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147

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No. 147.

SURVEY OF SABINE PASS, TEXAS.

LETTER

FROM

THE SECRETARY OF WAR,

TRANSMITTING

A report of the Chief of Engineers of the results of the survey of the en

trance to Sabine Pass, Texas.

MARCH 29, 1882.-Referred to the Committee on Commerce and ordered to be printed.

WAR DEPARTMENT,

Washington City, March 28, 1882. The Secretary of War has the honor to transmit to the House of Representatives, for the information of the Committee on Commerce, a communication from the Chief of Engineers of yesterday's date, covering copy of a report from Capt. W. H. Heuer, Corps of Engineers, of the results of a survey of the entrance to Sabine Pass, Texas, made with a view of a reconsideration of the plan of improvement, and also copy of a report of the Board of Engineers for Fortifications, and for River and Harbor Improvements on the subject.

ROBERT T. LINCOLN,

Secretary of War. The SPEAKER

of the House of Representatives.

OFFICE OF THE CHIEF OF ENGINEERS,

UNITED STATES ARMY,

Washington, D. C., March 27, 1882. Sir: I have the honor to submit herewith a copy of a report to this office from Capt. W. H. Heuer, Corps of Engineers, of the results of a survey of the entrance to Sabine Pass, Texas, made with the view of a reconsideration of the plan of improvement, together with a copy of a report from the Board of Engineers for Fortifications and for River and Harbor Improvements, to which Captain Heuer's report was referred for examination.

For the purpose of securing deeper water over the bar at this place it was determined in 1877 to confine the improvement to dredging a channel of a width only sufficient for the needs of commerce and 12 feet deep. This, however, has proved very expensive, owing to the locality

being exposed and distant from supplies, and insufficient because the material forming the bottom of the channel is such as to require constant dredging to prevent filling up and has led to the consideration of measures for the preservation of a channel, among others, by jetties with the view of contracting the width of the entrance so as to induce scour. In the reports herewith submitted the subject is treated so fully that I beg leave to suggest they be transmitted to the House of Representatives for the information of the Committee on Commerce. Very respectfully, your obedient servant,

H. G. WRIGHT, Chief of Engineers, Brig. and But. Maj. Gen. Hon. ROBERT T. LINCOLN,

Secretary of War.

IMPROVEMENT OF SABINE PASS, TEXAS.

OFFICE UNITED STATES ENGINEERS,

New Orleans, La., January 28, 1882. GENERAL: I have the honor to forward in a separate package by mail this day a report, project, and estimate on Sabine Pass, Texas. The maps will be forwarded by express on the 30th January, 1882.

As the estimated cost of the work exceeds $3,000,000, I have to request that the report be referred to a Board of Engineers for consideration, report, and advice. Very respectfully, your obedient servant,

W. H. HEUER,

Captain Engineers. The CHIEF OF ENGINEERS, U. S. A.

REPORT.

UNITED STATES ENGINEER OFFICE,

Nero Orleans, La., January 28, 1882. What is known as Sabine Pass is a body of water a little more than 7 miles in length, varying in width from one-third to 14 miles, and, with the exception of about 900 feet in length in the aggregate, has a channel through it carrying a least depth of 18 feet of water, whose average width is about 500 feet. This channel in places has depths as great as 39 feet. The 900 feet exceptional length above referred to contains depths varying from 12 to 17 feet, lies on a shell reef which can be easily and economically dredged through.

The pass forms a portion of the boundary between the States of Louisiana and Texas, and connects the waters of the Gulf of Mexico with those of Sabine Lake, into which the Neches and Sabine rivers, each having numerous small tributaries, flow.

As we approach the southern or Gulf end of the pass, we find the banks much further apart than they are higher up, thus forming a funnel or bell shaped mouth, beyond which there is a large soft mud bar having a tolerably uniform depth of a little less than 7 feet of water on its crest, and of which the shortest distance across measured between the 18-foot curves in 18,470 feet, or about 31 miles. The inner slope of

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 61 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 abont 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

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that up to that date po 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 mu:l, 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 evd, 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 hard

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

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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 suflicient to explain the nonmaintenance of the dredged channel.

An examination of the map shows the cha es 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 consecntive 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 rainfali 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 14 ebb-tides, or say fourteen bours, 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

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