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land, the other two by prairie coulées. These shoals cause much delay to steamers, as they can cross only at high tide; their removal by dredging and closure of the channels causing them will help navigation. From the ninth to the twentieth mile the last depth is 4 feet at low-water, which is sufficient for the boats in the trade. There are a few snags and some overhanging trees. Below the twentieth mile the river gradually increases in width and depth to its month; the only obstructions are a few snags. Abbeville is on the twenty-fourth mile, and is the largest town on the river, and the shipping point for the region to westward. The river enters Vermillion Bay in a little cove at its western end, which is a good harbor at its mouth; but there is a shoal bar between this cove and the bay, over which the depth at low tide is but feet. The channel could probably be improved by making a jetty of brush or cane fascines from the shore to the island, shutting off the incoming current over the mud Eat at rising tide, and forcing it to follow the course taken by ebb tide, which is the channel followed by boats. A chart of the river is made on a scale of

The estimated cost of improvements below Pin Hook bridge is as follows:
Clearing and removal of snags 5 miles from bridge, at $200.
Clearing and removal of snags next 15 miles, at $100.

22.000 yards dredging at mouth, at 25 cents.

Jetty

Engineering and contingencies, 10 per cent.

Total.....

$1,000

1,500

5,500

1,000

900

9,900

The commerce to be benefited is that of Vermillionville and Abbeville, with the

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EXAMINATION OF BAYOU COURTABLEAU, LOUISIANA.

UNITED STATES ENGINEER OFFICE,

New Orleans, February 27, 1880.

GENERAL: I have the honor to submit herewith report of Assistant Engineer H. C. Collins on examination of Bayou Courtableau, Louisiana, provided for in act of Congress approved March 3, 1879. Tracings of chart drawn to a scale of will be forwarded in a separate package. The recommendations of Mr. Collins as to plan of improvement are set forth in his report, and are concurred in. His estimates are also approved; $6,000 could be expended to advantage on the work during the ensuing fiscal year.

The work will constitute a permanent improvement in the ordinary acceptance of the word permanent.

The importance of the work and all information obtainable concerning the commercial statistics are given in the report of Mr. Collins.

The work is located in the collection-district of New Orleans.

The nearest light-house is at the entrance to Atchafalaya Bay.

Very respectfully, your obedient servant,

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C. W. HOWELL,

Major of Engineers.

REPORT OF MR. H. C. COLLINS, ASSISTANT ENGINEER.

NEW ORLEANS, LA., January 31, 1880.

MAJOR: I have the honor to submit the following report of the examination and sarveys of Bayous Boeuf and Courtableau, from the head of the Lamourie to the nction with the Atchafalaya River.

The bayou, though having two names in different parts of its course, and has been so considered in making this examination, is really one stream. Its former source was the Red River, and it empties into the Atchafalaya River.

Bayou Robert, which once brought the water from Red River and furnished a large portion of the water of this bayou, was closed many years ago, and with it all upper connection with Red River ceased. The water at low stage, which now forms the stream at the beginning of this survey, comes from the pine woods hills on the south side of Red River and to the westward of the bayou. Above the beginning of the survey is a large cypress swamp, which forms a reservoir and prevents any sudden floods from rains in the hill country.

At the low-water stage of the bayou about two-thirds the water coming from above is lost down the Lamourie.

A very small portion of the water now running down the Lamourie would suffice for all necessities of the few plantations on its banks; and closure of the bayou at its head, excepting what water was needed for them, would give fully double the present amount in Bayou Boeuf.

The banks and country on each side of the Boeuf are of red soil, which is evidently the deposit of Red River. The banks are nowhere caving, and are several feet higher than the highest floods.

The descent is from the immediate banks, away from the bayou on each side, to low cypress swamps.

The slope varies greatly, as the banks of the bayou are very uniform in their height, as are the cypress swamps, and the distance from the bank to the swamp varies between one-quarter of a mile and 3 or 4 miles. No levels were run across the valley to determine the differences of level between the top of the bank and the cypress swamp back of the fields, but it is probably 12 or 15 feet.

