Maer is an area of sand accretion in the southeast part of Exmouth. It is alongside the outflow channel of the River Exe. Much of the sand may have been derived from Dawlish Warren and adjacent sandbanks on the other side of the river. The prevailing wind direction is from the southwest and this is likely to transport sand in this direction.

For more on the Exmouth area and eastwards to Budleigh Salterton go to the Budleigh Salterton webpage.

DAWLISH WARREN:

Dawlish Warren - Pole Sand Tidal Delta

The outflowing ebb currents from the Exe Estuary produce an impressive tidal delta off Dawlish Warren and Exmouth. Unlike the muddy estuaries of the Solent there is a relatively large supply of sand here, and thus a large ebb delta of sand has been formed.

According to the SCOPAC report on the area: " At Exmouth, the mean spring range is 3.80m and the mean neap range is 1.48 m. Tidal current velocities are relatively weak along the open coast, but in the constricted entrance to the Exe estuary, and its approach channel, they are up to 3 ms-1 during spring tides and 1 ms-1 during neap cycles. These are high velocities, capable of moving large quantities of sediment, up to medium sized sand."

DAWLISH WARREN

Coastal History - Introduction

Over the last 250 years the spit has reduced from 250m to only 50m wide, according to the official Dawlish Warren Website. The Outer Warren and intertidal sandbars are in a state of 'dynamic equilibrium' whereby material is constantly shifting within the local area of Dawlish Bay. The trend in recent centuries has been towards gradual erosion of the spit, and Warren Point has periodically disappeared or even become a detached island.

In the mid 1940s the central tidal creek of Greenland Lake, which separated the mobile Outer Warren from the stable Inner Warren, was filled in by the Water Board.

A gabion-backbone, which stretches throughout the length of the spit under the dune-ridge, was installed to prevent further sea breaches in the early 1970s, when 17 beach groynes were placed every 100m to impede long-shore drift and retain sediment.

After severe storms, there was the installation in 1992 of new rock-armour which protects the base of the spit and the railway main line ( Dawlish Warren Website). This was presumably the larvikite rock armour which is northeast of the older Dartmoor Granite rock armour. The larvikite was brought in by sea.

The sand spit is not expected to last longer than this century, but the matter is now complicated because of relatively rapid sea-level rise. This will be discussed further later in the present webpage.

DAWLISH-WARREN continued:

Dawlish Warren and Dawlish Bay - Chronology of Coastal Events etc.

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1642-1646
During the English Civil War there was a Royalist fort on the end of the spit ( Barber, 2001).

1715-1805
Anne Lytton (or Litten) used to make her way from Exmouth "to milk the cows grazing" on the Warren, via a series of "stepping stones". Late Victorian experts considered that Bull Hill Bank or the Shilley might been where Anne wandered ( Barber, 2001). Apparently, according to Anne's grandson, Samuel Bricknell, his ancestors vividly recalled that the main channel from the estuary into the sea was beside Langstone Point. As Barber (2001) commented there is an old sea cliff and this can be seen extending from Langstone Rock northward (and it is not greatly degraded). It would not be remarkable if an original sand spit extended southwesterly, like the present Weymouth sand spit, especially if Langstone Rock was much larger (giving protection from southwesterly winds). In any case a series of Quaternary channels run under Dawlish Warren as shown by a Durrance (1980). There is a Recent sand and clay fill of a channel down to -22.9 metres under the car park area of Dawlish Warren. A note of caution, though, is that this undated and might be quite early and it is one of many channels under the spit. Diversion eastward of a former channel is known elsewhere on the south coast and occurred in the Solent during the 1703 hurricane (Defoe, 1705). The outlet of the River Otter at Budleigh Salterton seems to have been diverted eastward by the 1824 hurricane. The River Axe at Axmouth has also been diverted eastward. (For discussion - compare to Teignmouth).

