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sissippi, which are but two or three shorter distance than the Mississip. feet above the common tide water pi itself, it would take of a large near its mouth, gradually ascend column of water if its channel was with the plain of which they con. not very much obstructed.* Near. stitute the highest ridges, to the ly opposite to Manchac, but lower 33d degree of north latitude, where down the river, is Bayou Plaque. they are elevated above the low mine, a cut off from the Mississip. water mark of the river thirty or pi to the Chafalaya; but as there forty feet. The banks are, howe. is a considerable declination, in ver, subject to be overflowed this part of the plain, of the alluvial throughout this distance, except lands, and being unobstructed in at those points protected by levees its passage, it is rapid, and takes or embankments; this arises from off a large body of water; where a law incident to running water it leaves the river, however, its bed courses of considerable length, is five feet above the level of the which is, that the floods in them low water mark. About 88 miles acquire their greatest elevation as above Manchac, and just below the you approach a point nearly equi. 31st degree of latitude, is the Chadistant from their mouths and falaya. This is one of the ancient sources. The depth of the Mis. channels of the Mississippi river, sissippi is from 120 to 200 feet, and being very deep, carries off at decreasing as you approach very all times great quantities of water; near the mouth, to a moderate and were its obstructions removed, depth. Exclusive of a number of it would probably carry off a much small bayous, there are three large larger quantity. As the distance natural canals or channels, by from the point where the Chafala. which the surplus waters of the ya leaves the Mississippi, along its Mississippi are taken off to the gulf. channel, to the gulf, is only 192 The first of these above New-Or. miles, and that which the Missis. leans, is Lafourche, which, leaving sippi traverses from the point of the river at Donaldsonville, reaches separation to the gulf is 318, it is the gulf in a tolerably direct course evident that a given column of of about ninety miles. The La. water may be passed off in much fourche is about 100 yards wide ; less time through the channel of its bed is nearly on a level with the the latter stream. From this topo. low water mark where it leaves the graphical description of that porriver; its banks are high, and pro. tion of the plain south of the 31st tected by slight levees; and in high degree of latitude, it is evident, floods it takes off a large column of that, independent of the general water. Above Lafourche the Ba. and gradual declination of this plain you Manchac, or Iberville, con descending with the Mississippi, necting with the lakes Maurepas it also has a more rapid declination and Ponchartrain, takes off into the towards the Lakes Maurepas and gulf, through the Rigoletts and Ponchartrain on the east, and to. other passes, a considerable por. tion of the surplus waters of the Mississippi ; the bed of this bayou * The difference between the highest is 14 feet above the level of the
elevation of the waters at the afflux of
tho Manchac, and the lowest level of the low water of the Mississippi, and tide in Ponchartrain, is from 27 to 80 as it reaches tide water in a much foet.
wards the valley of the great Lake plished by increasing the capacity of Attakapas on the west, and it and number of outlets of the na. may, as to its form and configura. tural channels by which the water tion, be compared to the convex is now disembogued, and by forming surface of a flattened scollop shell, other artificial ones, if necessary, having one of its sides very much by which the volume of water that curved, and the surface of the other enters into the lower plain of Loui. somewhat indented; there is, siana, in any given time, may be therefore, good reason to believe discharged into the gulf of Mexico that, by conforming to the unerring within the same time. If that volume indications of nature, and aiding were ascertained with any tolera. her in thcse operations which she ble degree of accuracy, then the has commenced, this plain may be number and capacity of the chan. reclaimed from inundation.
nels necessary for taking it off into The quantity of water which has the gulf might be calculated with been drawn off from the Missis. sufficient certainty. A reference sippi, through the Iberville, the to the map of that country will Bayou Lafourche and the Chafa. show that the rivers which dis. jaya, has so reduced the volume charge themselves into the lower of water which pagses off through plain of Louisiana, and whose the Mississippi proper, that indivi. waters are carried to the gulf in dual enterprise has been enabled common with those of the Missis. to throw up embankments along sippi, drain but a small tract of the whole course of that river, upland country; for Pearl river, from a point a little below that and, if necessary, at a very mo. where the Cafalaya leaves the derate expense, the Teche, may Mississippi nearly to its mouth, and be thrown into the ocean by sepa. for forty or fifty miles on each side rate and distinct channels. of the Lafourche; the lands thus At the thirty-first degree of north reclaimed will not, however, ave. latitude, and near to the point rage forty acres in depth, fit for where Red river flows into, and cultivation, and may be estimated the Chafalaya is discharged from, at 400,000 acres. This is certain the Mississippi, the waters of that ly the most productive body of land river are compressed into a nar. in the United States, and will be in rower space than at any other point a very short period, if it is not at below the 33d degree of north present, as productive as any other latitude; this may be considered known tract of country of equal as the apex of the lower plain. The extent.
