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the bar from the 7 to the 18 foot curves of depth is 8,000 feet, or about 1 on 727 feet; the outer slope is also about 1 on 727 feet.

On both sides of the pass, and extending for many miles, the country is nearly flat, the average elevation of its surface being less than 2 feet above the level of mean low-water. In 1873 Major Howell, in running a line from Galveston to Sabine Pass, for a canal, reports the highest land met with at about 5 feet high, one-half a mile in width, and situated about 4 miles to the westward of Sabine Pass.

The shore line, along the coast, extending from 10 miles to the westward and nearly 200 miles to the eastward of Sabine Pass is a marshy alluvion, and forms very nearly an arc of a circle whose center is situated in the Gulf of Mexico, distant about 150 geographical miles. The 18-foot curve of depth runs nearly parallel to and is about 3 miles distant from the shore line, while the 10-fathom curve is nearly 40 miles out in the Gulf.

In 1873 a survey was made of Sabine Pass Bar under the direction of Major Howell, by Lieut. H. M. Adams, who reported 6 feet of water on it. In 1877 and 1878 another survey was made of the bar and extending through the pass, under Major Howell's direction, and the survey just completed under my direction shows that since 1873 no material changes have occurred except that where narrow channels were dredged through the bar, particularly on the crest and outer slope, they failed to maintain themselves.

A condensed history of the work for the improvement of Sabine Pass and its bar is about as follows: In 1853 Lieut. Henry L. Smith made an examination and partial survey, and estimated for a dredged channel cut to 9 feet depth at a cost of $7,000, and finally says that "nothing seems necessary to be done to improve the bar at the entrance of this harbor." See page 945, Chief Engineer's Report, volume 1, 1875. In 1873, Lieutenant Adams, in his report, says:

No improvement seems to be required on the Sabine (Pass) Bar. The vessels now in the Sabine trade have no trouble in crossing the bar at ordinary low water.

In 1875 Major Howell reported a plan and estimate for dredging a channel across the bar (page 946, volume 1, 1875, Chief of Engineers' Report; also page 902, report for 1879).

Congress appropriated $20,000 for this work. The work was let by contract. The contractors took out about 33,000 cubic yards of soft material by dredging, and then threw up their contract. In 1876 Congress appropriated $38,000 additional for the work, proposals were invited, but as the lowest bid would not complete a channel 12 feet deep over the bar all bids were rejected. The United States dredge-boat Essayons went there and about half completed a channel 12 to 15 feet deep, when her boilers failed. In January, 1878, the dredge-boat McAllister, with all on board, was lost in attempting to go to Sabine Pass from the Mississippi River. In 1878 the Essayons resumed work and obtained a channel 12 feet deep, 75 feet in its least width, and about, 18,000 feet in length. She was then taken away for repairs. In 1878 $30,000 was appropriated. In 1879 $25,000 was appropriated, and in 1880 $50,000 more was appropriated. In September, 1880, the Essayons again went to Sabine Pass, and remained until August, 1881, having worked on the bar 482 hours during this time, when she was again sent away for repairs. In June, 1881, Captain Davis, United States Engineers, who had recently been assigned to the work, said in his report:

I carefully sounded the bar from a small boat, running diagonally across the channel from side to side. On every crossing but three I found 12 feet or more, on the three crossings the soundings being 11.9, 11.9, and 11 feet respectively, which, considering

that up to that date no dredging had been done in over a month, was a better showing than I expected. Still the deep water was narrow and difficult to find. The Coast Survey steamer Gedney, light-house steamer Geranium, and revenue cutter McLane all report shoal water of late, about 54 feet, showing that the line of deep water must be very narrow and impracticable for purposes of navigation.

The survey just completed shows how little of the former dredged channel remains. It is so narrow and so nearly obliterated that in many places but one sounding could be obtained in crossing it.

The appropriations and allotments to the present time applicable to Sabine Pass have aggregated $320,000, of which about $167,000 has been expended, by far the greater portion in dredging and repairs to dredging machinery, and for which we have no practicable channel to show. There remains now available for use on this work in round numbers $153,000.

The bar at Sabine Pass is composed of a sticky, soft, blackish blue mul, known to be such by borings and probings made on January 2, 1882, to a depth of 30 feet below the water surface. The borings were made in various places on the bar, some on the crest, others on the inner and outer slopes. Gas pipes were pushed through the mud to depths of 30 feet and their contents examined. An iron rod, three-quarters of an inch square and 20 feet in length, pointed at its lower end, would of its own weight penetrate from 6 to 12 feet in the mud; two men, by pushing on it with a slight effort, could force it down its full length, and could push a 14-inch gas pipe down 30 feet. The bar is probably a drift and wave bar, and is certainly not a delta bar, for the reason that the Sabine and Neches rivers, which carry considerable solid matter, drop this matter at or near their mouths, near the head of Sabine Lake, whose waters form a settling basin for this sediment, which is dropped about 25 miles above the Sabine Pass Bar. It is thought that the mud of which this bar is composed is eroded from the soft alluvial soil forming the coast for several hundred miles to the eastward, and is brought here by the wind waves and tidal currents. When the Essayons was cutting at the channel in 1881 it was reported that there were some clay ridges running across the channel and underlying the mud at a depth of about 16 feet below the water surface. As I could find none of these clay ridges, and as no borings. had previously been made on or near the bar, inquiry developed the fact that the clay was supposed to be there on account of the difficulty which the Essayons had in cutting through it and by the color which the suspended particles gave the water while being stirred up.

