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WATER SUPPLY AND SEWERAGE.*
[Report required by the provisions of chapter 375 of the Acts of 1888,
entitled "An Act to protect the purity of inland waters, and to require consultation with the State Board of Health regarding the establishment of systems of water supply, drainage and sewerage."]
The following report contains a summary of the work of the State Board of Health during the year 1896, under the provisions of chapter 375 of the Acts of 1888, including the substance of the replies made by the Board to those cities, towns, corporations and individuals which have applied to the Board for its advice relative to systems of water supply, drainage and sewerage, under the requirements of this act, and of special acts which include a clause requiring the approval by the Board of plans and schemes relative to water supply and sewerage, together with a brief statement of the work done at the experiment station at Lawrence and in connection with the examinations of water supplies and rivers.
During the year 1896 public water supplies were introduced in the towns of Hatfield, Rutland, Weston and Winchendon, and important additions to the sources of many existing works were made. At the end of the year 1896 all of the 31 cities in the Commonwealth and 127 towns out of a total of 322 were provided with public water supplies. The total population of the communities having a public water supply is 89.8 per cent. of the total population of the State. There are now but 3 towns which by the census of 1895 have a population exceeding 3,500 which are not provided with a public water supply. The names of these towns, with their respective populations in 1895, are as follows:
6,039 4,055 3,569
The first pages of this report were contained in a report made to the Legislature Jan. 11, *1897 (Senate Document, No. 4). A portion of the report then made, relating to the work done at the Lawrence Experiment Station, is not reproduced, because a more complete account of the work done at this place will be found in a subsequent part of this volume.
The flow of streams for the year 1896, as indicated by the Sudbury River, was slightly less than the normal for twenty-two years. The flow was greatly in excess of the normal in February, March and September, and slightly in excess in October. It was less than the normal in all of the remaining months, the most marked deficiency being in the months of April, May, July and August.
The chemical analyses of the water supplies and rivers of the State and of sewage and effluent from sewage disposal works have been continued during the year, 2,399 samples having been examined. The following is a classified list of the waters examined during the year :
From open and covered reservoirs for the storage of ground
waters, From ground-water supplies, Special investigations of regular water supplies affected by
tastes, odors, etc., . From ponds and storage reservoirs and their inlets, From streams and miscellaneous sources,
Total from regular water supplies,
ham, Marlborough, Gardner, Medfield, etc., From sources used for the supply of picnic grounds, etc., Miscellaneous,
The examination of the microscopic organisms has been continued in the waters which have been examined chemically, as in previous years.
The laboratory for water analysis, which has heretofore been located at the Institute of Technology, was removed at the end of 1896 to rooms set apart for it in the new portion of the State House.
Systems of sewage disposal have been introduced during the year in the towns of Natick and Leicester and at the Westborough Insane Hospital. At the present time there are 11 cities and towns, having an aggregate population of 98,287, in which the purification of the sewage is effected by filtration through beds of gravel or sand, and the sewage of several large public institutions also is disposed of by this method.
References have frequently been made in these reports to the presence of iron in ground waters, and its effect upon the quality of water supplies in which it occurs in excessive quantity. In some cases the quality of the water has been so objectionable as to cause extensive changes in the source of supply, and even an abandonment of the source for this cause, and the problem of improvement of such waters has been the subject of careful investigation by the Board during the past year, and important results have been obtained.
The condition in which the iron exists in water varies in different sources and even in the same source at different times. In one of the towns of the State (Provincetown) it was not feasible to obtain a source of water supply free from iron, and iron has been present in this water in objectionable quantity from the time the supply was first introduced. In this supply iron is found combined with organic matter in such a way that the water is not only objectionable on account of the excess of iron present but on account of the high color of the water.
