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and there are here situated a greater number of seaside resorts requiring protection than in any other part of the coast.
The coast-line is almost straight, and is free from any deep indents or embayments, and up to Brighton, a distance of 30 miles, is more or less bordered by cliffs consisting of clay and sand, only a few feet in height, which are constantly being eroded by the sea in gales, but which afford very little supply of beach material.
Throughout there is a more or less continuous bank of shingle of varying width, which increases to a very large accumulation at the windward or east end. This shingle was probably originally derived from the waste of the land which now forms the site of the English Channel, and from the transport of inland gravels by glacial floods.
The present conditions of the coast present no features which could account for the deposit of this shingle. On the Geological Survey Drift Map it is stated that near Selsea Bill fragments of granite, quartzite, and other stones are scattered on the shore, which would account for the pebbles from these rocks being found amongst the shingle. Chalk rocks also crop up near low water in the neighbourhood of Felpham and Lancing, but with these exceptions there is no source at any part of this coast from which any quantity of shingle can now be derived.
The shingle is almost entirely of rounded flint pebbles derived from the chalk, but amongst them are to be found, at the western end, many unworn flints having the same appearance as they would have if they had just fallen from a chalk cliff. Towards the east end the pebbles get smaller in size and more worn.
Groynes have been placed along nearly the whole of this part of the coast.
Between Brighton and Beachy Head are chalk cliffs; and at Pevensey, Dungeness, and Hythe large accumulations of shingle. The chalk cliffs begin again at Folkestone, and reach some distance beyond Dover.
Selsey and Pagham.—East of Selsey Bill is a low clay shore, the beach being slightly covered with coarse shingle, but the waves break on the low cliffs at high water. The sea has encroached considerably, upwards of 100 acres of land having been washed away within living memory. Tradition says that the village of Selsea, which now stands half a mile from the sea, was at one time in the centre of a peninsula, half of which has been swept away since the Saxon era. The site of the ancient cathedral is covered by the sea. At the time the church was built it was 2 miles to the north-east of the village, but the sea has now crept up much nearer. In the time of Henry VIII. there was a deer park, belonging to the Bishop of Chichester, which is now an anchorage ground with 3 fathoms of water, and is marked on the charts as "The Park."
Further along in the bight is a large accumulation of shingle extending for about 2 miles. The top of this bank, which is about 6 feet above high water, is from 200 to 300 yards wide, and below this the beach is covered with shingle for half a mile. This accumulation of shingle has been in its present position from time immemorial. The pebbles consist almost entirely of chalk flints of all sizes up to 9 inches in diameter. Although the greater part are rounded from having been rolled about by the waves, some are not in the least worn, but have the same appearance as if they had recently fallen from a chalk cliff. Amongst the pebbles are a few pink and brown quartzite and sandstone.
At the east end of the bight was formerly the entrance to Pagham Harbour, which is now completely closed, the land inside having been reclaimed under the powers of an Act passed in 1875. Since this reclamation, and the stoppage of the ebb and flow of the tidal water in and out of the harbour, the shingle has drifted north-eastward, and the channel, which had 40 feet of water, is now completely filled up.
From Pagham to Bognor the beach is backed by a low earthbank, which is constantly being eroded by the sea. Groynes of a similar character to those on the shore at Bognor have been placed all along the coast.
A notice-board has been fixed by the Board of Trade on the shore at Aldwick, dated 1876, stating that the removal of shingle from the beach is forbidden.
Bognor.—The coast along the whole of this frontage was originally bordered by low sandy clay cliff's, which, until protected by the sea-wall, were continually being washed away.
The beach is covered with shingle 12 to 40 yards in width, or say to about a quarter ebb tide, and below this is good firm sand resting on clay. The shingle consists principally of rounded chalk flints, varying in size from 2 up to 9 inches. At the west end, in calm weather, it reaches to within 3 feet of the top of the wall, while at the east end it is 12 feet below it.
Throughout the whole length groynes exist, which were first erected about seventy years ago. They vary in length, the longest being about 100 yards and extending nearly to low water, the others being half this length. The distance apart varies from 75 to 100 yards. They are placed at right angles to the coast-line, and near the shore, for the first 20 yards or so, are 7 to 8 feet in height, raking down to about 18 inches or 2 feet above the sand for the rest of the distance. They are constructed of fir piles 8 inches square, spaced 4 feet apart centre to centre, with 2-inch fir planking. The longer groynes cost about £60 each.
These groynes have not raised the level of the sand beach, but are efficient in keeping it level. Occasionally in heavy gales the sand is scoured out in places to a depth of two planks, or 18 inches, but it drifts back after the gales. The boatmen consider that these numerous groynes are a source of danger, small boats getting stove in occasionally in rough weather.
Between Bognor and Aldwick the roadway along the coast is held up by a timber breasting, but throughout the Bognor frontage there is a promenade protected by a sea-wall. The centre part of this wall was constructed in 1870, at a cost of £8000; and was extended eastward 240 yards in 1895, at a cost of £5000; and westward for 160 yards in 1899, at a cost of £2300. A description of the part of the wall last constructed will be found in Chapter V.
