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ment in the quality of the water could be made by draining the swamps upon the watershed, where necessary. The information at present available, however, is not sufficient to enable the Board to determine whether it is feasible to increase further the reservoir capacity on the watershed, and it would be very difficult to make a satisfactory investigation with reference to this matter at this season of the year.

Under the circumstances, the Board would advise that, before proceeding to take an additional supply from the valley of Mill River, as proposed in your application, you cause an investigation of the watershed of Roberts' Meadow Brook to be made, to determine the feasibility of increasing the storage capacity thereon, and the probable cost of increasing the supply of Northampton in this way, as compared with the cost of obtaining an additional supply from the valley of Mill River.

In this connection the Board would also suggest that you cause an investigation to be made as to the feasibility of obtaining an additional supply in connection with your present works, by diverting into the watershed of Roberts' Meadow Brook by gravity the waters of the upper portion of the North Branch of the Manhan River, about 34 miles above the village of Loudville, and as to the probable quantity and quality of water. to be obtained from this source, and its cost as compared with the other schemes.

The Board will, upon application, advise you further in this matter when you have additional information to present.

PITTSFIELD. The board of public works of Pittsfield applied to the State Board of Health, Nov. 18, 1895, for its advice with reference to increasing the water supply of the city by taking the waters of certain brooks in neighboring towns. The board replied to this application as follows:

Boston, Jan. 16, 1896. On Nov. 18, 1895, the State Board of Health received from you an application for advice with reference to your proposed plans for increasing the water supply of Pittsfield, as follows:

“ The city of Pittsfield, represented by its board of public works, desires the advice of the State Board of Health upon its plans for increasing its water supply in the following manner :

“ Taking and appropriating the waters of Sachem and Hollow brooks in Lanesborough and in Hancock, if their watershed extends into the town of Hancock, and bringing them into the northern part of our water system by means of the construction of a dam or dams at a suitable elevation to cause these waters to flow into our system by gravity; the taking and

appropriating of the waters of Smith and May brooks in the city of Pittsfield and the town of Hancock, and bringing them into the western portion of our water system in the same manner; raising the dam at Ashley Lake, our present storage reservoir, so as to increase its storage capacity.

Subsequently a report of your engineer was submitted, containing the results of his investigations with reference to an additional water supply for the city, with data as to the consumption of water and the flow of many streams in the vicinity, including those at present used for the supply of the city and those proposed as sources of additional supply.

The Board has caused an examination of the proposed sources of supply to be made by one of its engineers, and samples of the water to be an. alyzed.

The results of analyses of samples of water from each of the brooks mentioned in your application, collected by you on Aug. 12, 1895, and of samples collected on Nov. 27, 1895, after heavy rains, indicate that the water of Smith and May brooks is of about the same character as that of Sackett, Ashley and Mill brooks, three of your present sources of supply. The waters of Sachem and Hollow brooks, however, while of much the same quality in most respects, are harder, the hardness of Sachem Brook apparently being nearly as great as that of Hathaway Brook, one of your present sources of supply. The hardness of the water is due to limestone, of which there appears to be a large amount within the watersheds of Sachem and Hollow brooks. On the whole, the indications are that the waters of these brooks may be much harder than is desirable for domestic use.

With regard to the quantity of water that your sources of supply could be depended upon to yield in a dry year after development in the manner proposed, no definite prediction can be made with the information at present available to the Board. The information obtained from the report of your engineer as to the flow of the various brooks during a portion of last summer and fall indicates that in a very dry year the yield of your present sources, viz., Sackett, Ashley, Hathaway and Mill brooks and Ashley Lake, might be increased from fifty to sixty per cent. by the addition of Sachem, Hollow, May and Smith brooks, as proposed. As to the question of raising the dam at Ashley Lake two feet, the experience of the past seventeen years, in five of which the lake failed to fill in the spring, shows with sufficient conclusiveness that with present conditions but little benefit can be derived from raising the dam. If, however, the area of the watershed can be increased, it may be desirable to raise the dam.

Your present sources appear to be capable of supplying the city for the next two years, even if they are dry ones, if the consumption of water is kept within reasonable limits, unless Ashley Lake fails to fill in the coming

spring. In any case, should an emergency arise, a temporary additional supply, sufficient in quantity, is available by pumping water from Sackett Brook at your present temporary pumping station, though it is desirable to avoid the use of this water, if possible, on account of its excessive hardpess. In view of all the circumstances, the Board would advise that you make surveys and investigations in the vicinity of Ashley Lake, to determine whether it is feasible to increase the area of its watershed and how large an additional area of watershed can be made tributary to the lake.

A few years ago the Board advised that West Pond in Washington was not a satisfactory source of water supply, on account of its color and organic matter. These are evidently derived from the vegetable matter of the swamp in and around the pond; and, in view of the fact that your present supply from Mill Brook can be readily supplemented by gravity from Roaring Brook below West Pond, and of the importance to your water-supply system of additional storage-reservoir capacity, it is worthy of examination to determine whether such reservoir capacity may not be obtained and a large drainage area made available by removing the vegetable matter in and around this pond.

