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HomeMy WebLinkAbout2769 Report, Committee on Water Supply, no date but presumed 1902The Committee on Water Supply present the following report of progress made by them in matters committed to their charge. At the annual meeting in 1900 the motion being made that the town take measures to enter the Metropolitan Water System, it was voted that the whole matter be referred to a committee with instructions to act with the water commissioners and investigating the subject, and to report at a subsequent meeting. The committee unanimously reported in print at the annual meeting in 1901. At that meeting the sewer commissioners were added to the committee, and enlarging it to eleven members, and the committee was instructed to continue their investigations and to experiment for an additional water supply. One thousand dollars was appropriate for such experiments. At a special meeting held September 12, 1901, the committee reported the progress of the work with recommendations. Said report being now in print with the town reports. The committee was instructed by vote to continue their investigations, to complete the work begun, and to carry out such other measures as were adopted at the meeting. The committee recommended the completion of a well now known as well No.7, the construction of an additional well to take in the Beaverns Spring, known as well No. 8, the construction of a water tight basin for the collection of water from the different source sources and the connecting of these works with the pumps by a large suction pipe. The town appropriate ten thousand dollars for the above purposes. Mr. L. H. Hawes, the engineer whose communication was appended to the report, appeared before the committee and after a long consultation was employed as engineer and to superintend the work. Under his directions the committee advertised for sealed pro- posals for doing the work. Five proposals were received and the con- tract was awarded to T. Stewart & Son Company of Newton. Owing to unavoidable delays this contract was not made until about the middle of October, and the continued dryness of the season made it important to husband water from all our sources of supply and not to disturb the Beaverns Spring until considerably later, so that most of the work has been done under adverse conditions and it is not fully completed. Well No. 6 is completed, the section pipe is laid and wells No. 6 and 7 are connected with the pumps, but the collecting basin is not finished, the severity of the weather rendering it impracticable to work with cement or to complete the grading. As soon as spring opens the work can be finished in a very few days. The committee deemed it important to have all parts of the work done under constant supervision. The difficulties which the con- tractor met, owing to the character of the land, the scarcity of labor and the abundance of water and unfaithful plumbing doubled the time it was estimated it would take to do the work and very materially added to the cost of supervision, so that the entire expense will exceed the appro- priation made by the town and an additional appropriation of two thousand two hundred fifty dollars will be required. The supervision of the work has been very rigid, we are con- fident it has all been well done and that it will accomplish everything suggested in our report. The supply of water from well No. 7 which is an entirely new source, is fully up to the amount expected. Some of the committee have been very confident for years that a very much larger quantity of water would be obtained from the sources of the Seaverns Spring by enlarging the excavation in depth and diameter, or by sinkng a deep well similar to our present deep well No 5. The engineer was not as sanguine as the committee. He thought the quantity would be increased but that this increase would result from direct pumping, by keeping the seams in the rock free and by re- moving the pressure of the bulk of water which must otherwise stand above the openings and as the basin was too small to pump from, it was wise to enlarge it to the capacity of well No. 7. As above stated this has been done. The quantity of water we are now getting from it is without doubt larger than before, but probably only in the manner suggested by the engineer. The strongest claim made by the engineer and by the committee was that the water from the deep well, from the reservoir wells, from the reservoir when it was necessary to use it, and from wells Nos 6 and 7, being all collected in a water tight receiving basin instead of in the open wells Nos. 1 and 2 with their loose connections, we should save a very large amount of water which has hitherto run to waste, and that the water from all these sources, which is excellent, would not be contaminated or discolored by rain or Meadow water or surface drainage. Both of these evils, evident to any one who will give the matter even slight attention, we believe will now be removed and that the quantity and purity of the water will be conserved. We regret that the collecting basin was not finished so that we might have had a practical demonstration of the results before this meeting. As an indication of what we may expect, we recall that early in February for a considerable time the water distributed to the town was pumped largely from wells No. 6 and 7. During this time the water was fine, sparkling and colorless. Since the heavy rains wells No. 1 and 2 have been full so that we are now pumping from these wells alone and the water is highly colored. Carrying out the instructions of the town we experimented during the dry season with wells driven into the woods northwesterly of well No. 6. Six of these wells were connected above ground with portable steam pump, and pumped several days, a few hours each day, the boiler being required for other work the pumping was discontinued and owing to the weather we have not had an opportunity to resume it. The water from these wells comes from a stratum of gravel resting