1809 - Warren Island
The old 1 inch Map of 1809 shows Warren Island, later incorporated into the Dawlish Warren Spit.
"[By 1898 - see OS map of this date] The sea ... has enlarged the end of the bank opposite Exmouth by silting up the channel between it and what was once Warren Island, whilst the Pole Sand has been driven further up stream at it landward end. The Warren Island between Exmouth and the outer sandbank was in 1809 an alluvial island, reduced to three small inlets by 1839, which had disappeared long prior to 1872." (Ussher, 1913).

1817
Five acres washed away in a single storm ( Barber, 2001). At this time there were salt pans where the Shutterton Brook met the estuary.

1824 - Gap in Outer Bank
The "Great Gale". Extreme hurricane; see the Chesil Beach Storm and Hurricane webpage for details. The hurricane was accompanied by a high storm surge. A gap was made in the outer bank of Dawlish Warren in 1824, presumably by this great storm. It was recorded by Martin (1872 and 1876 - Transactions of the Devon Association, vol. 5, 1872, pp. 84-89, and vol. 8, 1876, pp. 453-460.)

1844 - The warren extended to 300 acres, and there was a saltworks "in the heart of the dunes" ( Barber, 2001).

1846
The South Devon Railway line extended from Exeter through Dawlish Warren and Langstone Rock to Dawlish and Teignmouth. It was constructed by Isambard Kingdom Brunel after previous surveys. A deep and narrow cutting took it through the Langstone Point headland. Subsequently this cutting has been much widened to reduce the curvature of the track that the headland has now become 'Langstone Rock' ( (Kay, 1990).

1869
In 1867 the Exe Bight Oyster Fishing and Pier Company laid down 30,000 oysters in beds in Greenland Lake. In 1869 a storm ripped throught the Warren and the displaced sands were dumped on top of the oysters ( Barber, 2001).

Also in 1869 (Peacock (1869) predicted the ultimate doom of the Warren and its replacement by "a dangerous bay of shoals".

1872 - Gap in Outer Bank now Enlarged
The gap in the outer bank was now a furlong wide (approximately 201 metres). See Martin and Ussher (1913). The sea had repaired the breach by 1898.

1892
Formation of the golf course on Dawlish Warren ( Barber, 2001).

1899 - The first of the bungalows was built at the Exmouth end of the Spit ( Barber, 2001).

1900
Bungalow development on the Outer Warren continued, but there were soon problems with coast erosion and bungalows had to be moved or were destroyed by the sea.

1902 - Saturday 8th November.
There was a violent storm at Plymouth and it was bad elsewhere in Devon with very heavy rain. There was sheet-flooding on NW Dartmoor. In gusts the wind reached 86 miles per hour at Smeaton Tower on Plymouth Hoe, a record. Between gusts the speed was 50 mph. The wind was from SSW veering to West. "From seven until ten the gale at Starcross raged with great violence and rain fell heavily. .. Fortunately it was nearly neap tide. Had it been spring tide Starcross and those houses facing the river would have been swamped. As it was the waves dashed over the jetty and against the railway banks, and the wind catching the spray carried it along in blinding sheets." ... "Just about ten o'clock the wind veered [from SW] to W. and N.W., and in an almost incredible time the river was as unruffled as a millpond. Those who live close to the river can hardly remember such a sudden change. At the same time an unusual sight was noticed - the waves in the Channel could be seen rising high above the [Dawlish] Warren Sand hills."

1908-1909 - Geological Map

1911
11 December, Saturday night and Sunday morning. Eighty mile an hour winds drove huge waves onto Dawlish Warren. Much destruction. The sea cut away, in many places, the banks of sand and wiregrass and made channels through from the sea shore to the little bay, which at high tide, divides the popular side of the Warren from the golf course. Bungalow destruction at the Outer Warren ( Barber, 2001).

