W. W. ASHE
U. S. FOREST SERVICE

Three rivers determined the location of Pittsburgh. They have been important factors in creating its industrial position; they are now important agents affecting the health and earnings of thousands of its citizens. The two score of iron and coal towns which are known as the Pittsburgh District, fringe the banks of these rivers. Mine, factory and furnace alternate with the residence settlements of the laborers, and they and the railroads compete with the streams themselves for ownership of the narrow strip of land between low water and flood crest. With every recession of the floods, man crowds the streams, only to be driven back when they reassert their suzerainty. Whatever can be done therefore, to tame their caprices, to equalize their flow, either by lowering the flood crests or increasing the low water stages, adds to the well-being and prosperity of men who work at forge and furnace, or go with the barges,—men whose living is from day to day, and to whom the idle day brings want.

The flood is the open expression of the rivers' authority. But they have another and more subtle influence. It is less direct, but it has a wider relation to the well being of the city, not only affecting the laborer who lives on the lowlands, but affecting all citizens alike. The rivers and their tributaries near which Pittsburgh and the surrounding towns are situated, furnish these in most instances with their water supply. The character of this water affects the health of the users, and their working efficiency.

All the drinking water used in the Pittsburgh District, except that from artesian wells or similar primarily pure sources, has been contaminated by the sewage of towns and villages higher up the rivers. Through such contaminated water typhoid fever and other zymotic intestinal diseases are widely disseminated. Scarcely a town in the steel and coal district has not been devastated by an outbreak of this dread scourge. The condition of Wilkinsburg is typical, its water supply being contaminated by the sewage of more than twenty towns. The new filtration plant for Greater Pittsburgh delivers to most of the city a drink much superior in quality to the highly polluted waters generally used. But filtration is only a first step toward purity, and toward decreasing typhoid fever and the other water-borne diseases. Filtration removes a high percentage of the pathogenic bacteria by which these diseases are transmitted; but a highly contaminated water, such as that of the Allegheny River, purified even by the best methods of sand filtration, is not pure water. Intelligent users must at length realize this and demand for their own health not a purified water merely, but a primarily pure supply, safeguarded by sedimentation and filtration against occasional contamination. Within easy reach of Pittsburgh and nearly every one of its satellite towns, lie abundant sources of primarily pure supply, in the forest-protected mountain streams.

Hitherto the cost of purchasing a forested watershed and holding it as unproductive property has deterred cities from seeking such sources. That difficulty no longer exists. Forest lands have now a recognized and constantly increasing earning power. If a watershed is purchased at a reasonable price and is well managed, it will become, as stumpage further appreciates in worth, a valuable municipal asset. Or if a town is small and unwilling to assume the responsibility of such management; it can well co-operate with the state in developing a system which will secure to it pure water, and at the same time preserve to the state the earning power of its forests which are among its most valuable natural resources.

Domestic water supply, however, is largely a matter local to each town or each group of towns. But the wage earners of the whole Pittsburgh section are yearly vitally affected by the rivers in a different way. The earnings and even the lives of thousands, especially of those living in the low districts of the larger cities, are threatened by the winter and spring floods. These floods frequently result in losses to wage earners aggregating several million dollars a year. In the flood of March, 1907, it is estimated that more than 2,000 families in the river districts of Pittsburgh, and an equal number in the low lying sections of nearby cities, were forced from their homes or their stores by high water. Quantities of personal effects were injured or destroyed; lives were lost; and much suffering followed the winter exposure. The effect of the flood in increasing certain kinds of disease is shown by a comparison of the pneumonia and typhoid records in the flooded wards of Pittsburgh. Dr. Beaty of the Pittsburgh Bureau of Health gives us the number of cases of these two diseases in certain wards on the North Side, which are largely tenanted by laborers, and were partly inundated.

In March and April, 1906, when there was no flood, there were fourteen cases of pneumonia and forty-eight of typhoid fever.

In March and April, 1907, when the flood had a height of thirty-six feet, there were forty cases of pneumonia and 118 cases of typhoid fever, more than twice the number of the preceding year.

