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The harbor of refuge at Block Island, which is entirely an artificial harbor, is at the southern end of the curve which forms the eastern side of the island. Be. fore its construction Block Island had no harbor. The only vessels used were open boats, which on the approach of storms were hauled up on the beach by
The largest of these boats were of about 10 tons burden. The works consisted of a main breakwater, which extends northerly from the shore, a distance of about 1,900 feet, forming the outer harbor, and the inner harbor or basin referred to in the resolution of the Senate.
The inner harbor lies in the western angle between the breakwater and the shore. It is about 300 feet by 250 feet in area and has an opening about 80 feet wide (60 feet in tbe clear), on the north side, through which vessels pass to and from the outer harbor.
It was first dredged to a depth of 7 feet at mean low water. Afterwards it was dredged to a depth of 9 feet, and the bottom of a large part of the outer harbor was cleared of bowlders.
The main breakwater, except for a distance of about 300 feet from the shore, where it forms the eastern side of the inner harbor, is constructed of riprap gran. ite. It is 35 feet wide at the top, which is 6 feet above mean high water. The ipper slope is 1 on 1 and the outer slope is 1 on 2.
The eastern, northern, and western sides of the inner harbor are of crib-work constructed in 1871–72) of spruce timber, resting at about the level of low water, on a riprap foundation, and filled with stones gathered on the island.
The crib-work on the eastern side, which is most exposed to the force of the waves, became so much decayed that an interior wall of masonry was constructed during the last year to protect the inner harbor when the crib-work on that side is carried away by the sea.
The crib-work on the two other water sides of the inner harbor is also very much decayed, and will soon be liable to destruction in heavy storms.
A plat exhibiting the bottom of the outer harbor as it was found by the survey of 1878, and also by the survey which I caused to be made last August, shows that there was much shoaling—3 feet in some places-between the times of the two surveys.
The material used for this shoaling comes from the high cliffs at the southward and eastward of the harbor, which are constantly being undermined by the sea, and also from the shore, which extends from the harbor to the northward and westward.
The former material is carried along outside the main breakwater, a part of it passing through the interstices of the riprap forming a parallel bank inside, which does not encroach much upon the anchorage.
Another portion passes through the gap in the main breakwater, and is doubtless afterwards brought farther into the outer harbor in northerly storms, causing a general shoaling of the harbor.
After the closing of the gap, which is to be done by means of the appropriation of July 5, 1884, some material will probably pass around the outer end of the main breakwater and be carried into the outer harbor as before.
The quantity of material which comes from the shore to the northward and westward of the harbor is very large, as is shown by the great amount of filling in the angle between this shore and the harbor works.
UTILITY OF THE INNER HARBOR.
The eastern shore of Block Island, on which the harbor of refuge is situated, is exposed to the full force of the waves of the Atlantic. In northerly storms especially, small vessels cannot lie with safety in the outer harbor, and even in northeasterly and easterly storms the swell which makes round the extremity of the main breakwater is so heavy that none except large vessels will remain outside, unless for want of room they cannot get into the inner harbor -which although made for the temporary purpose of sheltering the vessels that carried stone from the mainland for the main breakwater in the earlier periods of its construction, has proved one of the most beneficial works in my district. At night, especially in bad weather, it is always filled to its full capacity.
On a recent visit to Block Island I counted fifty-nine fishing and other vessels crowded into this little area, and larger numbers would have availed themselves of the complete shelter which it affords, except for the want of room.
Appended to this report, I send a copy of a letter containing the statistics of the use of the inner harbor during the last year, which have kindly been furnished by the Hon. Nicholas Ball, a prominent citizen of Block Island, at my request.
These statistics confirm the judgmeut derived from my own observation, that the size of this excellent refuge is entirely inadequate to the requirements of local and coasting vessels, and that it would not be good policy to replace by masonry walls the decayed crib-work, retaining the present size of the inner harbor.
I intended to submit these views to the Chief of Engineers in my next annual report, and I am gratified at this earlier opportunity, furnished by the Senate resolution, of stating that, in my judgment, the enlargement of the inner harbor is a public necessity, and of submitting the following plan for it:
PROPOSED ENLARGEMENT OF THE INNER HARBOR.
From the shore west of the inner harbor, and at a distance of about 1,000 feet from it (1,300 feet from the prolongation of the line of the main breakwater), there is an old jetty which was constructed upon a bowlder reef which projected from the shore at this point and extends out to about 300 feet from the highwater line. This jetty, which was built of rounded bowlders found on the island, had not much stability, and has become much flattened down by the sea.
I propose to build up on this jetty, and to extend it about 200 feet on a line parallel to and distant about 950 feet from the main breakwater; thence the western part of the proposed inner breakwater follows an arc of 90 degrees with a radius of 150 feet, and connects with the northern part which is on a line run. ning at right angles with the main breakwater, and intersecting it at a point about 650 feet from the outside of the crib-work forming the north side of the present inner harbor, or about 950 feet from the Government wharf on the south side of this harbor.