contraction of the waters of the If the waters drawn off in any Mississippi at this point is occa. given time from the Mississippi sioned by the Avoyelles, which, through the natural channels, now during high water, is an island, and formed, were delivered into the is alluvial land, but of ancient ori. gulf through those channels in the gin; from this island a tongue of same given time, then they would land projects towards the Missis. not overflow their natural banks, sippi, which, though covered at and the adjacent lands would be high water, is of considerable reclaimed; but this is not the fact; elevation. It is probable, thereand the object can only be accom fore, that at the point thus designa. ted, a series of experiments and off a considerable portion of the admeasurements could be made, water by artificial channels. The by which the volume of water dis. Red river, arrested in iis direct charged in any given time, on the progress by the elevated lands of lower plain, by the Mississippi, at Avoyelles, is deflected in a direc. its different stages of elevation, tion contrary to the general course might be ascertained with sufficient of the Mississippi, and traverses accuracy to calculate the number the whole width of the upper plain and capacity of the channels ne. in a circuitous course of upwards cessary to discharge that volume of of thirty miles before it reaches water into the gulf of Mexico in that river. There is good reason the sanie time. With this data, to believe that the waters of the the practicability and the expense Red river, or a very large portion of enlarging the natural, and ex. of them, in times past, found their cavating a sufficient number of way through Bayou Bauf and the new, channels to affect this objcct, lake of the Attakapas to the ocean; might readily be ascertained. If and during high floods a small por. that work could be accomplished tion of the waters of that river are by the government, every ibing now discharged into the Bayou else in respect to the lower plain Bauf, at different points between should be left to individual exer- the Avoyelles and Rapide. A deep tion, and the lands would be re- cut from the Red river, through the claimed as the increase of popula. tongue of elevated alluvial land east tion and wealth of the country of the Avoyelles, to the Charalaya, might create a demand for them. and opening the natural channels
The contraction of the plain of by which it now occasionally flows the Mississippi by the elevated into the Bayou Beuf, would pro. lands of the Avoyelles, and the bably take off the waters which ac. manner in which Red river passes cumulate at the lower termination through the whole width of the of the upper plain with such rapi. upper plain, to a distance of nearly dity, and reduce their elevation so thirty miles, has a strong tendency much as to enable individual enterto back up all the waters of the prise and capital to continue the upper plain; therefore it is that, embankments, which now termiimmediately above this point, there nate below this point, not only is a greater extent of alluvial lands, along the whole course of the Mismore deeply covered with water sissippi, but along all those extenthan at any other point, perhaps, sive water courses running through on the whole surface of the plain the upper plain. of Louisiana; and at some distance The Tensa, a continuation of below this point, the embankments Black river, is, for tifty miles above of the Mississippi terminate. To its junction with Red river, a deep enable individuals to progress with water course, and in breadth but little these embankments, and to facili. inferior to the Mississippi. It draws tate the erection of others along but a very small portion of its wa. the water courses, and to reclaim ters from the high lands, but com. with facility the lands of the upper municates with the Mississippi by plain, it will probably be found to a number of lakes and bayous, ai be indispensably necessary to draw different points, from near its mouth to its source, which is near counter currents in every possible the 33d degree of latitude, and direction ; but when the foods through these channels aids in have aitained their greatest known drawing off the surplus water of height, then this whole plain be. the Mississippi, while it continues comes covered with water, from a to rise; when the Mississippi, how. few inches to twelve teet deep, as ever, retires within its banks, the its surface may be more or less de. waters in these bayous take a dif. pressed ; and if it could be exferent direction, and are returned posed to view, would exhibit the through the same channels into the appearance of an immense lake, Mississippi. Particular local causes with a few insulated spots dispersed will produce this effect at particu. throughout it, such as the island of lar points; but the general cause, Sicily, the banks of the lakes Con. so far as these bayous connect with cordia, Providence, and Wash. the Tensa, will be found in the fact ington, and some very narrow strips that th -re is not a sufficient vent partially distributed along the banks for the waters of the upper plain of the Mississippi and the other at the point of connexion with the water courses. If the whole of the lower plain of Louisiana. The upper plain were