In searching for this clay on January 2, 1882, with a pole, in a small boat, I found numerous places where the bottom was hard or offered a slight resistance to the pole, but upon pushing through it again found the characteristic soft mud at a depth of 2 to 3 inches below the slightly indurated mud. The surveying party who carefully examined the locality of the former dredged channel, found great numbers of these hard patches, but never anything approaching clay in appearance or hardness. The care with which this examination was made can be judged from the numerous soundings in and near the old channel lines. The only sand found in the vicinity of Sabine Pass is a small strip 10 to 15 feet wide, which of late years has formed on Texas Point.

We are therefore almost justified in stating that the bar is composed of soft mud to a depth of 30 feet below the water surface, as no traces of clay, sand, nor shell were found.

The tidal current flowing out of Sabine Pass, after leaving there, owing to the long distance of the bar from the throat of the pass, spreads and loses so much of its velocity, that it has not sufficient strength to

scour much, if any, of this mud from the bar. The feeble current, the softness of the mud, the narrow dredged channel, its steep side slopes, and the pounding of the sea on the bar, and the currents across the channel instead of through it, are amply sufficient to explain the nonmaintenance of the dredged channel.

An examination of the map shows the changes which have occurred in the shore lines of the outer portion of Sabine Pass within the last three years. Louisiana Point has in places washed away about 200 feet in distance, while Texas Point has made out about the same distance.

TIDES.

On the map is shown a diagram of the tides, reduced from the selfregistering gauge, for the month of December, 1881. We find the mean rise and fall of the tides to be 1.4 feet, while the extremes between the highest and lowest water during the month was 4.4 feet.

The height and time of duration of the tides at this locality are very much influenced by the winds. On two occasions in November and December, 1881, the tide was running flood for twenty consecutive hours, and in nine instances it ran ebb for sixteen consecutive hours.

By tabulating all of the tides during November and December, 1881, we find that the average duration of the flood tide was seven and threetenths hours, while that of the ebb was nine and three-tenths hours.

This unexplained, would indicate that the ebb was much more sluggish than the flood tides, when the contrary was known to be the fact from numerous current observations, and is due to the drainage water carried out on the ebb tide. Owing to the contrary currents in the pass flowing out on the surface for over two hours when a current at a lower level was running in it was almost impossible to gauge the volume of water passing through the pass in any tide with anything like accuracy. We found on the bar the mean rise and fall of the tides to be about 1.4 feet; at the town of Sabine Pass, the mean height of the tide was a little less, but over 1 foot in height. In the Sabine and Neches rivers, 50 miles from Sabine Pass, the tides are said to be felt, and yet at the mouth of both of these rivers, where the bars have been dredged, we have no records of the tidal range. For our purposes we can get a good idea of the volume of the tidal prism by considering Sabine Lake as our tidal reservoir.

The lake is about 15 miles long by 8 miles in width covering an area of about 120 square miles. At the lower end of the lake the tide rises 1 foot. At the northern end of the lake we dont know what the tide is, so we shall call it 0. This gives a mean height of one-half foot over an area of 120 square miles, or a volume of 1,672,704,000 cubic feet, which flows in in seven and three-tenths hours and out in nine and three-tenths hours. This gives a flow during flood tide of an average of 63,650 cubic feet per second, and during an ebb of 50,000 cubic feet per second.

The Neches and Sabine rivers drain an area of country embracing about 9,000 square miles, over which there is an average annual rainfall of upwards of 50 inches of rain. (The average for ten years at Galveston, only 60 miles distant, is 51.68 inches, and we know it to be more in the timbered country of these rivers.) Calling the rainfall 50 inches, and allowing one-half to be lost, we would then have 155,282 cubic feet of water per square mile per day which must flow out in 13 ebb-tides, or say fourteen hours, or at an average rate of 27,727 cubic feet per second. This added to the 50,000 cubic feet per second mentioned above, gives the ebb tide volume an average steady flow of 77,727 cubic feet per

second. This flows through Sabine Pass. At two places in the pass where it is narrow-one opposite the upper end of the town and the other opposite the light-house-the two places being about 4 miles apart, careful cross-sections were made, and in these sections numerous current observations were made. The area of the upper or hotel section was 28,112 square feet, while that of the lower or light-house section was 27,376 square feet. A mean of the two would be 27,744 square feet. If, now, we assume that the tidal flow was regular and uniform, the rate per second of the flood-tide through this mean area would be 2.3 feet, while that of the ebb-tide would be 2.83 feet. Our observations in the two sections show current velocities on the ebb tide varying from 0 to 44 feet per second, which was the maximum observed. Current observations made on the crest of the bar in 1878 give the strongest ebb surface current at 1.7 feet per second; at a depth of 2 feet the velocity fell to nine-tenths of 1 foot, and at 4 feet depth (the water being but 6 feet deep on bar) the velocity was only one-half foot per second.