1905
Warren Halt opened as an unstaffed halt at the Warren (not then known as Dawlish Warren) (Kay, 1991)

1912
Warren Halt was replaced by a new station a quarter of a mile to the north. The Great Western Railway named this "Dawlish Warren". Subsequently the peninsula took this name from the station (Kay, 1991).

1913
Storm damage and loss of bungalows of the Outer Warren (Kay, 1991).

1949-1962 - Peak Erosion.
Erosion reached a 'peak' of about 7m. per annum loss for the central part of the beach of on the outer Warren ( Kidson, 1964). The long-term average recession had been much less - about 1 metre per annum.

1950 - Prediction of 15 year life.
Kidson (1950) forecast a life of ten to fifteen years for the Outer Warren, in the absence of major defence works.

1962
New rock armour (larvikite) was added to the granite rock armour at the southwestern part of Dawlish Warren.

1963-4
There was a breach of the Warren and loss of sand. As a consequence series of timber groynes and gabion basket revetments were installed and maintained by the Environment Agency.

1963-4
In 1971 major works were commence by the Water Authority to help stabilise Dawlish Warren. These were completed in 1974 (Great Cliff, 2006).

1971.
Major works commence by the Water Authority to help stabilise Dawlish Warren.

1974.
A large section of Dawlish down platform was demolished by a storm on 11th February 1974. Work was completed on stabilising the Dawlish Warren area.

2008.
Problems with the coastal railway being affected by storms. BBC News. 2008. Sea level rise means rail rethink..
Fears about sea level rises swamping the existing main railway route to the South West mean the old line between Okehampton and Plymouth may be revived. The current line runs along Dawlish seafront and trains can be cancelled and delayed during heavy storms as waves break over the line. Long-term concerns about the line mean that the inland route, closed in the 1960s, may have to be reopened. A report for train operators says it could happen within the next 50 years.

2008 - more
Can Dawlish Warren be Saved? (10th January, 2008)
See the full version by going to link above. A summarised extract of the text is in the references below:
Can Dawlish Warren be saved? By Laura Joint.
The speeding up of coastal erosion at Dawlish Warren has raised concerns over the future of its famous beach and nature reserve. The main railway line and coastal properties might be at risk, too. The sands of time could be running out for one of Devon's best loved beaches. Dawlish Warren in South Devon is being eroded at an increasing rate - raising fears for the beach, the national nature reserve, main line railway and people's homes. Sections of the famous golden sands at Dawlish Warren beach have washed away - literally. Meanwhile, on the other side of the River Exe estuary, there appears to be more sand on Exmouth beach, and one theory is that Dawlish Warren's loss is Exmouth's gain... continues.

2010
Beach Facing Uncertain Future. The Western Morning News. Thursday, March 18, 2010. See the original article.
"Fears are growing that 3 million pounds of funding to save a popular West country beach from being washed away will come through too late. Teignbridge District Council says Dawlish Warren, on Devon's south coast, has seen "dramatic losses" in the last year, with a single storm removing around 10 metres of dune frontage and reducing the beach level by more than a metre. Erosion of the beach – a magnet for around 10,000 visitors a day at the height of the season – has long been a concern as coastal currents sweep the sand to the rival resort at Exmouth. While the Environment Agency is carrying out emergency work at the beach, further funding to "recharge" the beach could be "quite a long way off". Council leader Alan Connett questioned whether enough was being done to prevent the Warren from "over-topping"....continues [go to reference list below for more information]

2010 more
Isle of Wight sand could replenish Devon beach . BBC News, 18th March 2010. A summary of the text follows:
Dawlish Warren. The Environment Agency is already protecting dunes. Sand could be brought in from the Isle of Wight to replenish stocks at a Devon beach. Dawlish Warren has lost tonnes of sand during storms, with the beach level reducing by 1m (3ft). The council is now bidding for a 3m pound project by the Environment Agency (EA) to bring the sand back. The funding request is on the EA's approval list but more work is needed to assess the full cost benefits before final approval, said a spokesman. The agency is already carrying out 110,000 pounds emergency works to protect the stability of the dunes and flood defences at the Warren. Councillor Alan Connett, leader of Teignbridge District Council, said: "We need the Environment Agency to spend some real money to restore the beach, because the risk is if there's another bad storm, the Warren could be overrun." Geoff Wills, Mayor of Dawlish said: "Sand is vitally important for the tourism of the area. They come in the droves to see the sand and play on the sand."