reclaimed in the Tensa is also connected, in times manner above mentioned, then the of high water, at several points, waters being contracted into mueh with the Washita and its branches. narrower channels would necessaWhen the Mississippi has risen to rily be very considerably elevated a point a few feet below its natu. above the point to which they now ral banks, the whole of the upper rise; and, passing off on the lower plain of Louisiana is divided by the plain with greater elevation and natural channels which connect the greater rapidity, and having only Mississippi with the Tensa, and the present natural channels of the Tensa with the Washita, into a outlet to the gulf, the inevitable number of distinct islands of va consequence would be, that the rious extent. The banks of the whole of the lower plain would be rivers and the natural channels inundated, and probably parts of which connect them are very ge. Attakapas and Opelousas would nerally the most elevated lands; again be subject to inundation. and each and all these islands The reclamation of both the might be reclaimed from inunda. plains of Louisiana will depend, tion by embankments, thrown en- under any possible plan that may tirely around them, of from six to be proposed, upon the practica. twelve feet high, provision being bility of tapping the Mississippi and made to take off the rain water, Red rivers, at one or more points, and that occasioned by leakage and to an extent that may draw off and accidental crevices in the rapidly such a quantity of water banks, with machinery. While the as will prevent the refluent waters Mississippi is rising, the waters are now collected just above the 31st carried off through these natural degree of latitude, from rising to channels and their outlets into the the heights to which they now do, lakes and the lowest and most de and the practicability of delivering pressed parts of the plain. During the waters into the ocean within pethis process, there are currents and riods equal to those in which they were drawn off. We have seen The course of the Mississippi that the natural channels of the from Donaldsonville to New-Or. Lafourche, Plaquemine, Iberville, leans being nearly parallel to the and the Chafalaya, have so reduced gull, and the distance to the gulf the mass of water in the Missis. across that part of the plain being sippi, below their points of afflux, much shorter than that by its natu. as to enable individuals, by very · ral channel to tide water, that pormoderate embankments, to confine tion of the river presents eligible that part of the Mississippi within points for tapping, particularly near its banks. The Lafourche is the to New Orleans; the commerce of only one of these natural channels which, in time not perhaps distant, that takes off the waters to the may require a deep cut to be made ocean so rapidly and directly as to to the gulf. The width of the river enable individuals to erect levees at Donaldsonville being about or embankments along its whole seven bundred yards, the rise above course. The passes of the Rigo- its natural banks about one yard, lets, and at Berwick's bay, not and its velocity two and a half being sufficient to take off the wa. miles an hour; if, then, by one or ters which 'flow through them as more tappings below this point, a fast as they are discharged into volume of water of the above dimen. their resevoirs, it is evident that no sions could be carried off to the beneficial effect could be derived ocean will equal velocity, then from tapping the Mississippi at any would the 'highest elevation of the point on its eastern bank, or at any river be reduced very considerably point on the Western bank above every where below such tapping, the Lafourche, unless the capacity and for some distance above. Such of the outlets at Berwick's bay and a reduction of the elevation of this the Rigolets be greatly enlarged. part of the river, aided by the clear. The passes at the Rigolets are well ing out of the rafts from the Chafa. known; and it is probable that by laya, would possibly produce so enlarging them, and cutting off that great a reduction of the refluent portion of the waters of Pearl river waters at the junction of the Red which now flows through them, and Mississippi rivers, as to enable they might be made adequate to individuals to proceed gradually to take off, in a sufficiently short pe. the reclamation of the whole of the riod, the waters of Iberville and upper plain by common embank. those of the short rivers of Beli. ments. It would then require only ciana, so as to prevent that portion an increased capacity to be given of the plain between the Iberville to the outlets of the lake of Attaka. and the city of New Orleans from pas, to insure the reclamation of being inundated, except so far as both plains. But if this effect can. the waters of Ponchartrain, ele. not be produced by the tappings vated by high winds and tides, may below the Lafourche, then they produce that effect. It is only, must be made at points higher up, therefore, on the west bank of that either between Plaquemine and river, or the south bank of Red the Chafalaya, or at a point about river, that the proposed tappings the mouth of the Bayou Lamourie, can be made with the prospect of or Du Lac, on Red river. A refea successful issue.