The bayou runs in great, sweeping bends, such as would be formed by a stream larger than it now is, and it had at some time sufficient water supply to overflow its banks at high river, and sufficient current to wear away its banks, as the bends are such as are made by caving banks.

Since the present conditions have been in operation the banks have become covered with trees and bushes from their tops to about the low-water line, and in many places cypress trees of great size have grown in the bed of the stream or on its immediate banks, and where they have been cut their stumps remain as low-water obstructions. The banks are everywhere cultivated, from the top of the ridge near the bayou back near to the cypress swamps.

Drainage is back to the swamps except in those bends where cut-offs had almost taken place at the close of the period of caving banks.

The lands are very fertile, and immense crops of cane, cotton, and corn are raised. The bayou, at the low-water stage, is very much too small, for 90 miles above Washington for navigation, even with the smallest boats, as it is but 1 foot in depth in many places, and any deepening of these places would but draw off the water of the pool above, and perhaps transfer the position of the shoal, but not in the least increase the depth for purposes of navigation.

Closure of Bayou Lamourie would furnish water enough to make a low-water channel of 24 feet, except at periods of long droughts, and were the logs in the bed removed and the overhanging trees cut, would probably afford a depth of 4 feet or more for the winter months, when there is most rain.

The small barges which are at present used can take freight on this depth, and the steamers can tow them; but for any really useful low-water transportation, locks and slackwater navigation will be needed. The survey of the upper portions of the bayou to within a few miles of Washington was made by Mr. George O. Elms, and that below was made by myself, with his assistance.

The cross-section made above the head of Lamourie gives a low-water area of 540 square feet in the pool where the cross-section was made.

At the extreme high-water of 1874, 3,040 square feet area and the tops of the banks 8 feet higher would increase this cross-section area, if they were full, 2,720 square feet, showing that the channel is capable of carrying double the water found in it at the highest floods.

The cross-section of the Lamourie, nearly 2 miles below its head, gave an area in the pool at low-water of 100 square feet, and at the height of high-water of 1874 of 620 square feet. The tops of the banks were 3 feet above this height.

The depth on the first ripple below the Lamourie, on the Boeuf, was but 1 foot, and its extreme width but 40 feet, giving a cross-section area at extreme low-water of but 28 feet.

The entrance of Bayou Clear, at the middle of the fourth mile, rather more than doubles the amount in the Boenf. It comes from the hills west of the delta valley. On the twelfth mile is a small bayou which enters from the west. Below this all the west side drainage goes to the Cocodrie Swamps, which here form the west side

of the valley and border on the west hills. That on the east side finds its way through swamp channels to Bayou Huffpower and Bayou Rouge.

No stream enters and none leaves until we reach the Huffpower on the forty-third mile, which is an old channel leading to the eastward, and much more filled by late deposits than the Boeuf, and is dry at its head with a rise of less than 7 feet in the Boeuf. It therefore does not in the least injure navigation in the Boeuf, as when there is a 10-foot rise but a very small stream runs down the Huffpower, and there is no risk of its again cutting out to take any large amount of water from the Boeuf, as it is decreasing and has little fall.

The banks are almost perfectly uniform from here to the mouth of the Cocodrie, which enters from the west at the end of the eighty-sixth mile, and below the mouth of which the name is changed to Courtableau.

The cross-section is almost exactly the same as at the head of the survey. The banks are of equal height above the high-water marks, being everywhere covered with overhanging trees.

The bed of the bayou has many logs and stumps and some standing cypress and gum trees. There are frequent bridges, all of which have draws for passage of steamers. The depth on the ripples is but 1 foot at extreme low-water, and in its narrowest place the width is but about 20 feet.

The overhanging trees are so thick that a rise which would give good navigation were they removed will only permit small steamers with a width of about 20 feet to pass, and they have smoke-stacks with joints to lower for passing under low trees.