The inner breakwater is to be constructed of granite riprap 4 feet wide on the top, which is to be 5 feet above mean high water. The western part to have side slopes of 1 on 1, the northern part to have a slope of 1 on 1 on the inside, and a slope of 1 on 1} on the outside. The shore end of the western part above the lowwater line is to be constructed of crib-work filled with stone.
At a distance of 150 feet from the main breakwater, or, more exactly, 150 feet from the 6-foot curve of the submerged bank on the inside of this breakwater, I propose to leave in the inner breakwater an opening, on each side of which there is to be constructed a pier-head of dry masonry, protected by fender piles in the usual manner, leaving the opening 100 feet wide in the clear.
The northern part of the inner breakwater, which is on the most exposed side, should be built first. This would allow us to remove the crib-work which forms the northern side and a part of the western side of the present inner harbor, and to use the stone filling and foundation-say 4000 tons-on the western side of the enlarged harbor.
The area of the present inner harbor is about 14 acres. The area of the proposed harbor, inclosed between the low-water line on the shore and the inner breakwater, is about 184 acres. About 5 acres are inclosed within the curve of 9 feet at mean-low water, 94 acres within the 6-foot curve, and 15 acres within the 3-foot curve.
Experience has shown that the depth gained by dredging in the present inner harbor is permanent, and it will doubtless be found that the shoaling of that part of the outer harbor which it is proposed to include within the new works will be stopped, since the littoral sands now brought in by the waves from the westward, and the sands which are now brought in through the gap in the main breakwater, and which, when it is closed, may be brought in around its extremi. ty, will be arrested; the former by the western part and the latter by the northern part of the proposed inner breakwater.
It is probable that, for the purpose of sheltering the larger class of vessels in the outer harbor in northerly and northeasterly storms, and of quieting the water in that harbor in all storms from the eastward, it may be found necessary at some time in the future to extend the main breakwater in a westerly direction 1,000 or 1,200 feet, or to such distance as may be desired, leaving an opening between it and the present head of the breakwater.
The area of the enlarged inner harbor for small vessels (nearly all of the vegsels which now use the harbor of refuge at Block Island are of this class) is not as large as I would have proposed, except that I do not wish to encroach so much on the area of the outer harbor as to impair its usefulness for large vessels, the number of which seeking refuge at Block Island is likely to increase, especially in case the main breakwater is extended as above mentioned.
If deemed desirable, however, when we come to the construction we can make the northern part of the inner breakwater on a line 100 or 200 feet further north with but little increase of expense.
The Government wharf, which occupies the land side of the present inner harbor, is the only wharf at Block Island, except a private wharf which was built some years since outside the inner harbor and on the inside of the main breakwater, by permission of the Secretary of War. The latter wharf is used only in summer, and by steamers which carry visitors and excursionists from and to the mainland. The Government wharf is always overcrowded with the traffic of the island. All the freight carried to and from the island is brought here, and at it are landed the United States mails and the supplies for the four light-houses, which are on the island, and the steam fog signal.
The enlargement of the inner harbor will allow additional private wharves to be built within it, and thus relieve the Government wharf, but the building of such wharves should only be by authority of the Secretary of War and under such conditions as may be prescribed by him.
In the following estimate of the cost of the proposed enlargement I have not included any dredging of the area proposed to be included within the inner harbor. None will be necessary in the first instance, and when it becomes so it can be done gradually and as the wants of the harbor_may require. As before suggested, any additional depth which may be gained by dredging in the enlarged uner harbor will be permanent.
ESTIMATED COST OF THE PROPOSED ENLARGEMENT.
21,120 tons of riprap granite, at $1.65 per ton.....
the present inner harbor to the proposed inner breakwater, at 50 cts.
Breaking up and removing the old cribs....
the western part of the proposed inner breakwater....
the new harbor, at $11 per cubic yard... Fenders and dolphins at entrance.
Add 10 per cent. for contingencies...
Total estimated cost.....
$46, 189 Very respectfully, your obedient servant,
GEORGE H. ELLIOT,
Lieut. Col. of Engineers. Brig. Gen. JOHN NEWTON,
Chief of Engineers, U. 8. A.
LETTER OF HON. NICHOLAS BALI..
BLOCK ISLAND, R. I., December 16, 1884. My Dear Sir: Yours of the 13th, in which you ask for the statistics of the use by vessels of the inner harbor or basin during the last few years, and especially during the last year, was received on Saturday,
In reply would inform you that on its receipt I at once sought an interview with Mr. Uriah Dodge, who keeps the range-lights here, and also with my son, C. C. Ball, who keeps the store here, both of whom have more or less to do with the boats and vessels which frequent the harbor.
There is no record kept by any one of the arrival and departure of vessels, hence I could gather nothing authentic, more than I have got together in a report which I inclose, which, in my opinion, is not far out of the way, and which I hope and trust will answer your purposes. The report may be considered as that of the past year; the three previous years on an average. say 20 per cent. less.
Mr. Dodge, the light-house keeper, says that thirty-five boats and small vessels fill the basin full enough, especially in bad weather.
He further says:
The general stock of swordfish here last season, at a rough estimate,
is about .....
10,000 18,000 8,000
800 5,000 11,500