During the flood the water and dwellings in these districts became badly contaminated by human waste, since the flooding of toilets and sewers prevented their use. At the same time many families usually dependent upon street hydrants for domestic water had to make use of this extremely impure river water. This affected large numbers of people, many of them recently arrived foreigners unacquainted with methods of securing ready relief. But a more general suffering was occasioned by the loss in wages through the closing of large establishments whose plants were flooded. It was estimated at the time by one of the local newspapers that more than 100,000 people in the Pittsburgh District were idle for an average period of a week on account of the March flood of 1907. A typical example is the National Tube Works, where different departments were closed from ten to fourteen days, throwing about 10,000 men out of regular work. About 4,000 of these were employed for three days as laborers, cleaning up after the water subsided. The same thing is yearly repeated in many other large factories as well as on the railroads. It is no exceptional occurrence. A similar, though less severe flood occurred two months earlier the same year and another in March, 1908. It is indeed an exceptional spring when there is not a flood. The losses to laborers by curtailment of wages from this cause are seldom so excessive as they were in the flood of March, 1907, but they amount annually to more than $100,000. Moreover, this loss takes place in the winter, when the wage earner can least afford it.

The river floods cannot be prevented by local effort. Their damage is by no means confined to Pittsburgh; it extends the entire course of the Ohio River and its most important tributaries; its causes originate in other states besides Pennsylvania. Although the state and even the cities might well co-operate in certain ways, the prevention of these floods is a problem for the Federal government to consider.

The cause of a flood lies partly in natural conditions. The run-off of the Allegheny and Monongahela Rivers is naturally concentrated and the highest floods occur when a deep snow on a frozen soil is suddenly melted by heavy warm rain. But their height has been accentuated by human agency; and this points to the two necessary phases of river flood control work. One is the re-establishment of normal forest conditions. This means not so much a great extension of the forest area, although there are many steep slopes now cleared which should be re-wooded; but it means the restocking as densely as possible of lands which have been cut or badly burned and are thinly or partially wooded. This is a means to an end. The forest produces a deep mat of leaves and mould, the humus which not only has a high water storage capacity itself but determines largely the porousness and absorptive power of the underlying soil. This function of the forest is not incompatible with the use of its timber. The most rapid growth of timber is secured by maintaining the deepest humus; but the cutting of it must be adjusted under skilled direction in order not to jeopardize the water storage function of the soil.

Furthermore, there is need of more evergreen forests. The pine and hemlock have been largely removed from the mountain sources of the Ohio. But these trees prolong the melting of deep snows, even under warm rains, for several days longer than deciduous trees. The re-establishment of forests of conifers will therefore contribute to lowering the crests of floods by distributing the flow over five or six days instead of two or three. This is one phase of the work of river control.

On account, however, of the large areas of open farm-land that lie on the watershed of the Ohio and that cannot be reforested, additional means are necessary for storing the surplus storm water. There should be storage reservoirs such as are now being used at the head of the Mississippi River for regulating the flow of the river above St. Paul. These reservoirs must be on wooded watersheds; otherwise they will silt up and they will hold back some of the storm water and lower the height of floods, they will have an additional value for they can be used as reservoirs for domestic water supply. They can also be made to increase the dry season flow of the streams, thus furnishing a stable water power for industrial use and permitting steady navigation during summer and autumn when the water stage is frequently too low even for coal barges. Thus, by means of the forests will be secured not only a reduction in floods but also a greater earning capacity to the region through the development of the latent power of its streams.

The rivers, then, are at once the making and the menace of Pittsburgh. It is through the forests and by reservoirs that the menace can be removed and the highest utility of the streams established. The purity of the water for drinking purposes can thus be assured. This involves a betterment in the health of the community and an increase in the efficiency of the laborer. The equalization of the river flow can also be thus attained. And this involves, first, the lessening of flood losses, and, second, the increasing of the power of the streams to meet the exacting requirements of water power development. The lowering of the floods secures also a further betterment in health by improving the sanitary condition of the districts subject to inundations, and a betterment of economic conditions, both by giving the laborer more steady work during flood and low flow periods, and by opening to him, through the creation of new industries, a wider field of employment.