It is also suggested that the question of the cost of taking water from Onota Lake by means of a pumping station at its southerly end be investigated.

In connection with these investigations, it is advisable to have the waters of the different available sources analyzed from time to time, so as to determine their general character at different seasons of the year.

With information as to the points mentioned, the Board can advise you more definitely as to the most appropriate source of additional supply for Pittsfield.

PLYMOUTH. The water commissioners of Plymouth applied to the Board, Dec. 10, 1895, for its advice relative to the best method of preventing the bad taste of their water supply, supposed to be due, as stated in the application, to the presence of Uroglena in the water of the source of supply (Little South Pond). The Board replied to this application as follows:

Boston, May 7, 1896. The State Board of Health has considered your application for advice as to whether there is any means of preventing the appearance in Little South Pond of the organism Uroglena, which imparts to the water a disagreeable taste and odor, and your request for advice in general as to the best method of improving the quality of the water supply of the town.

The organism Uroglena was first observed by the biologists of the Board

in the winter of 1891-92, when its presence was discovered in the water of Little South Pond and in two or three other sources at about the same time. Since then it has been observed in several other water supplies in the State, in some of which it has caused serious trouble, as at Plymouth.

The cause of the appearance of this organism in water is not known, and there is no known method of preventing its appearance or growth in the water of a pond or reservoir. In ponds in which its presence has been noted the experience has been that it occurs in the winter season, between October or November and March or April. In some ponds it has been present in nearly every year since it was first observed, though it appears to be present in less numbers and to affect the character of the water less seriously in some years than in others.

This has been the case in Little South Pond, where the organism has been present in greater or less numbers during nearly every year in the past five years, while previous to that time the water is said to have been excellent for many years.

There is, however, a reference to complaint as to the quality of the water in the report of the Plymouth water board for 1877, but the exact cause of the trouble at that time does not appear to have been determined.

With reference to the best method of improving the quality of the water supply of the town, with the information at present available, the Board can advise you only in a general way.

The conditions in the vicinity of the ponds from which your present supply is drawn appear to be very favorable - judging from surface indications - to obtaining water from the ground with freedom, and this is true also of much of the territory about Plymouth. A good ground water, if delivered to consumers without exposure to light either at the source or in a distributing reservoir, is more satisfactory than a surface water, on account of its attractive appearance and freedom from taste and odor. If such a supply can be obtained in the vicinity of Little South Pond, in sufficient quantity to furnish all the water needed by the town at times when the quality of the present sources is unsatisfactory, the present conduit pipes might be used to convey the water by gravity to the pumping station and the town, as at present; and under the circumstances it would probably be more economical to take a supply from this vicinity rather than elsewhere.

If a ground-water supply is introduced, it will be necessary to make such changes in the distributing system as will make it possible to deliver water to consumers without exposure to light.

It might be possible to purify the water drawn from Little South Pond by filtration near the present pumping station, but such experiments upon the filtration of this water as have thus far been made have not been suffi

cient to enable the Board to advise you as to the size of filter or the rate of filtration by which the purification of the water could be satisfactorily effected. If, as a result of experiments, it should be found that it is feasible to purify the water by filtration, it is not unlikely that the cost would, in the end, be greater than the cost of a ground-water supply, if a suitable source can be found near Little South Pond, as suggested. The trouble with the water bas generally been most serious in cold weather, when much care might be necessary to secure satisfactory results by filtration; moreover, while the water supplied to the high-service system might be filtered and supplied to the pumps, as at present, by gravity, pumping might be necessary in order to supply the low-service system under satisfactory pressure, on account of the loss of head in the process of filtration.

Another method by which a water of satisfactory quality might be obtained would be to extend the present intake pipes around Little South Pond to connect with Great South Pond, making it possible to draw water from either source independently by closing the connection between the ponds. While it does not appear, from the limited number of examinations thus far made, that Uroglena has ever been present in the water of Great South Pond, it cannot be predicted that the organism may not appear in the future in this source as well as in Little South Pond, and at the same time. It is not certain, therefore, that a water of satisfactory quality would be obtained by this method at all times. In view of all the circumstances, the Board would advise that

you

have an investigation made, to determine whether it is feasible to obtain a satisfactory ground-water supply from the vicinity of Little South Pond in connection with your present works, taking into consideration the necessity of keeping the water from exposure to light.

Before deciding to introduce a ground-water supply from the vicinity of Little South Pond, it is desirable that you determine whether the capacity of the present sources is sufficient for a considerable time in the future. If the capacity of present sources exceeds but little the present consumption of water by the town, it will probably be best to consider also the question of an additional supply, in connection with the question of obtaining a water of better quality.

The Board will, upon application, advise you further with reference to improving the quality of your water supply when you have additional information to present.

REVERE WATER COMPANY. The Revere Water Company applied to the Board, Nov. 9, 1895, for its advice relative to increasing their water supply by taking the water of a branch of Crystal Brook,

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