Some years ago a lock was begun by a stock company, under an appropriation from the State. It was located at the upper end of a shoal 600 feet long, which is found just above the junction of the Boeuf and Cocodrie. It would not have been of any use if it had been completed, which it never was, as when there was water enough to get to it there was enough to do without it. It now forms a slight obstruction where one corner projects into the channel, but it can be easily removed.

The amount of water coming down the Cocodrie at low-water is more than double that which comes in from the Boeuf. The west bank of the Courtableau here at its head is also the west side of the delta valley, and high bluffs form the west bank of the bayou, rising 100 feet or more within half a mile.

One mile below the junction a cross-section was taken, at a place where there was a current of about 1 foot per second at the time, which was extreme low-water. The low-water area was 180 square feet, and that at the height of the 1874 water-mark was 3,400 square feet; this was several feet below the top of the bank and is the highest water-mark observed.

Although the alluvial bank on the east side, and all that above, is nowhere caving, the bank does cave all along the bluff land at every place where the stream touches it. The town of Washington has half a mile front on the bayou on the fourth mile, and the 3 miles above it are lined with overhanging trees on both sides, and there are many logs in the channel as on the Boeuf above.

Washington is situated on the west bank on a bluff formation, and it is a place of much importance as a shipping point for a large amount of freight, and head of navigation for the larger boats during a great portion of the year.

There is a draw-bridge about the center of the town, and a cross-section taken from it gave a low-water area of 140 square feet, and at the height of 1874 high-water mark it was 3,590 square feet; the rise at that time was 23 feet above extreme lowwater, yet was several feet below the top of the east alluvial bank.

There are very few overhanging trees below Washington, but near the middle of the fifth mile is a saw-mill, where for nearly half a mile the old saw-logs and butts of logs which have been cut off and rolled in form a complete blockade, with less than a 3-foot rise. All of them must be taken out.

The shoalest places have about 2 feet of water at extreme low. On the sixth mile Bayou Caron joins the Courtableau from the west, and with less than a 12-foot rise of the Courtableau it runs into it, but there is a connection 2 miles above, through the Maricoquant, which, with a rise greater than that in the Courtableau, takes the water to the southward, to the Teche. The Caron to this junction, the Maricoquant, and the Teche below, all have the same banks of Red River formation as the Courtableau, but the Caron above this junction is merely a hill stream, with black or gray deposit from the bluffs.

At Barry's Landing, on the thirteenth mile, the Teche leaves to the southward, and at times of great floods carries off a large amount of water from the Courtableau, but it is for the first 4 miles much obstructed and only runs at present with an 8-foot rise of the Courtableau.

It here bears marks of having once been far larger than it is at present. About the middle of the seventh mile Bayou Toulouse once ran out of the Courtableau and emptied into the Teche, but a dam has been made across its head and a ditch cut from it across the bottom land, entering the Courtableau near the beginning of the tenth mile, and causing a bad bar.

At the beginning of the eighth mile the Little and Big Ouacksha bayous enter, near each other, from the north, and at high-water times bring in some water from Red River.

Small steamers always run up the Courtableau at low-water as far as the landing below the Quacksha, and the depth between there and Barry's Landing is 6 to 10 feet, except where two drains enter, one from Bayou Toulouse and the other from the opposite side on the ninth mile. On each of these short bars is a depth of 3 feet at extreme low-water; both are of recent origin and can be removed by dredging or by removing their cause by closure of the ditches.

At Barry's Landing is a bar quite variable in its position, but which is caused by the high water from Red River backing up the Courtablean and that entering from the north side bayous running across the Courtableau down the Teche. The bar is near the head of the Teche, and at times of discharge down it in floods there is little or almost no down current in the Courtableau past that point.

The surface of this bar is washed off as the bayou falls, and there is but seldom so little as 4 feet depth on it at lowest water.