on the ledge about 30 feet below the surface. The water is cool and clear and appears to be good. The superintendent of our works, who did t he pumping, estimated that we obtained at the rate of upwards of 50000 gals. per day. While we were laying the section pipe such an enormous quantity of water boiled up through the mud that we thought it ad- visable to drive other wells in that locality. The experiment showed that there was an abundance of water between the gravel stratum and the surface but of a quality unfit for domestic purposes. Driving through this into the gravel we found sufficient of apparently good quality to justify connecting them and giving them a pumping test. Pipe for this purpose was obtained and is now on the ground, but the recent storms have prevented our continuing the work. The design is to connect ten more wells already driven and showing a con- siderable yield, with the six already connected, to pump these night and day for a week or more, make frequent analysis of the water, and if the supply continues and the water is found to be good, to permanently connect these wells with the suction pipe, so that we may pump from all of them at the same time we are pumping from the new wells, Nos. 6 and 7. If these wells yield only a few gallons each per minute it will be readily seen that the aggregate from sixteen or more will be a considerable addition to our supply. Although we had already nearly exhausted the appropriation for experimental work, we felt justified in going on with the ex- periments so that the connections might be made before the contract work was completed. pumped night and day four months, almost 3000 gallons per hour. During a considerable part of the year it flows at the surface without pumping. At the present time it is flow- ing naturally about six gallons per minute. This apparently indicates that its sources, or some of them at least, are not from the surrounding meadow but from a higher and perhaps distant elevation. The committee have for a long time had considerable con- fidence that it is possible to obtain our larger quantity of water from this well then we have thus far been able to get. It is well known by the town that we are now using on this well the Bacon Air compressor and it will be remembered that in a previous report we detailed the result of our experiment with the Pohle Air Lift, made with the hope that we might obtain better results. The experiment showed that the Bacon method produced better results and we replaced the apparatus. Since that time we have had so much demanding our attention that we have made no further experiments, and, in fact, we rely so largely on this well it is impracticable to experiment with it excepting in the spring months when we have sufficient water without using it. It is well understood that the Air Lift methods require a two thirds submergence, that is, we can lower the water in a well by this method only about one third of its depth. Our well is nearly 200 ft deep and we probably lower the water by continuous pumping not over 75 feet. It is believed that water flows into this well from seams in the rock extending all the way down to the bottom itself. Several reliable firms claim to make deep well pumps that will not only lift the water from any reasonable depth but also at the same time force it to a considerable height. It is claimed to be practicable to pump from the bottom of our well and at the same time deliver the water into our stand pipe. These manufacturers claim that their pumps are of efficient capacity to deliver at the surface from any deep well from 2 to 4 times the quantity that can be obtained from the same well by the Air Lift methods, and at less than half the cost per gallon. One large concern offers to furnish and set up a pump which is guaranteed to be a sufficient capacity to furnish 10000 gallons per hour for $1000, and to pump that amount of water from our well or pump the well dry. And if after a trial it is found not to come up to the guaranty, or if the water gives out, we can return the apparatus, paying only the cost of the experiment, about $200.00. The town has an investment in its water system of upwards of $250000 and we feel that as a business proposition it is wise to spend a considerable amount in trying all reasonable plans that may be suggested to protect that investment before relinquishing it. The report thus far refers only to the work done on the town's land in the vicinity of the present pumping station. At the meeting in September last the Committee reported the result of its experiments in the Roberts Meadow. Five of the driven wells referred to in that report were afterwards connected, a temporary boiler and pump set up, and under the direction of our superintendent pumped for several weeks, the last ten days being continuous, night and day, and under the direction of the State Board of Health. Samples of the water were sent every day to the State Board. The analyses show a slight trace of chlorine, and this also slightly increased as the pumping proceeded. They claim that this indicates animal impurity and the possibility of more serious contam- ination at sometime in the future, perhaps from animal manures spread on distant fields. But the water at the present time is remarkably pure for groundwater and suitable for a domestic supply. They also expressed some doubt as to the quantity of the supply in a very dry season. They do not however condemn the project, although it is evident they are desirous to have us join the Metropolitan System. 