DAWLISH WARREN:

Future Prospects

It is unfortunate that the future for Dawlish Warren, with regard sea-flooding and coast erosion, does not seem very promising. Gloomy predictions have been made in publications since 1869 (Peacock, 1869) and appeared in print again in 1950 (Kidson, 1950). There has been continuing concern more recently. There are sea-defence works of various types and they give some degree of protection to Dawlish Warren (especially the landward, southwestern part), much of it is likely to be destroyed by the sea in coming years. This is because of rise in sea-level, and prospects of more frequent storms, as a result of global warming.

There are several reasons for expecting major flooding or flood damage at some future date. Dawlish Warren is a very low sand bank, much of it only a few metres above sea level. Its bedrock base is, for the most part more than 20 metres below sea level and it is situated on buried channels of the river Exe ( (Durrance, 1980). There is no solid bedrock support near sea-level. Unfortunately, it has a bad history of coast erosion and not much of the original spit is left (see maps above). Many of the early buildings, chalets and bungalows, have been destroyed, although it should be noted that these were at the distal end. The far part is particularly likely to change and is affected by currents in addition to wave action.

Dawlish Warren has already had much sea defence constuction and alteration. Emergency work was undertakne by the Water Authority in 1971. Greenland Lake has been filled in. Although gabions extend along the spit, more resistant sea defences of rock armour are only present at the southwestern part of the shore.

A recent problem is the rate of relative sea-level rise on the south coast of England has roughly doubled since the 1940s. In the Southampton area it is now about 4mm per annum, compared to 1 to 2 mm per annum in the past. A further potential problem is that the 1 in 250 year hurricane (e.g. the 1824 Great Gale and the 1703 Daniel Defoe Storm) will occur again sooner or later. The rare but extremely severe, English Channel hurricane can produce storm surges of 3 metres or more above high tide level. This would swamp most of Dawlish Warren. It would not necessarily totally destroy it as a physical feature. The damage, however, would be substantial.

Future natural repair is unlikely in the short term because there is no large stock of sand on the east side, the source area for longshore drift (southwest to northeast). Brunel's railway and sea wall have cut off the supply since 1846. It is probable that Dawlish Warren has been formed naturally in large part from supplies of sand that came by erosion from the Dawlish cliffs. The problems of the area are well-recognised. There have been statements in the press that the railway line from Dawlish Warren to Dawlish is threatened by rising sea level. It may have to be abandoned within 50 years and there is discussion in progress about future use of an inland railway line to the west.

DAWLISH WARREN:

More on the Erosion Threat

See the following article in the BBC Homepage - Nature section.

Can Dawlish Warren be Saved? (10th January, 2008)

See the full version by going to link above. A summarised extract of the text follows:

Can Dawlish Warren be saved? By Laura Joint.