At the time of the survey, the middle of October, 1879-at extreme low-water as it then was-there was a slight current, amounting to 1 foot per second, on the shoal places as far down as the eighth mile, but below that the current slackened until at Barry's Landing and below it was about 1 foot in 10 seconds, decreasing below as the cross-section at low-water increases until it is so slight that small objects on the surface float up or down as driven by the slightest breeze.

In a bend on the eighteenth mile the bank is so washed that a fresh surface is exposed on a slide, and for 8 feet above low-water the bank is of blue clay, which does not wash, overlaid by 10 to 15 feet of Red River formation. The old red deposit once put on this blue clay slope appeared to have recently slid or been washed in. Near the top of the blue clay were some roots of cypress, which did not reach up into the red land above, and in the red land above were a few pieces of ancient drift found, and more or less of them everywhere on the Boeuf. Every one of these which retained the substance of the wood enough to enable me to determine what it was I found to be red cedar, and in many cases a log or piece of drift, though blackened and soft for an inch in depth, had yet inside that a sound red cedar heart, retaining not only the color but the smell of the new wood.

The outer side of the bend next below this had the blue clay bank exposed by washing off of the red surface, and it was the same height above water. At Barry's Landing the high-water of 1874 is near 2 feet below the top of the bank on the south side, but 2 miles below it is at the surface, and on the seventeenth mile is 3 feet above on the narrow ridge on the south side, and so high as to wash away fences a few hundred feet south from the bank. Nearly the entire distance from here to the Atchafalaya was then covered.

The land on the north side of the Courtableau is somewhat lower than it is on the south. Below where the banks of the Courtableau were covered deeply in the flood of 1874 the general course of that flood was southward directly, following the channel of the Courtableau for short distances only as it ran in the direction in which it was moving, and often for short distances running up the stream.

Near the end of the nineteenth mile is a pile of oak logs, reaching entirely across the channel, and the part of it which had not been removed is about 6 feet above lowwater. A channel through this barricade has been made by pulling out logs so as to give a low-water depth of 5 feet for a width of 50 feet.

Through changing their places in times of high-water these logs at times form an obstruction to navigation which may in some case be quite serious; but the whole block of logs can be easily pulled out on the bank at low-water and burned.

At the bend on the south side, near the end of the nineteenth mile, the blue clay surface is 5 feet above water, and in the opposite bend, 500 feet above, it is at the same height, covered in both cases by about 10 feet of red soil. The surface of the blue clay, in both instances, was evidently a cypress swamp when the red deposit began to be made, and the channel in the blue clay was made before that time and was much longer than the present channel, as but one side of the present channel is worn into the blue clay, while the opposite is Red River deposit, like that above the blue clay, filling an unknown proportion of the ancient bed.

The red soil, though resisting the washing of a current far better than that of the west bluffs of the valley at Washington, is easily washed compared with the blue clay.

On the twentieth mile Big and Little Darbon bayous enter from the north. Both have large channels, though bringing at low stages very little water. The Courtableau

is here, at low-water, 100 to 150 feet in width, and 13 to 15 feet deep.

At the middle of the twenty-first mile is a south-side bayou, which runs with an 8foot rise, and near the end of the same mile Bayou Jummel leaves on the south. A small sand-bar in its head is 3 feet above extreme low-water, but the channel is wide, and at high-water has a large discharge.

The bottom lands, on each side, are 13 feet above extreme low-water, and a watermark on trees was 54 feet higher. The high-water mark appears to vary greatly, depending on the escape to southward of the water coming in from the north, and near the Jummel it was 14 feet lower than a mile above.

Blue elay shows at every bend where the current meets any old bank.

Near the beginning of the twenty-third mile the bank on the north side is 12 feet high, but it falls before reaching the middle of the mile to 7 or 8 feet, and continues at that height, with some yet lower places, until the middle of the twenty-sixth mile, showing a strong current at high-river.

On the opposite south bank the high land has a break 1,200 feet wide, where the water runs with a 7-foot rise; it is much washed.

