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made for drawing water from Bradford Brook in emergencies. The cost of taking a supply from the East Branch, above the junction of Bradford Brook, would probably be somewhat greater than at the place proposed in the application ; but, in view of the better quality of the water, and the less number of dwellings and their distance from the stream, the Board would advise the town to take its supply from the East Branch, above Bradford Brook, rather than at the point proposed.
WOBURN. The water commissioners of Woburn applied to the Board, April 30, 1896, for its advice in regard to the existence of a disagreeable taste and odor in the public water supply. The Board replied to the application as follows:
Boston, June 6, 1896. The State Board of Health has considered your application for advice with reference to a disagreeable taste and odor in the water supply of the city, and has caused an examination of your distributing reservoir to be made, both when the reservoir was full and after the water had been completely drawn off.
Frequent chemical analyses of the water of your filter gallery for several years have shown that the water is colorless and free from taste and odor, and contains very little organic matter, while microscopical examinations show that the water is practically free from vegetable or animal organisms. Examinations of the water of the distributing reservoir, on the other hand, have shown that the water contains at times a large amount of organic matter, and often large numbers of vegetable organisms which impart to the water a disagreeable taste and odor.
These organisms may grow as abundantly and affect the quality of the water as seriously in the colder months of the year as in the warmer months. There is no doubt that the disagreeable taste and odor complained of in the water supply of the city of Woburn is due to the presence of these organisms in the distributing reservoir.
It has been well known for many years that a ground water deteriorates on exposure to light in an open reservoir, such as that in use at Woburn, and experience has clearly shown that the remedy for this trouble is to keep the water from exposure to light from the time it comes from the ground until it reaches the consumer. To accomplish this in the case of the Woburn water works, it will be necessary either to cover the present distributing reservoir or to build a new covered reservoir or tank, which may be of comparatively small capacity and sufficient only for ordinary purposes, if the present reservoir is kept for use in emergencies.
There is no reason to think that, if the quality of the water of your
present filter gallery remains as good as at present, it will support any growth that will cause it to deteriorate, if kept entirely from exposure to light.
SEWERAGE AND SEWAGE DISPOSAL.
The following is the substance of the action of the Board during 1896, in reply to applications for advice relative to sewerage and sewage disposal :
AGAWAM. The selectmen of Agawam applied to the Board, June 10, 1896, for its advice relative to the disposal of sewage from a proposed sewer for the village of Mittineague, into the Westfield River. The Board replied to this application as follows:
Boston, July 3, 1896. The State Board of Health received from you, on June 8, an application for advice with reference to the disposal of the sewage of a portion of the village of Mittineague, situated in the northerly part of Agawam, by discharging it without treatment into the Westfield River. The application was accompanied by a plan showing three possible outlets of the proposed sewer, two of which are into the tail-race leading from the Worthy Paper Company, and a third into the Westfield River, about 100 feet below the outlet of the tail-race.
The Board has carefully considered your application, and has caused an examination of the locality to be made by one of its engineers, and concludes that the disposal of the sewage of this village by discharging it untreated into the Westfield River is permissible for the present.
The sewage should not be discharged into the tail-race, because at times when the mill is not running there is no flow of water in the tail-race, and the discharge of sewage into it would, under these conditions, cause a nuisance.
In discharging the sewage into the river, the Board advises that the outlet of the sewer be carried well out into the stream, so that floating matters from the sewage may not lodge on the shore in the vicinity of the outlet.
ATTLEBOROUGH. A communication was received from the Board of Health of Attleborough, Aug. 29, 1896, stating that they had received a petition from citizens of Attleborough, remonstrating against the discharge of sewage from that town into Ten Mile River, at the same time requesting the Board “ to examine the
locality, and offer suggestions as to a remedy.” The Board replied to this letter as follows:
Boston, Oct. 1, 1896. The Board has caused an examination of the locality to be made by one of its engineers, and finds that the sewer in question discharges into the river just below the bridge at County Street, and that there is another sewer from Attleborough, discharging into the river about 4,000 feet further down stream. The lower sewer outlet is located just above the Dodgeville mill pond, which is said to give off very offensive odors at times. There are several other mill ponds upon the stream below.
From information furnished by you, it is learned that these sewers were originally constructed for surface drainage only, and you estimate that the sewage from about 3,500 people is now disposed of by discharging it directly into the river through these sewers. The Board is also informed that large quantities of ice are harvested from the mill pond below the sewer outlets, and that the river is used as a direct source of water supply by the town of East Providence, in Rhode Island, situated a little less than ten miles below Attleborough.
The discharge of sewage from 3,500 people into a stream of the size of the Ten Mile River would inevitably produce a nuisance, and the condition of the mill pond below the sewer outlets will grow rapidly worse, owing to the decomposition of organic matter deposited from the sewage upon the bottom and sides of the pond. Extending the sewers to a point of discharge further down the stream would simply transfer the nuisance to another locality. The only way by which the nuisance can be avoided is by discontinuing the discharge of unpurified sewage into the river. The disposal of sewage by the present method is not only a nuisance to the inhabitants of Attleborough, but is contrary to existing laws, and is a source of great danger to those using ice and water from the river below Attleborough.