The east wall has concrete groynes extending out at right angles, and 60 yards apart. These are 3 feet wide at the top, with a batter of 3 inches to 1 foot on each side, and are stepped down. They are about 80 yards long, and cost £350 each. These have not been as effective as the wooden groynes in holding up the beach, while costing nearly six times as much. The waves, in breaking on them in rough weather, tend to cut out and denude the beach. The shingle in calm weather is from 3 to 4 feet higher on the west side of the groynes than on the east side.
During the heavy gales of the winter of 1898-99, the sea washed over the promenade and flooded part of the town, nearlv up to the High Street. With moderate waves the water from the waves falls on the promenade, especially where the beach is low.
Felpham.—Between Bognor and here a concrete sea-wall, about 3 feet thick, has at some time been constructed for the
protection of a tract of low land. This wall stands up above the land, and during heavy on-shore gales the waves break over it and inundate the land behind; a considerable quantity of shingle has also been lifted over the top and deposited on the land side by the waves. The maintenance of this wall, and of the cliffs beyond it, lias for some time been a source of anxiety to the Commissioners of the Court of Sewers of West Sussex, and they have been in treaty with Bognor for the purpose of carrying out the erection and maintenance of an efficient system of coast defence. Steps are also being taken to prevent the removal of shingle from the shore.
Beyond the sea-wall the coast is bordered by low cliffs consisting of sandy clay, which are continually being worn away. During the last two or three years more than 40 feet of the cliffs have gone, and a road and path been carried away.
Groynes have been placed on the beach at intervals of from 50 to 60 yards apart, extending out from the cliffs at right angles to the shore for 150 yards. Near the cliffs, they are from 4 to 5 feet in height, but rake down, and along the sand are only from 1 to 2 planks above the beach in calm weather. They are constructed of fir piles 4 feet apart and 2-inch planking.
The shingle-bank here is about 26 yards wide, and is similar to that at Bognor, and the sands to low water are about 330 yards wide. The groynes have been constructed several years, but the level of the sand does not appear to have been raised. It is firm and level, and free from swills and pools.
Middleton.—The coast here is of the same character as Felpham, and the low cliffs have been much eroded. The upper part of the beach is covered with a bank of shingle for about 40 yards in width; it consists of chalk flints, many of which are large, and a considerable quantity of these have been removed for facing the concrete blocks of the sea-wall at Bognor. Between here and Felpham the chalk crops out on the beach, and is visible at extreme low water, and boulders of chalk are found on the beach. No doubt it is from this source that the unworn chalk flints found amongst the shingle are derived, being drifted ashore in heavy on-shore gales.
Groynes have been in existence on the beach from here to Atherington for many years. They are spaced apart at distances varying from 30 to 60 yards, and are of similar construction to those at Felpham, and have had the same effect. They hold up the shingle next the cliff, and prevent the denudation of the sand off the clay, but have not raised the beach. They appear to have been much neglected, and allowed to get out of order.
About ten years ago some of the old groynes were repaired, and some large and more substantial groynes constructed. These consist of fir piles, reaching 10 feet above the beach, placed 5 feet apart, and boarded with 9-inch by 3-inch planks for a height of h\ feet. Two horizontal walings, 9 inches by 5 inches, are bolted to the piles, and at intervals of 15 feet are large oak ties, about 9 inches diameter and 18 feet long, placed on the windward side, and made fast to a double set of short piles. These groynes are 100 yards long, and spaced about 150 yards apart. They are placed in a south-easterly direction, at an angle bearing eastward from the shore of about 120 degrees. The planking next the shore is from 6 to 8 feet above H. W.S.T., and it rakes seaward at an angle of 1 in 16, the lower end being 10 feet below high-water level.
These high groynes are more substantially erected and higher than those at Bognor and Felpham, but do not appear to have had more effect. Since they have been erected the quantity of shingle is stated to have increased, but the bank is about the same height as that to the westward.
Littlehampton. —The coast in this neighbourhood is low. For the purpose of the harbour two piers have been constructed, which extend out across the beach for half a mile, between which the river Avon flows to sea. The west pier is boarded up nearly to high water. On the west or windward side of this are some low hills of blown sand, 100 yards in width, and from 10 to 15 feet above high water; and shingle has accumulated at the back of them for nearly half a mile in depth. On the sea side of the dunes is a small bank of shingle 20 yards wide, the top of which is above high water. The shingle consists of rounded flint pebbles, varying in size from \ inch to 5 or 6 inches in diameter, the average being about 1£ inches, a few being still angular and unworn. Seaward of the shingle to low water the beach consists of firm sand, the distance being from a quarter to a third of a mile.
The close-boarded jetty on the west side of the harbour, carried out to low water, has led to a considerable accumulation of sand, the beach extending further seaward than on the east side. It has entirely prevented any drift of the shingle eastward. Some groynes erected for the protection of the coast between the pier and Atherington are now buried.