NORTHFIELD WATERWORKS SYSTEM

NORTHFIELD WATERWORKS SYSTEM

Preliminary Work on New Reservoirs, Northfield. Vt.First Stage of Covering Reservoirs, Northfield. Vt.Second Stage Reservoirs Covering. Northfield. Vt.Showing Part of Completed Roof of Reservoirs. Northfield, Vt.

A large portion of this article by F. L Fuller, C. E., Boston, appeared in FIRE AND WATER ENGINEERING of June 19. Since that time the accompanying illustrations have been sent, which will be appreciated by the readers of this journal. In order, therefore, to make them all the more valuable, so much of the article as is illustrated by them is reproduced: “The newly completed waterworks system at Northfield, Vt., is a good example of an efficient, modern, and in every way satisfactory municipal equipment for the domestic supply of its inhabitants and the protection of their property. The supply is from springs issuing from elevated hillsides, some of which are more than 1,000 ft. above the town. The watershed of these springs contains only a very sparse population, which is probably decreasing, being the occupants of a few scattered farms. The present supply, which is not entirely developed, is probably sufficient for some years to come, if used through meters, as it unquestionably should be.” The writer, however, points out that it will not be easy for the people, who have been accustomed to the use of water under very wasteful condi tions, to “accept the limitations of the meter system, forgetting that the purchase of waterrights, and collecting, storing, and distributing the water they are using, have involved much expense,” all the more that they are now offered facilities for fire protection and the like in addition to a domestic supply. As the village is largely composed of wooden buildings, liable at any moment to be swept by fire, the advantages accompanying the new system are not only obvious. but are worth paying for—to say nothing of the large reduction in fire insurance rates. The “supply can be further increased by connecting some as yet unused springs, and, possibly, by excavating wells in porous material, provided such can be found in sufficiently large areas and of suitable depth. There are two sets average pressure at seventy-seven hydrants is 130 lbs, per in., so that the system is certainly strong in this respect. The size of the distribution mains, which are of cast iron, is shown on the map. But little 4-in. is used, and only nine out of seventy-seven hydrants are on mains smaller than 6-in. in diameter. These nine hydrants are in the lower part of the village. where the pressttr – is large and the houses are low. All street mains have a cover of 5 ft. 6 ins. The 6-in. supply pipe from the intake to the distribution system is laid through the woods aid has a cover varying from 2½ to 4 ft.: but. as the water is constantly in motion, there is no danger of freezing. The system is well supplied with gates and hydrants, as will be seen by examining the map. Hydrants average about 450 ft. apart. There are 6.6 miles of pipe in the distribution system, and 1.5 miles in the 6-in. Whetstone brook supply line, which connects the former with the intake already mentioned—making a total of 8.1 miles. The total cost of the system was alxmt $84,000.” The nearness of the reservoir to the village (they are only yoo ft. from the distribution system) involves hut little waste pipe, and less frictionloss in the 12-in. main between the reservoir and the point at which a tire may occur. of springs connected with the distribution system. as shown on the map—one. furnishing the larger supply, at the northerly end of the village. Much of this water is furnished direct to the consumers before going to the reservoirs. These springs are all brought together in a covered concrete intake. 6 ft. in diameter, provided with a screen, an overflow pipe, and the necessary valves. It is at an elevation of 72.5 ft. above high-wat r level in the reservoir. This difference in level is sufficient to overcome the friction loss in the 6-in., 8-in., 10-in. and 12in. pipe between the intake and reservoir. The other, or southeasterly system of springs, is piped directly to the reservoirs, as shown on the map. By means of a bypass the water from these springs can flow directly to the village, without entering the reservoirs, or can be allowed to enter either, or both, as may be desired. The reservoirs, as shown on the map, are two in number, placed near each other and at the same elevation. They are about 46.3 ft. internal diameter and 20 ft. deep, having a capacity of about 250.000 gals. each. They are built of concrete, circular in form, and covered with a dome-shaped roof of the same material. The only reinforcing is a steel hand irhbedded in the top of the concrete circular wall to resist the thrust of the roof. These reservoirs can be used separately or in conjunction. Each has a waste, or overflow-pipe, and the waste can he regulated to occur mostly at the intake or reservoirs. as desired. The reservoirs are both built in solid slate rock, which underlies most of the hills in this section. Some of this excavated slate was used in the reservoir walls, forming boulder concrete of an excellent character. The elevation of the reservoirs is greater than is required even for fire-service in the village: hut. to protect the property of Norwich University, which is built on land considerably higher than the village, it was necessary. The

Governor Hughes, of New York State, acting on complaints that have borne no fruit through several State administrations, has begun a thorough probe into the pollution of State rivers and streams by pulp and sulphite mills. As an initial step, he ordered State Commissioner of Health Porter to make an investigation into the complaints that the discharge of acids into the river from the mills at Fort Edward, Glens Falls, and other points in the vicinity constitute a continued nuisance and menace to health. Riparian owners below Fort Edward went before Governor Hughes several weeks ago and declared that the acids from the mills had killed all the fish in the river and made the water unfit , for agricultural or domestic purposes.