Under the circumstances, the Board considers it very important that a proper method of sewage disposal be adopted, and put in practice without delay. The Board is prepared to assist you in this matter, if you desire, by advising you with reference to any plans that you may wish to submit to it providing for the disposal of the sewage of Attleborough.
BROCKTON. The mayor of Brockton applied to the Board, Sept. 22, 1896, for its advice relative to plans for the drainage of two small districts in Brockton. The Board replied to this application as follows:
Boston, Sept. 24, 1896. The State Board of Health has carefully considered the plans presented by you for the approval of this Board, under the provisions of chapter 309 of the Acts of 1889, providing for the drainage of two small districts in the city of Brockton, one known as the Weston Street district and the other as the Battles Street district, — and hereby approves the plans for the said drainage systems.
BROCKTON. The city engineer of Brockton applied to the Board, Sept. 14, 1896, requesting the opinion of the Board relative to the propriety of fertilizing the growing crops upon its sewage disposal areas “ with frequent doses of sewage.” To this application the Board replied as follows:
Boston, Oct. 2, 1896. In reply to your letter of September 14, asking the opinion of this Board as to the propriety of using the growing crops on your sewage fields as food for human beings, the Board instructs me to say that in its opinion no harm can arise from the use of such vegetables as are cooked before being used, and such grain and other products used for food which cannot come in actual contact with sewage.
DANVERS. The board of health of Danvers applied to the State Board, Feb. 7, 1896, for its advice relative to the disposal of the sewage of certain morocco shops in that town. The Board replied to this application as follows:
Bostoy, July 22, 1896. The State Board of Health received from you on Feb. 7, 1896, an application for advice with reference to the disposal of the manufacturing sewage from the morocco shops or tanneries in Danvers which is now discharged into Crane's River, in which you state that you have under consideration a plan providing for the discharge of the sewage into two large settling tanks, through which you propose to cause the sewage to flow slowly, thereby allowing the heavier matters to settle, and to discharge the effluent into the stream; and you request advice as to whether, by this method, if the tanks are frequently cleaned out, the difficulty of the present system of disposal would not be largely overcome.
Since the application was received the Board has been investigating the character of this sewage, and conducting experiments with a view to suggesting a practicable method of disposing of it in such a manner as to prevent further objectionable pollution of the stream and mill pond. While these investigations have not yet been carried far enough to enable the Board to advise you definitely as to a method of finally disposing of sewage
of this character, the results thus far obtained indicate that it will probably be feasible to dispose of it by some method of filtration after the greater portion of the suspended matter has been removed. It has been found, in the course of the investigations, that much of the suspended matter in the sewage settles out readily upon allowing it to remain practically undisturbed, and experiments at the factory indicate that somewhat more than half of the putrescible organic matter can be removed from the sewage by allowing it to stand for a period of about two hours.
In view of the desirability of keeping as much organic matter as possible out of the stream, and of the probable necessity for the use of settling tanks in connection with any method of disposal that is likely to be adopted, the Board advises, as the first step in overcoming the objectionable condition, that you construct settling tanks of sufficient capacity to allow the sewage to settle for a period of two hours, if it shall be found upon examination that the tanks can be operated satisfactorily by gravity.
Investigations as to the quantity of sewage discharged from the tanneries and the rate of flow indicate that the rate is quite regular, and that the quantity averages about 20,000 gallons per hour during working hours. In order to allow this quantity of sewage to settle for a period of approximately two hours, settling tanks having a larger capacity than those proposed by you will be necessary.
In order to obtain the full benefit that may be derived from the use of settling tanks, it is essential that all of the sewage now discharged into the brook be collected and conveyed to the tanks, and that the tanks be cleaned out frequently. Once in two days may be often enough, though it may become necessary to clean them out daily, so that their capacity may not be greatly reduced, and the length of time allowed for sedimentation materially shortened by allowing the sediment to accumulate to a considerable depth in their bottoms. The tanks, therefore, should be so located and arranged that the supernatant liquid may be drawn off when necessary, and the sludge readily removed at frequent intervals. The tanks should also be designed with a view to the possible necessity of pumping the supernatant liquid to a place of disposal, if this should subsequently be found necessary.
With properly designed tanks, operated with care, a very large portion of the suspended matters which constitute much of the total putrescible organic matters in the sewage can be prevented from entering the pond.
The quantity of sludge to be removed will be large, but not so great that it cannot be removed in carts without special difficulty. The so-called odorless carts may be best adapted to the purpose. The sludge can be disposed of upon filter beds not far from the factory, where areas well suited to the purpose can be found.