7 As to the quantity of water the engineers who are ready to contract with the town as we last reported have no doubt. Mr. Bruce reports he pumped during the last days of the test upwards of one hundred gallons per minute or at the rate of about 150,000 gallons per day from the five wells connected, and that the water was lowered by the pumping only eleven and 2/3 feet below the surface. These wells extend only a third of the distance across the supposed water basin in the meadow referred to. It is proposed to extend them across the whole basin, and there seems to be a little doubt that the capacity within reasonable limits is determined only by the number of wells used. The five wells furnished nearly or quite half as much as we are now using daily. It is easy to estimate the probable amount to be obtained two or three times this number. It seems hardly possible that this source would not be sufficient for many years to supplement the present sources during dry seasons. The committee was instructed to petition the Legislature for an act to authorize the town to take land and water sources in this locality and to negotiate with the land owners for the purchase or lease of suf- ficient land for the required purposes. An Act of the Legislature has been obtained and the town has now authority to act whenever it is deemed expedient. It was not deemed advisable to approach the land owners until the Act referred to was enacted, and this has been so recently done the committee cannot report further at the present time. They recommend no action on this matter at this meeting. For the purpose of completing the work already in hand and for further experimental work above suggested we recommend an appropriation of four thousand dollars ($4000). Geo. W. Whiting Frank D Brown Emmett S. Locke J. Odin Tilton S Myron Laurence Robert P. Clapp A. E. Scott Nathaniel H. Merriam James Elerone[?] Chas. W. Swan Boston, Mass, March 10, 1902. Lexington Water Committee, Mr. A. E. Scott, Chariman, Dear Sir: - I have the following report to make on construction progress of the new work at the pumping station. Owing to the lateness in starting and the very unusual weather during the month of November last which pre- vented the rate of progress usually expected in that month, the work could not be completed in December as planned, thus forcing construct- ion into the winter season when masonry work could only be carried on at favorable stages of the weather. However, the work has been prosecuted with considerable persistency and at the present time both wells have been completed, the section pipe laid and connected with the pumps, the collecting basin which is to take the clear water from the deep well, the reservoir wells and the overflow from the two new wells has been built, roof over, plastered inside and the last layer of concrete on the bottom is now being put in. The necessary pipe connections with this basin have been made and the only work remaining to be done is the filling outside the wall, and some grading at the basin and wells and on pipe line, which can be accomplished when the condition of the ground will permit. As soon as the filling outside the basin wall is done and the plas- tering and concrete have set sufficiently the collecting basin will be ready for use. The two wells are already in operation, measurements of pumping from them alone on the two days recorded resulting as follows:- On one day, pumping at intervals during the period of 10 hours between 9:30 AM and 7:30 PM 96,360 gallons; on the other day, pumping at intervals during the same time 82,425 gallons. March 10 4 pumpings beginning at 9 AM 101,000 gals. -2- During a 24 hour period there would of course be considerably more pumped. The water in well No. 7 will rise about 1 foot higher than in the original spring, and in No. 6 the Seaverns Spring, 3 feet higher than before and can be draughted to a point of 10 feet deeper than originally. In addition to the above work, investigation for a ground supply of water from a system of driven Wells has been in progress and some fourteen wells are down at a place where connection can be made with the suction pipe to the two new dug wells and pumping and then occur from all and the collecting basin at the same time. These wells penetrate through a strtum of clay into a gravel stratum beneath and take water at depths from 26 to 33 feet below the surface. Six of these wells were connected temporarily above the surface and pumped from for a while, the water being delivered into well No. 2 materially aiding in the supply to the town. The balance are to be similarly connected and the whole tested for quantity and quality before being connected permanently below the ground with the main pump suction. With a tight collecting basin for receiving the water as pumped from the deep well, it will be possible to determine the yield of that well and ascertain the relative economy of different methods of pumping its water. It will also be possible to clean out wells 1, 2, 3 and 4 and do the necessary work for protecting them from the highly colored surface water which now gets in; and it will be possible to determine their yield. After the original wells are thus improved and furnished clear water, it is possible that in case additional water is required at any time, to be taken directly from the storage reservoir, it could be improved by passing through the filters already installed at the station provided -3- the quantity were not too great. To do this would require some change in the filtering material, a thorough overhauling of the apparatus and intelligent handling. When necessary to use the stored water even if not filtered, it can be economized by draughting direct from the reser- voir or first receiving it into the collecting basin, instead of into well No. 1 as was the practice last summer, when doubtless the major portion of it was lost into the ground. I would respectfully recommend as an aid to securing greater econ- omy and better results in handling the entire water supply and work in connection with it, that complete daily records be kept in a way that will enable tabulation and comparison of the height of water, sources drawn from, coal consumed, hours of pumping, pump operated, condition of water etc. etc.; no records being now kept that I am aware of. Such information would also facilitate the early discovery of defects and enable application of the proper remedy. Very respectfully, Louis E. Hawes Lexington W. W. Progress Report March 10 1902 Louis E. Hawes 2769