15 December 2014

British Rail weakest link : Dawlish.

Ongoing repairs to the breached sea wall.

Defending Britains railways against extremes of weather is no more contensious than here at Dawlish where recent breaches have been widely reported during past months.

Storms, floods, extreme weather and cliff erosion.

Early memories of the beach-front include seeing numerous beach huts immediately fronting the Dawlish railway station, where the levels of beach were above the high water mark. During my lifetime a lowering of the beach has occurred of about 14 feet along this section between the main breakwater and the coastguards breakwater. Further along towards Dawlish Warren an even greater loss has been seen, especially between Coastguards and Black Bridge, including the section where the Rail line was  recently breached.

Exmouth in the distance behind Langstone Rock

Before the line was ever built, cliff erosion would have continuously replenished beach material and established the sand and shingle at a fairly constant level, but since the 1841 rail line between Dawlish Warren and Teignmouth  has been here, falls into the sea of cliff face debris has ceased. The very much reduced supply of sand has been in an easterly direction from the Teignmouth Estuary and Labrador Bay, where cliff falls onto the foreshore still occurs. Only lately interrupted due to dredging of the estuary mouth.

Dawlish Warren has fluctuated widely over this time span and Exmouth beach has seen marked gains as the sand gradually drifts eastwards, due to wind and tide (long-shore drift).

In the 1970s much was done to alleviate losses by establishing sea defences along the dunes and railway frontage between Langstone Rock and the Warren point extremity. This involved approximately twenty substantial hardwood (Greenheart) groins and a continuous line of gabbions above high water mark (since covered over by a line of sand dunes).

At Black Bridge beach has disappeared and washed towards Exmouth

The completion of the rail line by I.K. Brunel included the building of multiple wood groins where vertical iron posts driven deep into the sand kept heavy timbers in place. Lengths of iron rail being used and bolted through. 

Years without maintenance have seen these early structures worn away and only a few vestige remnants are to be seen today. Such a pitiful neglect of one of I.K.Brunel's most spectacular feats of civil engineering.

Concerns have been expressed about the future of Dawlish Warren erosion and the loss of wildlife habitat.

The Environment Agency is involved, The Council for the Preservation of Rural England is involved.  South west Water and the local Teignbridge Council is also involved.

The link here to extensive studies by Southampton University, already completed, contains much of interest relevant to the coastal sea defences between Dawlish and Teignmouth. 

Here was once beach sand and pebbles

There are effective solutions to sea erosion already in place at Sidmouth and at part of the rail link close to Langstone Rock, which protects to good effect Dawlish Warren and its Nature Reserve.  However such full measures have not been utilised at Dawlish so leaving the line vulnerable to rough seas.

Overlooked, is the level of beach foreshore that would, if raised, largely absorb the waves' destructive power, before it meets with the vertical walls of the rail line. Today's low beach level permits the largest of waves to batter the wall with full destructive power.

The problem is one of funding and choice - whether to preserve the line or let it deteriorate further.  Coastal erosion, if left unchecked, will no longer permit safe travel along this section of line. Much funding money is supposedly "set aside", whatever that means. 

A small percentage has been spent on repairs. Politicians made their photo calls standing on the Dawlish Station platform, but memories fade and votes are amassed by more expedient means than provision of maintenance programmes to the far south west of Westminster.

Footings placed in recent years

To replenish beach levels a large quantity of sand and rock is required, totalling something in the region of  7.5 million tons. In addition, the breakwaters as seen at Sidmouth should be deployed at Dawlish so that foreshore it is not so easily lost to long-shore drift.

A sum in excess of £8 million has been earmarked for the replenishment of beach at Dawlish Warren BUT NO SUCH PROVISION has yet been planned for preserving beach levels along the railway fronting Dawlish.

The first giant scoops of almost 5m tonnes of earth from deep beneath London have been delivered to the Essex coast, the first step in creating the biggest man made nature reserve in Europe.
The soil, excavated from two 21 kilometer tunnels under the capital, will transform the pancake-flat intensive farmland of Wallasea Island into a labyrinth of mudflats, saltmarshes and lagoons last seen on the site 400 years ago.
The RSPB hopes the new reserve will see the return to England of lost breeding populations of spoonbills and Kentish plovers, as well as increasing already internationally important flocks of avocet, dunlin, redshank and lapwing, along with brent geese, wigeon and curlew in winter.

The cost of Crossrail £14.8 billion or £14,800,000,000  counting all the noughts.

The £8 million earmarked but not yet spent on Dawlish Warren is a paltry 0.054% of the projected cost of London's Crossrail.

Meanwhile the South West Line suffers from lack of protection from the waves at Dawlish.

A few iron posts remain of earlier groins

Looking eastwards this beach will be mostly covered at high tide. Longshore drift carries towards Langstone Rock

From here towards Dawlish Station beach level reduction is most noticeable.

The crane here seen working at ongoing repairs at Sea Lawn where the breach occurred.

No access is permitted through that area at present. (17-12-2014)

View towards Langstone Rock, Dawlish Warren and beyond to Exmouth

Severe losses from Dawlish beach between Coastguards and Langstone Rock (Exposed sewage pipe and remains of groins.

Sidmouth showing three of the stone breakwaters and debris from the same storm that damaged Dawlish Rail line.

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