The speeding up of coastal erosion at Dawlish Warren has raised concerns over the future of its famous beach and nature reserve. The main railway line and coastal properties might be at risk, too. The sands of time could be running out for one of Devon's best loved beaches. Dawlish Warren in South Devon is being eroded at an increasing rate - raising fears for the beach, the national nature reserve, main line railway and people's homes. Sections of the famous golden sands at Dawlish Warren beach have washed away - literally. Meanwhile, on the other side of the River Exe estuary, there appears to be more sand on Exmouth beach, and one theory is that Dawlish Warren's loss is Exmouth's gain.
The estuary habitat at the warren's Site of Special Scientific Interest - home to a wide array of wading birds - is also being eroded. If the erosion continues, the main railway line will be at risk, as well as properties. The Government's environment department, Defra, has funded an investigation into the problem and a report is being drawn up by a group of organisations including the local district councils, the Environment Agency, Natural England and Network Rail. Teignbridge District Council is worried that the loss of sand at Dawlish will hit the tourism industry and local economy - a fear echoed by traders in the town. The Environment Agency deals with the threat of flooding, while Natural England is responsible for managing the nature reserve. Chris Davis of Natural England (formerly English Nature) said the Exe Estuary is a complex area and there are no 'quick fixes' to the issue of erosion. "It's a fascinating site as it is very dynamic. It moves around, and the sediment moves around as well. We have to work with it, rather than against it. We are working on a plan which is a sustainable solution." As part of the study, the agencies are looking at past changes in the estuary to assess if this is cyclical. Mr Davis said: "Erosion in this area isn't a new problem, but it has speeded up in recent years. The agencies have drawn up a plan to address the threat of any catastrophic event happening while the detailed investigation into a long term sustainable solution is ongoing. It would be a knee-jerk reaction to build up defences there now." Mr Davis said that all options are being considered - including letting nature take its course. However, he said that all interests are being considered...... -- The results of the study and details of a long-term solution are expected to be revealed in the summer of 2008. That will be followed by a period of public consultation.

DISCUSSION

More Rock Armour Protection

The spit of Dawlish Warren already has sea defences in part, but they are only substantial at the southwestern end. Old granite rock armour has been placed near the railway, and newer larvikite rock has been brought in by barge to form an extension of this. If it was possible to add rock armour on a large scale so as to form a high wall all round the margins of the sand spit on both seaward and estuary sides then the long term survival may well be much increased. However, this would damage the pleasant sandy beaches.

Perhaps, sand from offshore sand banks could be pumped into the central area to raise the land level, but interfering with the offshore banks might cause further problems.

The problem of supplies of rock armour (or rock armor or armourock) is likely to be a more general problem in the future. Firstly, it will be less easy to purchase in a financial recession. Secondly, the greenhouse gas effect of moving rock from Norway (i.e. larvikite from Larvik near Oslo) might be regarded as undesirable in the future. Thirdly, there may be very heavy demand for rock armour elsewhere, particularly to protect the low, east coast of England as sea level rises.

It is true that local sources of hard rock are available in Devon and Cornwall. Dartmoor granite has been used in the past for rock armour, and it is an igneous rock not very different from larvikite (both are types of monzonite, but larvikite has lower Si). It would probably be very undesirable from an environmental point of view to have a "superquarry" in southwest England supplying granite to protect the Devon coast, but this might be considered in the long-term future. Masses of rock armour are much more likely to be used in front of highly developed urban areas, though, rather than at nature reserves like Dawlish Warren.

To discover more about the sea-flooding risk in the region consult the Environment Agency flood maps. These will show the location of sites liable to flooding.

DISCUSSION:

Discussion in 2010 about Dawlish Warren and Possible Import of Sand.

Beach Facing Uncertain Future. The Western Morning News. Thursday, March 18, 2010. See the original article. A condensed text follows:

