Barrier beaches of the Atlantic coast

by Frederick J. H. Merrill

Besides these alterations produced in the beaches by their westward progress, the variations in the positions of the inlets and the subsidence of the coast have caused many important changes. The history of the Shrewsbury Inlets has already been given; it remains to mention a few of those south of Point Pleasant.

Squan and Island Beaches, which now form a peninsula about twenty miles long, terminating at Barnegat Inlet, were separated from 1750 to 1812 by Cranberry Inlet, which was nearly opposite the mouth of Tom’s River. Since 1812 near the site of this old inlet there have been others of brief duration, and one is said to have existed before 1755 opposite the mouth of the Metedeconk River, which separated Squan Beach from the mainland.

The old Barnegat Lighthouse is said to have stood nearly six hundred yards north of the present south shore of the inlet, at a point now occupied by the center of the channel. In 1855 the old tower was at the water’s edge, so that the inlet has moved southward approximately twenty yards per year.

Absecon Inlet, which separates Brigantine Beach from Absecon Beach, has encroached upon the latter about four hundred yards in twenty years; and the ocean front of that portion of Absecon Beach which is occupied by Atlantic City extended in 1855 nearly half a mile farther east than it did in 1885. About 1875 jetties were built which arrested the action of the tidal currents, and, the wear of the shore being thus prevented, a considerable area was restored.

Submerged tree-stumps and other evidences of a subsidence of the coast may be found on the beaches and the salt meadows, but a detailed enumeration of them would be beyond the scope of the present article.

In Cape May County the depression has not been less than twenty feet, and has possibly been much greater. The evidence of some old buildings on the shore of Delaware Bay suggests a subsidence of about four feet during the last two centuries.

It is doubtful whether depression alone has caused the wear of the coast. A comparison of the present outline of Holly Beach with that determined by a survey in 1772 shows an accretion on the south and east, since the latter date, more than three and a half miles long and averaging three eighths of a mile in width, and on many other beaches a similar growth has taken place. During the past five years the ocean has rapidly encroached upon these beaches, while the subsidence of the coast, so far as we know, has been uniform throughout the past two centuries. It would appear, therefore, that the growth and decay of the beaches are more dependent upon the action of the ocean currents and winds than upon other agencies. Unquestionably the depression of the coast renders the beaches more subject to overflow and erosion by the waves and currents; but the evidence at many points shows that the latter are capable of forming large areas of beach where the conditions of their existence and action favor construction rather than destruction. While these currents act as at present, the cost of preventing the ravages of the sea, by the methods commonly in use, would probably be much greater than the value of the land protected, for the fine sand is so unstable when wet that bulkheads and breakwaters are quite ephemeral.

After an extended examination of the various systems of shore defense in use between Sandy Hook and Cape May, it appears to the writer that the only effectual means of protection is the construction of jetties extending far enough from the shore to intercept the currents which carry away the sand loosened by the waves. Such jetties have added a large area to the territory of Atlantic City, and have protected the shore at Cape May; no doubt they would be effective everywhere if properly constructed.

The experience of the past ten years on the New Jersey coast shows conclusively that the ocean front is not fit for building purposes, for it is impossible to protect a house near the water’s edge from injury or destruction in the heaviest storms. The height and force of the waves in such a tempest as that of September 10 and 11, 1889, render them irresistible to any body or structure which nature or art has yet produced, and anything within their reach must suffer. The immediate water-front is only available for parks; and, if devoted to this use, when protected from the erosive action of the currents by suitable jetties, would remain a neutral ground which, in fair weather, would afford numberless attractions to the occupants of dwellings placed far enough from the strand to be out of reach of the storm-waves.

Property-owners along the ocean front of the beaches have generally made the mistake of supposing that the domain of the Atlantic was bounded by the high-water mark of the spring tides. Any one who should build a dwelling on the strand below ordinary high-water mark would be considered lacking in common sense, yet it is scarcely less foolish to build within reach of the storm-waves. It is, of course, true that many cottages are now much nearer the water’s edge than they were a few years ago. This is due to the wear of the shore by currents already described as flowing parallel to it and removing the sand which the waves have loosened. If the action of these currents should be stopped—and there is good evidence to show that a system of jetties would intercept them and cause them to drop their stolen load of sand—the wear of the shore would be arrested and the yearly encroachments of the ocean would cease.