Water was first introduced into the town in 1893, and, while the quantity of iron at that time was large, it has increased rapidly from year to year, so that at the present time the water contains nearly four times as much as during the first year of its use. Investigations with reference to the purification of this water were begun in the early part of 1896, and have been continued through the year. Experiments upon the filtration of the water through various materials have shown that, by filtration through a filter composed of fine coke, known commercially as coke breeze, practically all of the iron can be removed, and a clear and colorless water obtained which has not been injuriously affected in other respects by the process of filtration. In consequence of the favorable indications furnished by these experiments, the Board has deemed it important to continue the experiments on a larger scale,
and an experimental filter has accordingly been established by the Board at Provincetown. This filter, having a superficial area of one three-hundredth of an acre, was completed and first operated near the end of December, 1896, so that no extended series of analyses showing the results of its operation are as yet available; but the experiments thus far made with this form of filter indicate that a very satisfactory purification of the water will be effected at a moderate cost.
During the summer the attention of the Board was called to the existence of several cases of typhoid fever among the inhabitants of a portion of one of the cities in the State supplied with water from a pond. Upon examination, it appeared that the pond was exposed to pollution from a picnic grove in the vicinity of the water works intake. At about the same time several cases of typhoid fever in another city were traced to a similar resort upon a large pond, which, in this case, was not used as a source of public water supply by a city or town, but visitors were supplied with water for drinking, which was drawn from the pond in the vicinity of the place where sewage entered it from the buildings upon the grounds.
Summer resorts of this kind have become quite numerous in the State, especially in recent years, with the extension of electric railroads; and, in view of the bad sanitary conditions found in the two places referred to, the Board has caused an investigation to be made of a large number of such resorts throughout the State. posed to continue this investigation, and, in cases where the source of water supply and the sanitary conditions are unsatisfactory, to secure their improvement, so far as possible, through owners and the local authorities.
The problem of purification of manufacturing refuse has received special attention, and much valuable information has been obtained from experiments with reference to the purification of sewage of this character, the results of which are given in detail in subsequent pages of this report. Tanneries, paper mills and wool-scouring mills are prominent among the manufacturing establishments which produce large quantities of manufacturing sewage, and a large establishment of either of these kinds may produce as much sewage as a large town, and the organic matter in the sewage of some of these establishments may be several times as great as in an equal volume of domestic sewage. The chemical analyses of manufactur
It is pro
ing sewage have shown that in some cases the chemicals used in manufacturing processes are of such a kind as would destroy nitrification if the sewage should be applied to an ordinary sewage filter directly as it comes from the factory. Ordinary methods of chemical precipitation also have little effect upon some kinds of manufacturing sewage.
A summary of the results of the investigations made during the year is presented in subsequent pages of this report.
Investigations as to the purification of sewage and water at the Lawrence Experiment Station have been continued as in previous years, and in connection with these investigations a large number of samples of sewage and effluent from existing sewage disposal works has been examined. The results obtained from the experiments with filters which have now been in use for several years are of much value in furnishing information as to the permanency of sewage filters of various materials and the best means of maintaining their permanency, especially in view of the increasing number of sewage-disposal plants in the State and the increasing demand for sewerage facilities.
The Lawrence city filter, established in 1893, continues to operate satisfactorily, and the mortality from typhoid fever in the city of Lawrence is the lowest that has occurred for many years, as indicated by the table on a subsequent page.
ADVICE TO CITIES AND TOWNS.
Under the provisions of chapter 375 of the Acts of 1888, entitled “ An Act to protect the purity of inland waters, and to require consultation with the State Board of Health regarding the establishment of systems of water supply, drainage and sewerage,” the Board is required
“ from time to time to consult with and advise the authorities of cities and towns, or with corporations, firms or individuals either already having or intending to introduce systems of water supply, drainage or sewerage, as to the most appropriate source of supply, the best practicable method of assuring the purity thereof or of disposing of their drainage or sewage, having regard to the present and prospective needs and interests of other cities, towns, corporations, firms or individuals which may be affected