Of the flood currents observed on the bar, the greatest observed velocity was 1.1 feet per second.

From nearly two mouths' observations it was found that the flood-tide in its first quarter, and sometimes extending nearly through the second quarter, came in on the Louisiana side, gradually widening until, when running at its strongest, it seemed to concentrate from the Gulf toward the throat of the pass; the current would frequently run out on the Texas side for two hours after the tide had commenced to run in on the Louisiana side. The ebb-tides acted almost exactly opposite. The first of the ebb-current was always on the Texas side, then this thread began to widen and extend toward the Louisiana shore, until finally the entire current over the bar was an ebb-current. We also observed that after southerly winds, when the water was banked up in the Sabine Lake and the Sabine and Neches rivers were high, there would be a surface current running out during an entire flood-tide, and that this water was fresh enough to drink.

Outside of Sabine Pass there is an undoubted littoral current whose general direction is from the east towards the west. This is variable, depending on the wind, and runs with a velocity of from 1 to 3 miles per hour. This current is appreciable for at least nine months in the year. During and after a strong southeaster this current pushes in toward the pass, mostly towards the Texas shore, but this is ordinarily of but two or three days' duration.

We now have the results of several surveys of Sabine Pass and its bar, know something of its tides and currents, have made sufficient borings to determine the character of the bar, and also know that there is a variable littoral current here, and have had the experience of at least two dredged channels across the bar. With this information, it is required to project a plan and make an estimate for the improvement of Sabine Pass and the bar at its mouth.

The dredged channels were not maintained; the conditions for selfmaintenance were unfavorable, and were mentioned on pages 4-5 of this report. Dragging the channel with a large harrow attached to a steamtug was tried, and the experiment showed that the channel could not be improved by this method. Would protecting works on either or both sides of the cut have maintained it? Possibly; but such works of themselves would have been of the nature of jetties, and they would probably have to extend the entire length of the cut. The problem to be solved at the time the cut was made was to get a channel through the bar. This was done in the quickest and cheapest manner, by dredg

ing. It was not known whether the channel would be maintained or not. Had there been many steam vessels using the channel, the continuous cutting of the bottom and stirring of the mud might have helped to longer maintain the channel, but there was no commerce there for vessels of this class, hence no vessels worth mentioning. The few vessels (steam) that went there were on government business, drew less than 8 feet of water, did not know where the narrow cut was, and would, in consequence, get ashore, and do more damage than benefit to the cut. The experience gained from dredging here was valuable. It proved that a channel could be dredged, that it was expensive work, and that such channel, if let alone, would fill up again.

With this experience before us, to resume dredging now without some means of protecting the work done or to be done would be worse than a most serious error.

In the pass itself, where the pass is narrow (1,800 to 1,900 feet in width), we have good channels self-maintaining; the bottom of the entire pass, excepting here and there where a few small oyster reefs are scattered about, is of precisely the same nature; that is, soft, blackish blue mud, as that found on the bar. In these narrow gorges of the pass we find channels 25 feet deep and over 500 feet wide. Where the pass is much wider, we have of course the same volume of water, but less depth and a wider channel. That this depth, its production, and maintenance, is due principally to the velocity of the tidal flow, there is no doubt, and therefore, if similar conditions can be reproduced on the Sabine Pass Bar, there is no good reason why similar results should not be obtained there.

We can only hope to produce similar conditions by means of jetties. If we can concentrate a sufficient quantity of water on a limited portion of the bar, we get over that portion of the bar an increased current. This, if it produces a scour, makes and maintains the channel. The pass itself is sufficiently wide and deep, with its funnel-shaped mouth, to offer but little obstruction to the free movement of the flood-tide; the banks of the pass are the jetties which concentrate and confine the water through them, and the Sabine Lake is the reservoir into which the waters flow. If jetties be built, they must therefore be constructed in such a way as to offer the least resistance to an inflow of the tides, and yet control the outflow and direct it in a certain fixed direction.

Their distance apart, direction, length, height, cross-section, composition, and, finally, their cost, are matters of the greatest importance. They should be far enough apart to secure them against serious subsidence that may occur from the excavation of a deep channel between them, and their direction should be such as to direct the current passing out between them with or across the littoral current, and certainly not against it. The nearer they be placed together with the same volume of water flowing between them, the deeper ought to be the channel which they should produce, and the consequent greater danger of their undercutting and final loss. In the pass, at its narrowest place (opposite hotel), the banks are 1,820 feet apart, and there we have depths of 39 feet. At the light-house the banks are 2,145 feet apart, and the greatest depth in this section is 27.7 feet, having a channel through it 500 feet in width, of 22 feet in depth. As the waters of the pass form an 18-foot deep channel, except over a few small oyster reefs mentioned, we ought to try to get 22 to 25 feet depth of channel over the bar. The mean of the areas of cross-sections at hotel and light-house is 27,744 square feet, the respective areas are 28,112 and 27,376 square feet, differfrom the mean only 1.3 per cent., while their mean depths are re

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