NORTHFIELD WATERWORKS SYSTEM

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NORTHFIELD WATERWORKS SYSTEM

The newly completed waterworks system at Northfield, Vt., is a good example of an efficient, modern, and in every way satisfactory municipal equipment for the domestic supply of its inhabitants and the protection of their property. Conditions vary in different localities, and, while it is almost always possible to secure some sort of a supply and store a certain reserve in a natural reservoir or in an artificial structure and distribute it under a more or less efficient head, there is a wide range in the real worth of waterworks systems. It is almost universally true that it is impossible to get something for nothing, and the value of any such system or any public improvement depends largely upon the thought, ability and money put into it. The province of the waterworks engineer, properly fitted by education and experience, is to take into consideration all the existing conditions, physical, financial, as well as any other peculiar to the case in hand and, with wise judgment as to the future, design and execute that which shall in the best possible manner fulfil all the needs of the community. Good ability and experience in design and supervision of construction are generally fully worth all that is paid for such service. Mistakes of any kind are unsatisfactory and expensive to rectify. Works are not built for today alone, and the expenditure of the necessary money at the time the work is done, although it may seem large, to secure the desired object in a satisfactory manner, will entail less future criticism than a scrimping of money and poor and insufficient construction. Almost every waterworks system is weak in some particular. The supply of water, although the best obtainable, may be of poor quality, or insufficient in amount. The topographical features may be such that it is impossible to secure a satisfactory elevation for a distributing reservoir and a standpipe, possibly of small diameter, requiring almost constant pumping, may be the only alternative. The small amount of money available may require the laying of distribution pipes of so small a diameter as to develop great friction losses when large quantities of water are used within a limited area in case of fire. As time goes on corrosion (if of cast-iron) still further reduces their carrying capacity to an appreciable degree. Possibly it is better to have a poor, insufficient system than none at all; but it is a serious question whether it would not be better to wait till such a time as a more satisfactory system could be installed. The poor system blocks the way for a better one, and the community, in the end, may be the loser on account of having built it. True wisdom would dictate the building of works a little better, and on a more liberal basis than the actual needs at the time demand. Twenty or twenty-five years is, perhaps, not too long a time to look forward to in designing a plant for even a moderately growling community. A glance backwards of a similar length of time will show marked changes in almost any city or town. The very fact of the introduction of a liberal supply of wholesome water, under sufficient pressure to afford firstrate fire protection, is an important factor tending to promote growth and business prosperity. This has been exemplified in cases almost without number all over this country. It follows, therefore, that the forward look should have in mind a somewhat greater degree of expectation than the backward look would warrant. Tt is not claimed that the Northfield system is perfect; but it is strong in nearly all of the points previously enumerated. The supply is from springs issuing from elevated hillsides, some of which are more than 1,000 ft. above the town. The watershed of these springs contains only a very sparse population, which is probably decreasing, being the occupants of a few scattered farms. The present supply. which is not entirely developed, is probably sufficient for some years to come, if used through meters, as it unquestionably should be. This community, like many others in New England, has for a number of years past been supplied by private aqueduct companies. Each family has had wffiat is called a “gauge-stream”—that is, all the water which will pass through a very small aperture in a thin disk. The water flow’s through this opening into a tank having an overflow. It is needless to say that but a small proportion of the water is actually used, the remainder being wasted. The discharging capacity of these gauges increases with use, a very slight enlargement of the size of the aperture, due to the wearing effect ot the stream of water, augmenting materially the yearly, or even daily flow. One of these gauges at Northfield was found to pass 570 gals, per twenty-four hours. It is naturally difficult for persons who have used water under such wasteful conditions to accept the limitations of the meter system, forgetting that the purchase of waterrights, and collecting, storing and distributing the water they are using, have involved much expense. It is not borne in mind that the old aqueduct system furnished them no fire protection, while the cost of a modern system thoroughly equiped for such service is probably three times as great as that of a system adequate for domestic service alone. The