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The conditions are such that the purity of the water of the filter gallery is dependent upon the purity of the water of Little Pond, and, considering the exposure of the latter to pollution from the population upon its watershed, the source cannot be considered a safe one for drinking purposes. Moreover, there is a dense population upon the territory east of the pond, sloping toward the filter gallery, from which a portion of the water of the filter gallery is doubtless derived, and the presence of this population in its vicinity is also a menace to the purity of the water.
In view of all the circumstances, the Board does not advise a further extension of the works for collecting ground water in the vicinity of Little Pond, since neither the quantity obtainable nor the quality is likely to be satisfactory, but advises that you take the whole subject of your future water supply into consideration, with a view to securing a source from which an adequate supply of good water can be obtained to meet the reasonable needs of the town for a considerable time in the future.
It is understood that the town has the right to take water from Great Pond in Randolph and Braintree; but, since a good ground water would doubtless be more satisfactory, before deciding as to a source of supply it is very desirable to determine first whether it is not possible to obtain an adequate supply of ground water from some suitable source.
BRAINTREE. The water commissioners of Braintree again applied to the Board, Aug. 21, 1896, for its advice relative to a “temporary arrangement” for an increase of its water supply. The Board replied to this application as follows:
Boston, Sept. 3, 1896. The State Board of Health received from you, August 25, an application for advice with reference to obtaining an additional supply of water for the town by putting in tubular wells on the shore of Little Pond, near your present pumping station, in which you state that, pending action by the town with reference to the recommendations contained in the reply of the Board to a previous application, there is an urgent necessity for temporarily supplying more water to the town than can be obtained from the present filter gallery. Accompanying the application was a plan showing the proposed location of test wells along the shore of Little Pond, just north of the present pumping station, the nearest well being distant about 75 feet and the farthest 225 feet from the pumping station. As indicated upon the plan, the wells will be 17 feet from high-water mark in Little Pond.
The Board has carefully considered this scheme, and concludes that it is
probable that a larger supply could be obtained temporarily from the wells and filter gallery together than from the filter gallery alone; but, as it appears that the capacity of this pond and its watershed for supplying water to the town of Braintree in a dry year has already practically been reached, the increase of supply obtained by drawing from the wells would be only temporary, and should a dry year occur, the supply would become exhausted.
With regard to the quality of the water to be obtained from the proposed wells, it may be said that, so far as can be judged from a single analysis, the indications are that it will not differ materially from that of the present filter gallery; and, if the water entering the wells by filtration from the pond should be imperfectly filtered, as there is reason to expect that it may be, the water of the wells will be exposed to danger of pollution from the population upon the watershed of the pond. The sanitary conditions at present existing in the region in which it is proposed to locate the wells are bad, but the conditions could be considerably improved by careful sanitary care of the watershed. Considering the urgent need for an additional supply of water while you are seeking a better source of supply, the Board considers that it is permissible to obtain it in the manner proposed, if the precautions suggested are carefully observed.
COHASSET. The Cohasset Water Company applied to the Board Nov. 14, 1896, for its advice relative to an additional water supply, to be taken from the ground in the neighborhood of a small brook in that town. The Board replied to this application as follows:
Boston, Dec. 5, 1896. The State Board of Health has considered your application for advice with reference to obtaining an additional supply of water for Cobasset from the ground in the vicinity of a small brook west of Sohier Street, and has caused an examination of the locality to be made by its engineer, and samples of water collected by you from two of the test wells in this locality to be analyzed.
The water of both samples was found to be softer than that furnished by your present wells, but the water from one of the wells (No. 10), which is located a considerable distance south of the railroad and east of the brook, has at some time been polluted and subsequently purified by its passage through the ground. The sample from the other well (No. 7), which probably represents more nearly. the average quality of the water of this region, was much softer and of better quality, and in its present state would be a more satisfactory water for domestic purposes than that furnished from your present works.
The information obtained from the tests thus far made is not sufficient to make it possible to predict with accuracy the probable amount of increase in your supply that would be obtained by the use of wells in the localities proposed. From information furnished as to the height of water in the test wells, it appears that the ground water in this vicinity is probably already influenced by the pumping from your present wells. By lowering the ground water here by means of additional wells, it would be possible to draw a somewhat greater quantity of the water stored in the ground, and to cause the water to percolate toward the wells from a larger area than at present. It is possible, also, that water from the brook filters into the ground to some extent under present conditions, and filtration from this source might be increased somewhat by lowering the level of the ground water in the vicinity of the brook; but it does not seem likely that there will be any considerable increase in the quantity of water that will be obtained from this source. It appears, from the results obtained from the test wells, that ledge is found nearer the surface at this place than in your present wells, and that the gravel stratum in most of the wells is quite thin. These indications are not favorable to a large yield from the proposed source, and are not conclusive as to whether the additional supply obtainable in this place will be sufficient to warrant the expense of connecting it with your present works, even though the cost would be small.