On the twenty-fourth mile two bayous leave on the south side, which run with a 5 to % foot rise, but the intervening land is 12 to 13 feet high.

The twenty-fifth mile has one bayou 60 feet wide and 5 feet deep at low-water at its head, but which is so choked below that no water escapes at extreme low-water. Three other bayous, which run with 5, 6, and 7 foot rise, leave on the right bank on the same mile, but the land between is 15 feet high; 74 feet of this is blue clay.

There are eight bayous on the south side on the twenty-sixth mile, the upper two of which run with a 2-foot rise; the next two with a 6-foot rise; next is Mamselle Bayou, which is 70 feet wide at low-water, but has no current at such time, though it is a very large stream at high-water; the other three are small bayous. Land between these is 10 to 14 feet higli, and shows a strong current at high-water, though the surface is little washed, being thickly covered with trees and bushes.

On the left bank, at the head of the twenty-seventh mile, is a high tract where blue clay shows 5 feet high, with 5 to 8 feet of red soil above it.

On the south side, a few hundred feet back from the bayou, at the head of the twenty-seventh mile, are two mounds 10 feet above the highest floods. Just below them the Fordoche Bayou runs out to the southward; its channel was 3 feet deep, but it had, at low-water, no current. This was the channel for steamers previous to clearing out the raft from the Atchafalaya, and it forms a connection through Bayon La Rose with Grand Lake below, and there are many cross-channels between it and the Atchafalaya. It has not been used since the opening of the other bayous. On its south bank I found an old high-water mark, made by drift, which was 9 feet above the surface where the bank was 13 feet high, showing that within 20 or 30 years a flood had risen here 22 feet above low-water. Blue clay on its bank is 7 feet and red soil 6 feet deep.

At the head of the twenty-eighth mile the right bank was 13 feet high, and this year's high-water mark 2 feet above it. Two narrow bayous run out with a 4 foot rise, and on the middle of the mile is a washed channel 1,000 feet wide, 3 to 6 feet above low-water. Much drift has lodged in it, which probably came from Bayou Bigereau, which by four mouths enters from the north. It is evidently a very large bayou at high-water, but no water enters from it at low-water. The entire distance, 2,500 feet, between its extreme mouths is a swamp but 3 feet above low-water and bearing marks of strong currents at flood seasons.

On the south side, at the beginning of the twenty-ninth mile, is a bayou which is entirely covered with standing trees, and its bed is but 3 feet above low-water. For one-half a mile below the blue clay is seen in the right bank 5 feet above water, with 2 to 5 feet of red soil above it.

One small bayou leaves at the end of this mile and one at the beginning of the next, and one enters from the north just opposite this last. Six hundred feet below, English Bayou leaves to the southward; it is 70 feet wide and 5 feet deep at low-water, but with no low-water current. In its banks, and those of the river near, the blue clay was 5 feet above water, with 64 to 8 feet of red soil above it.

Little Fordoche Bayon leaves at the end of the thirtieth mile, and a bayou enters from the north, directly opposite its head.

The depth of the Courtableau is here 18 feet, but it shoals very fast, and at the beginning of the thirty-first mile it is but 10 feet, 400 feet below but 63 feet, and 2,000 feet below the beginning of the thirty-first mile it has shoaled to but 1 foot. This shoal is called Little Devil Bar. It is of a loose, easily washed sand, and extends to 1,200 feet below the end of the thirty-first mile, being about 6,500 feet long at present.

Near the head of the bar a bayou enters from the north, and there is a mile of low swamp which is but 3 or 4 feet above low-water and is said to be all bayou at highwater.

The south bank is high except at the bayous, which run with a rise of 3 to 4 feet. The entire surface on the south bank is 7 to 14 feet above low-water. Floods from above on the Courtableau and from below on the Atchafalaya meet here and pass off to the southward through these bayous and over the bank. It is only at times of lowwater in the Atchafalaya and high-water in the Courtableau that any water runs from the Courtableau into the Atchafalaya, except at extreme low-water. There is a

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