Northfield supply can be further increased by connecting some as yet unused springs, and, possibly, by excavating wells in porous material, provided such can be found in sufficiently large areas and of suitable depth. There are tw’o sets of springs connected with the distribution system, as shown on the map—one, furnishing the larger supply, at the northerly end of the village. Much of this water is furnished direct to the consumers before going to the reservoirs. These springs are all brought together in a covered concrete intake, 6 ft. in diameter, provided with a screen, an overflow pipe, and the necessary valves. It is at an elevation of 72.5 ft. above high-water level in the reservoir. This difference in level is sufficient to overcome the friction loss in the 6-in., 8-in., 10-in. and 12 in. pipe between the intake and reservoir. The other, or southeasterly system of springs, is piped directly to the reservoirs, as shown on the map. By means of a bypass the water from these springs can flow directly to the village, without entering the reservoirs, or can be allowed to enter either, or both, as may be desired. The reservoirs, as showui on the map, are two in number, placed near each other and at the same elevation. They are about 46.3 ft. internal diameter and 20 ft. deep, having a capacity of about 250,000 gals. each. They are built of concrete, circular in form, and covered with a dome-shaped roof of the same material. The only reinforcing is a steel band imbedded in the top of the concrete circular w-all to resist the thrust of the roof. These reservoirs can be used separately or in conjunction. Each has a waste, or overflow-pipe, and the waste can be regulated to occur mostly at the intake or reservoirs, as desired. The reservoirs arc both built in solid slate rock, which underlies most of the hills in this section. Some of this excavated slate was used in the reservoir walls, forming boulder concrete of an excellent character. The elevation of the reservoirs is greater than is required even for fire-service in the village; but, to protect the property of Norwich University, which is built on land considerably higher than the village, it was necessary. The average pressure at seventy-s .*ven hydrants is 130 lbs. per sq. in., so that the system is cor tainly strong in this respect. The size of the distribution mains, which are of cast iron* is shown on the mao. But little 4 in. is used, and only nine out of seventy-seven hydrants are on mains smaller than 6-in. in diameter. These nine hydrants are in the lower part of the village, wh re the pressure is large and the houses are low-. All street mains have a cover of 5 ft. 6 ins. The 6-in. supply pipe from the intake to the distribution system is laid through the woods and has a cover varying from 2½ to 4 ft.: but, as the water is constantly in motion, there is no danger of freezing. The system is well supplied with gates and hydrants, as will be se-m by examining the map. Hydrants average about 450 ft. apart. There are 6.6 miles of pipe in the distribution svstem. and 1.5 miles in the 6-in. Whetstone brook suoplv line, which connects the former with th” intake already mentioned—making a total of 8,1 miles. The total cost of the system was about $84,000. One of the satisfactory results of installing the system has been the large reduction in insurance rates, showing it has approval of the fire underwriters. The village is largely composed of wooden buildings, although within a fewyears several substantial brick blocks have been erected. Without an adequate system of fire protection, the community has been liable at any time to be swept by the flames. Some of the important features of this system are: The excellent quality of the spring water, which is delivered in a short time to the consumer, a portion only being stored in covered concrete reservoirs. The water, thus stored, is warmer in winter and cooler in summer than w-ould otherwise be the case, which is very desirable, there being less freezing of mains and service-pipes, and the water requiring but little, if any ice for drinking purposes in the warm weather. The water being stored in the dark, there can be no microscopic organisms to injure the water by their growth and decay. The distribution mains are of large size, when the high pressure is considered. Many systems under far less pressure have very much smaller pipes. The advantages of size and pressure will be apparent in later years, when corrosion has begun to take place, and consumption has increased, or the demands for fire protection are greater. The pressure is unusually good, and cannot fail to do excellent fire-service, whenever it is required. Where the pressure is unusually heavy, a valve between the hose-nozzle and the hose will regulate the pressure. The number of hydrants is comparatively large, they being on an average only 450 ft. apart. The supply of gates is liberal, thereby furnishing the means of readily controling the system. Another fact, advantageous to the town, is that the pipe was bought at a price about $10 per ton less than it can nowbe obtained, and yet another is that the reservoirs are only 900 ft. from the distribution system, involving but little waste pipe. The nearness of the reservoirs to the village means less friction loss in the 12-in. main between the reservoirs and the point at which a fire may occur