An Essay on the Encroachments of the German Ocean Along the Norfolk Coast / With a Design to Arrest Its Further Depredations

by William Hewitt

The benefit derived from the erection of piers at the Haven’s mouth, has, in conjunction with the jetty, afforded great protection to the town of Yarmouth. The tidal wave and current has been checked, the shore has been elevated, retained, and rendered wider to the northward, as far as Winterton; [45c] a shoal of sand has formed, and extends a considerable distance into the sea, at right angles to the shore, beyond the termination of the north pier, so that it has been found necessary to place a buoy at its extremity, as a guide for the mariner to steer due east from the Haven’s Mouth to Yarmouth Roads. The jetty, extending into the sea upwards of four hundred and fifty feet, is now about to be added to, in consequence of the shallowness of the water.

The question now arises, would the jetty and piers have been so beneficial, had they not been continued into the sea to the extent alluded to? Certainly not. The shoals of sand, which formerly existed in the offing, have been removed, or rather have been converted into a solid mass; the current has been diverted from a southerly to a north-easterly direction, and the bed of the ocean nearest the shore has been elevated, and no doubt terminates into the sea upon an inclined plane.

The failure of groins, erected with pile and plank, appear to arise from their being placed in a wrong situation, from their not extending far enough into the sea, from the piles not being driven sufficiently into the beach, and from their sudden elevation, present an abrupt surface for the tidal wave to play upon, which during heavy gales of wind upon spring tides, cannot withstand its powerful effect, should the materials lying adjacent to or between them be removed. Therefore they can only be available where the interstices are completely filled with sea beach materials, and their durability must depend upon the latter cause.

CHAPTER VI.

THE RESTORATIVE POWER OF THE GERMAN OCEAN PROVED IN CERTAIN LOCALITIES.—ASSISTANCE GIVEN TO IT FROM THE STRANDING OF A VESSEL AT PURBECK, AND ON THIS COAST AT HASBOROUGH.—HILLS OF BLOWN SAND OR DUNES CONSIDERED—EXAMPLES OF THEIR STABILITY GIVEN AT WELLS, CLEY, &C., AND OF THEIR INSTABILITY AT ECCLES, PALLING, &C.—SEA-BREACH COMMISSIONERS APPOINTED.—THE ENGAGEMENT AND OPINIONS OF AN EMINENT ENGINEER IN 1804.—CONCLUDING REMARKS.

Examples of Nature endeavouring to combat with herself are shown from the immense quantity of sand, shingle, &c., brought from low to high water mark, during the summer months, and should easterly winds prevail, the sand is removed towards the cliffs, and accumulates in some situations more than in others. Thus at Walcot, [47] a deposition of sea beach materials commenced in 1839, and gradually augmented from six to eight feet in depth, within a distance of one mile and a half, and in a space comprising a few yards, it attained a perpendicularity above the cliffs, extending to high water mark, and the tidal wave, even in a northerly wind, ebbed and flowed without disturbing its surface, from the above period to November, 1843. A gale of wind then ensued from the north-west, upon a neap tide, which removed the greater part of the mound of sand, and a subsequent gale, upon a spring tide, in February, 1844, swept away the remainder.

A similar instance of accumulation was observed to have taken place on the Essex coast, commencing about the same period, and extended a distance of seven miles, which appeared in December, 1843, likely to remain. [48a]

The flat shores at Wells [48b] are considerably elevated above the depths of the ocean, into which they probably terminate in a gradual descent. The stranding of three large vessels off Winterton [48c] and Horsey, [48d] years ago, have possibly prevented its encroachments in these places.

When a vessel is stranded in shallow water, it usually becomes the nucleus of a sand-bank, as has been exemplified in several of our harbours, and this circumstance tends greatly to its preservation. Between the years 1780 and 1790, a vessel from Purbeck, laden with three hundred tons of stone, struck on a shoal off the entrance of Poole harbour, and foundered; the crew were saved, but the vessel and cargo remain to this day at the bottom.—Since that period, the shoal at the entrance of the harbour has so extended itself in a westerly direction, towards Peveril Point, in Purbeck, that the navigable channel is thrown a mile nearer that point. The cause is obvious; the tidal current deposits the sediment with which it is charged, around any object which checks its velocity. Matter also drifted along the bottom, is arrested by any obstacle, and accumulates round it, just as the African sand-winds raise a small hillock over the carcase of every dead camel exposed on the surface of the desert. [49a]

Upon the 18th day of February, in the year 1807, the Hunter cutter, [49b] during a heavy gale, struck on a shoal of sand in the offing, and finally drifted into a shallow near the shore, about a quarter of a mile to the northward of the old cart gap, at Hasborough, the stern part towards the cliff. In a very short time, sand, shingle, &c., accumulated around her, and completely filled the shallow to its utmost length. Within twelve months after, several shoals and shallows showed themselves opposite the town gap, evincing that the flowing of the tide had received a check, which proved an inconvenience to fishermen, as they had to heave their boats much farther before they could launch them into the sea; they were so aware that the Hunter cutter was the cause of this circumstance, that many a harsh expression did they utter towards her. In less than two years, more than one hundred yards could be paced from her bows on the ebbing of the tide to low water mark, and a large mound of sand accumulated between her stern and the cliff, which existed upwards of twenty years, and arrested the devastation of the sea directly opposite. From subsequent gales, however, the cliffs were taken away to the northward, the water intruded behind the mound of sand, and entirely removed it. A greater proof of the check the waves had received was observed at low water mark, a ridge of gravel was deposited and left undisturbed on the ebbing of the tide, extending from the Hunter cutter to Bacton coal gap, a distance of three miles to the northward; the first spring tide, however, swept away nearly the whole of the ridge of gravel, except that portion nearest the Hunter cutter.