It is desirable, therefore, before incurring the expense of constructing permanent works in this locality, that you cause a pumping test to be made by pumping continuously from a number of wells with a steam pump for a period of at least two weeks, with a view to obtaining some more definite evidence as to the probable yield from this source. The capacity of your present works is insufficient for the present needs of the town in the summer season, and it is very desirable that in constructing additional works you secure a supply that will be adequate for pre ent needs in a dry season and sufficient to meet the reasonable needs of the town for a considerable time in the future. Unless, therefore, you find upon further investigation that the quantity of water which these wells will furnish will be a material addition to your present supply and furnish a sufficient quantity of water to meet the needs of the town in connection with your present works for several years, it will probably be more economical to secure in the beginning a supply from some adequate source.
FRANKLIN. The selectmen of Franklin applied to the Board, . Aug. 1, 1896, requesting the Board “ to investigate the sources of the public water supply of Franklin, and report their finding." The request was made on account of a communication from one of
the citizens of Franklin, asking for an investigation as to the quality of the public water supply. The Board replied to this application as follows:
Boston, Oct. 1, 1896. The Board has caused an examination of the sources of supply to be made and samples of the water to be analyzed. The sources in use at the time of examination were two wells, located on the easterly side of Mine Brook, distant about 50 feet from high-water mark in the brook, and a pond, known as Beaver Pond, on the westerly side of Mine Brook.
There is a large population in the village of Franklin upon the territory from which a portion of the water which enters the wells is evidently derived, but no buildings are found within 700 feet of the wells at the present time. Analyses of the water show the presence of some of the mineral matters due to the sewage entering the ground in the populated portion of the territory draining toward the wells. It is probable, also, that a portion of the water is derived by filtration from Mine Brook, a highly polluted stream; but the analyses show that such polluted waters as may have mingled with the ground water entering the wells have been thoroughly purified in their passage through the ground, and at the present time the water is safe for drinking. The indications are that the population will increase upon the territory sloping toward the wells, and in that case the quality of the water will tend to deteriorate; but if no houses are constructed nearer the wells than at present, and if the sewage is removed from the district, further deterioration can probably be arrested.
As already stated, it is probable that a portion of the water entering the wells is derived from Mine Brook by filtration through the ground. The experience with wells in similar situations has sometimes been that after a longer or shorter period of use the quality of the water deteriorates, owing to imperfect filtration of the water passing through the ground from the neighboring pond or stream to the well; and, while there is no evidence that any of the water entering the wells of the Franklin Water Company up to the present time has been imperfectly filtered, it is very desirable that the discharge of domestic or manufacturing sewage into Mine Brook or its tributaries above the wells be prevented.
The analyses of the water of Beaver Brook show that it is highly colored, and contains at times a large amount of organic matter in the form of microscopical organisms of a kind which have been known to produce disagreeable tastes and odors in the water of many other ponds and reservoirs in the State. These conditions affect the appearance and taste of the water, but with our present knowledge are not regarded as dangerous to the health of those drinking it. The watershed of the pond contains so
small a population that the danger of the pollution of the water from sewage discharged upon the ground within its watershed is very slight. From an examination of the pond and its surroundings, it appears that between the pond and Mine Brook there is an area of low and swampy land which is apparently flooded at times of high water in the brook, and the outlet from the pond to the brook passes through this low land. It is not feasible to determine, from the limited examination which the Board is able to make, whether it is possible for the water from the brook under certain conditions to enter the pond. If brook water should enter the pond, it would enter on the side where the intake is located, and there would be great danger that this polluted brook water might be drawn for the supply of the town. In order to determine whether this is possible, a careful survey and investigation will be necessary, and the Board advises that such an investigation be made. If it should be found that brook water can, under present conditions, enter the pond, it may probably be kept out by constructing a dam, and, if necessary, a dike, at the outlet of the pond and along its easterly shore; but if these works should be found necessary, it would be well to consider whether it may not be possible to obtain a more satisfactory supply than the pond furnishes, by constructing a well at some suitable locality in the vicinity of the town where a satisfactory supply of ground water can be obtained.
It is possible that a portion of the complaint as to the quality of the water supplied to the town may be due to the growth of microscopical organisms in the open tank. Trouble from this cause could be avoided by covering the tank, and it is advisable that this be done if the use of ground water is to be continued.
HARVARD. Messrs. Hildreth Bros. of Harvard applied to the Board, June 26, 1896, for advice relative to a proposed water supply for a factory and a few dwelling-houses in that town, to be taken from a well north of the common. The Board replied to this application as follows:
Boston, Aug. 6, 1896. The analyses show that the water is hard and has at some time been polluted, but subsequently well purified by its passage through the ground. In its present condition the water is suitable for drinking and other domestic purposes, though the hardness will probably make it somewhat unsatisfactory for washing and for use in boilers.
The information furnished by you indicates that the quantity of water which the source of supply will yield is limited, but is probably sufficient for the supply of the factory and houses mentioned in your application.