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System of New Orleans

A Notable Engineering Work that is Transforming the Entire Aspect of this Southern Metropolis

By DAY ALLEN WILLEY

T

HE CITY of New Orleans has begun a new era in its history, thanks to a public improvement which is one of the most notable of American engineering feats. As a result of this great work, the community at last stands on "dry land" for the first time since it was founded by the French pioneers. For nearly two centuries, the inhabitants of New Orleans have been living on the surface of a great natural sponge. Owing to the topography of the city, there is no natural drainage whatever, and the formation is such that holes dug to a depth of even two or three feet would reach the water that saturated the ground nearly to the surface. Some scientists have believed that the site of the city is a part of the "trembling prairie" which is so extensive in this portion of Louisiana.

Foundations of Mud and Water

As a result of this condition of affairs. the construction of buildings even three stories in height has been a difficult problem, as it was found to be practically impossible to secure a stable foundation for them. In consequence, the great majority of the dwellings have been erected of wood; and the comparatively few structures of brick and stone have been built with great care, to prevent their foundations from settling to such an extent as to injure or destroy the buildings. The history of the Spanish fort at Belize, which was erected near the mouth of the Mississippi river and sank almost completely out of sight, is well known. The walls of the venerable St. Louis Cathedral settled after completion so that its towers crumbled. Among the engineers who realized the problem to be solved. in the construction of buildings in New Orleans, was General Beauregard, the architect for the New Orleans Custom

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problems which presented itself was how to get rid of the drainage, for, after an examination of the area to be drained, it was found that all of the water must be forced to a higher level than the site on which the city stands. As is well known, nearly all of the land on which

FIG. 2. NASHVILLE AVENUE LINED AND COVERED CANAL, NEW ORLEANS, IN COURSE OF CONSTRUCTION.

the city has been built lies below the surface of the Mississippi river to such an extent that, were it not for the levee protection, the water would rise to the second story of the buildings in the lower portion of the city. To furnish an adequate drainage system, it was necessary to construct a series of canals which would serve nearly 200 square miles, and to connect them with a series of pumping stations of sufficient capacity to force the water into a tributary of the Mississippi, elevating the water to heights varying from 6 to 18 feet according to the levels of the canals. It was calculated that the quantity of rainfall and other surface water to be removed, was so great that it would be necessary to carry it away at a rate of nearly 60,000 gallons each second. In fact, the project has been considered by experts to be one of the most difficult ever attempted by engi

neers.

The City of Mexico was converted from a plague spot of disease into a healthy city by constructing a tunnel through the mountain side surrounding it. This has been a notable achievement, but the force of gravity has assisted in

moving the sewage. At New Orleans mechanical power entirely is employed.

Canals for Drainage and Sewage The improvement in New Orleans, which was commenced in 1897 under the supervision of Mr. George G. Earl, with Mr. W. C. Kirkland engineer in charge, has progressed so rapidly that a very large section of the city is at last completely served by the drainage canals and pumping stations. In all, about thirty miles of trunk or main canals have thus far been completed, including channels extending beneath the principal thoroughfares, but excluding branches which reach the smaller streets. This network of waterways is so arranged that the adjacent buildings can be connected with them by pipes, affording sanitary facilities of which in the past the city has been almost entirely destitute. The canals

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System of New Orleans

A Notable Engineering Work that is Transforming the Entire Aspect this Southern Metropolis

By DAY ALLEN WILLEY

T

HE CITY of New Orleans has begun a new era in its history, thanks to a public improvement which is one of the most notable of American engineering feats. As a result of this great work, the community at last stands on "dry land" for the first time since it was founded by the French pioneers. For nearly two centuries, the inhabitants of New Orleans have been living on the surface of a great natural sponge. Owing to the topography of the city, there is no natural drainage whatever, and the formation is such that holes dug to a depth of even two or three feet would reach the water that saturated the ground nearly to the surface. Some scientists have believed that the site of the city is a part of the "trembling prairie" which is so extensive in this portion of Louisiana.

Foundations of Mud and Water

As a result of this condition of affairs, the construction of buildings even three stories in height has been a difficult problem, as it was found to be practically impossible to secure a stable foundation for them. In consequence, the great majority of the dwellings have been erected of wood; and the comparatively few structures of brick and stone have been built with great care, to prevent their foundations from settling to such an extent as to injure or destroy the buildings. The history of the Spanish fort at Belize, which was erected near the mouth of the Mississippi river and sank almost completely out of sight, is well known. The walls of the venerable St. Louis Cathedral settled after completion so that its towers crumbled. Among the engineers who realized the problem to be solved in the construction of buildings in New Orleans, was General Beauregard, the architect for the New Orleans Custom

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of the best in the world, and, in some respects, resembles that of Paris. Figs. 2 and 3 show typical scenes during the construction of these canals.

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brick arches to uphold the roadway. Considering the difficult character of the work, the system is considered to be one

Pumping to Higher Levels

The waterways are divided into eight groups, each being served by a set of pumps operated by electric power. In all, 26 pumps are in service, having a total discharging capacity of 7,600 cubic feet per second, with an average lift of 12 feet. They are connected by a system of wires with the generating station from which all of the power is secured. This building (Fig. 4) is 181 feet in length, 140 feet in width, and two stories high. An interior view is shown in Fig. 5. The building contains an equipment of 7 units, each consisting

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FIG. 5. INTERIOR OF CENTRAL POWER STATION, NEW ORLEANS DRAINAGE SYSTEM. One-half of engine room is here shown.

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