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ADVICE TO CITIES AND TOWNS.
The following pages up to the 58th were contained in a report made to the Legislature Jan. 9, 1892, under the provisions of chapter 375 of the Acts of 1888. The portions of this report here given are the general report of the Board made under the provisions of this act, and the substance of replies made by the Board to such cities, towns, corporations and individuals as have applied for its advice relative to systems of water supply, drainage and sewerage under the requirements of the act. The portion omitted relates mainly to the work done at the Lawrence Experiment Station, a more complete account of which will be found in a subsequent portion of this volume.
During each of the years before the past one, since the Board was given the general oversight and care of all inland waters, and for the first three months of the past year, the rainfall in the State has been unusually large. This continued condition of abundant water supply and high flow in the streams has rendered scarcely noticeable the effect of the rapid growth in population during these years in exhausting the capacity of the present sources of water supply and in increasing the pollution of streams, but during the past summer and autumn a drought prevailed, which, although not as extreme as in some previous years, has indicated to many places that an additional supply of water was needed; and, as a consequence, a large number of applications have been made to the Board for its advice as to additional sources of water supply. More complaints of troubles from bad tastes and odors have also been received during the past year than in any previous year. In nearly all cases these complaints have been accompanied by requests for examinations of the waters and information as to the character of the water, as well as for remedies to remove the trouble.
The low water in the streams of the State during the summer and autumn has been accompanied by a much greater degree of pollution in those streams which receive sewage and manufacturing wastes than has been at any time noticed since 1887. On this account special examinations have been made of the north and south branches of the Nashua River below Fitchburg and Clinton, of the Neponset River, and of the Blackstone River below Worcester. In the case of the Blackstone River the examinations were unusually complete, including, in addition to the sanitary analysis, the determination of the iron and sulphuric acid which are discharged into the streams by the iron works.
In connection with these investigations an extended series of analyses was made, to ascertain the character and degree of purification effected at the sewage precipitation works of Worcester, and the effect of this treatment on the quality of the water in the Blackstone.
At Framingham several samples of sewage and effluents from the sewage fields have been examined chemically and bacteriologically, with the result of showing that the sewage was very thoroughly purified.
In addition to the systems of sewage disposal just mentioned, the town of Gardner has begun to purify its sewage by filtration through the land, and the city of Marlborough has prepared a disposal area of land which will very soon be ready for use.
The Neponset River is polluted by manufacturing wastes to a greater extent than by sewage, and has brought forcibly before the Board the need of more knowledge as to practicable methods of disposing of such wastes without polluting the streams.
During the summer of 1891 a considerable number of spring waters which are publicly sold throughout the State were collected for examination, and at the same time a careful inspection of the surroundings of the springs was made,
to discover possible sources of pollution. There is a very large sale of spring waters in some of the cities of the State, and there is also a large amount consumed in bottled form, as soda water and other effervescing drinks.
As the result of this investigation, it was found that some of the springs were situated in regions nearly or quite free from population, where the land was not under cultivation, and the chemical and bacteriological examinations of these waters showed them to be of the highest purity. Other springs were situated in populous districts, or had near them direct sources of pollution, and the water gave evidence on chemical analysis that it had, in its course, received a large amount of pollution from the drainage of houses and cesspools. In most of the springs of this character which were examined, the water showed a high degree of purification by filtration through the ground. Although in this condition the water may be considered harmless, it should be borne in mind that spring waters of this kind, which have previously received pollution, contain filtered sewage, and that there is risk in using such waters, owing to the possibility arising at any time of imperfect purification. Out of the forty-three spring waters examined, twenty-three were at the time entirely satisfactory. The remaining twenty waters, which had previously received pollution from a moderate to an excessive degree, were found to have been purified to such an extent by filtration through the ground that at the times of observation they could not be regarded as injurious. A detailed account of these investigations will be given in the forthcoming annual report of the Board.
The Board has given much attention during the past year to the study of epidemics of typhoid fever, to determine whether they were due to infected water supplies.
The question of the cause of epidemics is one of the most important at present before the Board, which is now equipped with expert biologists and chemists who have become qualified by experience to undertake investigations of this character.
In the selection of samples of water for monthly examination during the past year, attention has been largely directed to the effect of storage on surface waters under different conditions. Two hundred and five examinations of samples of water collected from the inlets and outlets of old and seventy-two similar examinations of new storage reservoirs have been made. Many examinations of the character of the water at different depths in reservoirs have also been made, especially as regards the presence and amount of dissolved oxygen, with important results.
It is gratifying to note the increasing confidence with which the work of the Board in regard to water supplies is meeting with sanitarians and engineers, not only within the State but throughout the United States and in foreign countries. Applications for assistance and advice from water boards in Massachusetts are yearly becoming more numerous.
The chemical and biological laboratories have been maintained at the Massachusetts Institute of Technology, where 1,526 samples were examined chemically and microscopically, and many waters were examined for bacteria.
The following classification includes the waters, of which, in most cases, complete analyses were made, and does not include many special investigations, such as the determination of dissolved oxygen at different depths in reservoirs :
Analyses of samples:
From inlets and outlets of old storage reservoirs,
Total from regular water supplies, .
71 250 77 13 11 48
For the coming year the Board proposes to continue the regular monthly examinations of many of the water supplies of the State, selecting as the supplies to be examined those which are used by the larger populations, or which will furnish information of the greatest value. The selections will