"Fears are growing that 3 million pounds of funding to save a popular West country beach from being washed away will come through too late. Teignbridge District Council says Dawlish Warren, on Devon's south coast, has seen "dramatic losses" in the last year, with a single storm removing around 10 metres of dune frontage and reducing the beach level by more than a metre. Erosion of the beach - a magnet for around 10,000 visitors a day at the height of the season - has long been a concern as coastal currents sweep the sand to the rival resort at Exmouth. While the Environment Agency is carrying out emergency work at the beach, further funding to "recharge" the beach could be "quite a long way off". Council leader Alan Connett questioned whether enough was being done to prevent the Warren from "over-topping". He said: "I was shocked to see just how much sand has been lost from the Warren when I walked along the front. "I am told that storms since the start of the year have resulted in the loss of more sand. "The Warren has national and international designations for its wildlife and the way the sand is being eaten away must be a very real worry to the Environment Agency." The agency has confirmed it is in the process of trying to get 2.9 million pounds funding from the Department for Environment, Farming and Rural Affairs (Defra) for a beach recharge scheme. While the funding submission sits on the Environment Agency's "sanctioned" list waiting for approval, more work has to be done to assess the economic value of committing the public funding. The bid has to be put before technical specialists on the agency's National Review Group before it can be approved. The whole process could take two to three years. In the meantime, the Environment Agency has committed 110,000 pounds for emergency works to be carried out to protect the stability of the dunes and flood defences. The money has bought block stone and hardwood timber to repair and protect the dunes and groyne structures. A spokesman for the Environment Agency said the emergency work would be completed by May this year. He said: "Clearly we are taking the precautions needed at Dawlish Warren very seriously. "The amount of money that is needed that Coun Connell refers to is nearly 3 million pounds. "That has to go through a strict process. That's quite a long way off." Some blame the beach's precarious state on the closure of Exmouth docks in the 1980s, which ended dredging of the Exe. Criticism has also been levelled at the Environment Agency for not promptly replacing the wooden groynes that line and protect the beach from the sea. To the chagrin of the tourism industry, countryside quango Natural England has suggested the Warren, part of which is also a protected nature reserve, should be left to revert back to a "natural state"

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See also:

Isle of Wight sand could replenish Devon beach. BBC News, 18th March 2010. A summary of the text follows:

Dawlish Warren. The Environment Agency is already protecting dunes. Sand could be brought in from the Isle of Wight to replenish stocks at a Devon beach. Dawlish Warren has lost tonnes of sand during storms, with the beach level reducing by 1m (3ft). The council is now bidding for a 3m pound project by the Environment Agency (EA) to bring the sand back. The funding request is on the EA's approval list but more work is needed to assess the full cost benefits before final approval, said a spokesman. The agency is already carrying out 110,000 pounds emergency works to protect the stability of the dunes and flood defences at the Warren. Councillor Alan Connett, leader of Teignbridge District Council, said: "We need the Environment Agency to spend some real money to restore the beach, because the risk is if there's another bad storm, the Warren could be overrun." Geoff Wills, Mayor of Dawlish said: "Sand is vitally important for the tourism of the area. They come in the droves to see the sand and play on the sand."

MISCELLANEOUS TOPICS:

Uranium in the Exmouth and Langstone Rock Area

An investigation of radon in stream water by Durrance (1980) resulted in the map shown above. There is a remarkable concentration around the mouth of the Exe Estuary. The content is higher here (but not dangerous) than even in the area of the famous radioactive nodules of Littleham Cove, near Budleigh Salterton (east of the Exe Estuary).

The distribution has not been explained. An underground accumulation of radioactive minerals such as uranium minerals is needed to account for this. The possibilities are as follows:

1. The presence of veins of uranium ore (pitchblende) like those associated with the granites of southwest England occurring in the Langstone-Exmouth area.
- unlikely (such an occurrence would have to be very deep, because the appropriate strata (Devonian, Carboniferous) are only at great depth).

2. The Permian breccias, such as the Langstone breccia contain some uranium minerals, either in the clasts (fragments) or in the associated sand.
- quite likely, but unproven.

3. There is some process of concentration of mineral grains derived from Dartmoor in the beach sands or in Pleistocene gravels of the area of the mouth of the Exe Estuary.
- less likely, but not impossible

4. The radioactive nodules of the Littleham Cove Mudstones of Littleham Cove represent an example of a type of sedimentary uranium deposit that is better developed in (older) Permian, playa lake deposits, somewhere underground near the mouth of the Exe Estuary.
- possible (with remote possibility of economic uranium deposits in the area)

At the moment the answer to this mystery does not seem to be known.

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