METERING AND WATER CONSUMPTION

METERING AND WATER CONSUMPTION

The Problem of Water Waste, and the Elements Affecting Its Elimination—Maintenance of Meters—Tmportance of Complaint Bureau—Methods of Making Waste Surveys—High Bills Caused by Leakage—Centralized Management

(Continued from page 1453, Vol. LXV)

From the foregoing it follows Oak Park people should use more water than the average city regardless of relatively small industrial use. Because in many cities with industrial plants the big users have access to river, lake or well supply and use the city water only for emergency use or for drinking water.

The Waste Problem

It will be noted that the night rate of pumpage will often be from 80 to 90 per cent. of the average daily consumption. This is indicative of much waste. Too much consumption is generally assumed for industrial and other night uses. Such should be determined, not estimated. In Oak Park the night rate, which is considered the waste barometer, was reduced from 56 per cent, to 21 per cent, of the average daily consumption in the four years between 1914 and 1918, inclusive.

The waste problem was attacked along various lines, some of which are not commonly associated with water consumption. The elements substantially affecting waste elimination as developed in the four years between 1914 and 1918, being these.

1st. 100 per cent. meterage.

2nd, Efficient maintenance of meters.

3rd. Efficient complaint bureau, including education of consumers in cause and remedy of needless waste.

4th. Strict collection of high bills due to leakage or waste.

Fig. 4—2 x 5/8-inch Venturi Meter Used with Barometric Manometer for Waste Surveys

5th. Periodical waste surveys.

6th. Comprehensive and workable water ordinance, or rules and regulations, with their strict observance.

7th. Centralized control of the water department.

Meterage

With regard to the first item, 100 per cent, meterage, this means that all water pumped or otherwise delivered into the system is measured at the distributing point no matter where located. Included among the services metered are all municipal buildings, watering troughs, drinking fountains, street sprinkling, water used in parks, water used in the construction of houses and all dwellings regardless of size or character; together with fire hydrants when used for other than fire purposes. It is admitted that in the construction of buildings and in the case of fire hydrants that sometimes more water is wasted than is measured, but it was found that the moral effect of the meter had a great weight in minimizing the unlawful use of water. It is, in fact, a visible permit. Selective metering has been proposed and widely adopted in many large cities in order to reduce expense, but under that basis it would be necessary to meter only 10 per cent, of the Oak Park services, for Oak Park would be considered one of the good controllable districts adapted to periodical inspection, in a city like Chicago, for instance. Under this method, too, the wastage must have taken place before the necessity for stopping it will have become apparent.

Fig. 3—Hose and Hydrant Method of Waste Detection

Maintenance of Meters

The second item, the efficient maintenance of meters, is more important than appears at first glance. Meters should be repaired as soon as possible after being reported stopped or otherwise defective. This condition of the meter is usually detected by the readings, supplemented by observations of the meter reader. All suspicious variations in the readings, both high and low, should be investigated promptly. It has been found that frequent readings taken not less than four times a year, preferably more, gives satisfaction to the consumer in measuring accurately all the water that is used and in giving ample warning of unavoidable excess consumption. The periodical testing of meters, such as once every five years, has disclosed many unsuspected defects caused by undue wearing of parts, or the detection of tampering by the consumer. In Oak Park the test of meters which were used by the private company preceding municipal management disclosed under-registration varying between 10 per cent, and 50 per cent., with an average of 2 per cent, for the entire system. It was also found that in several cases where the bills were not high in spite of very small leakage that the meters did not register leakage as small as 30 gallons per day.

*Excerpts from a paper read before the annual convention of the Western Society of Engineers.

Complaint Bureau

The efficient complaint bureau, and the education of the water consumers are important both for the satisfaction of the water-taker who tends to regard the meter with suspicion and for the peace of mind of the water department executive who realized that it does not pay to antagonize citizens. The systematic handling of complaints is infinitely more satisfactory than adverse arbitrary decisions, or spineless methods of leniency caused by fear of political pressure or favoritism. Every high bill can and ought to be explained. The problem is really one of education. In Oak Park the campaign was begun by utilizing the backs of the water bills for admonitions to the consumer referring to the waste of water. This was supplemented by letters to each complainant with follow-ups in order to test the reduction in consumption after the repair of leaks. The meter readers report all suspicious sounds of running water, although not attempting to trace the cause to save time, and the rest is handled in the office by the complaint clerk. If the consumption is abnormal, a special call is made by a complaint inspector before the waste is brought to the attention of the consumer. It was noted that if notices were sent to the consumer before the investigation, he often repaired the fault and then insisted there must be a mistake or that the meter was incorrect, because there could be no leaks. Hence the adoption of a policy of locating serious trouble before reporting it.

No one in Oak Park has ever been obliged to stint in the use of water in order to receive reasonable bills. In fact the leaks consumed 3 to 10 times more water than the consumers themselves can actually use for all purposes. Our investigators proved that, in every case of that kind, there were toilets leaking at the rate of 1/8 to 1/2 gallon per minute. Sometimes the waste was so small that the watching of the meter did not readily indicate the quantity. Sound is really the best indicator of leaks. This is explained to the consumer who thereafter manages to use all the water he needs, although keeping down the bills. Often a warm meter advocate is thus obtained. It is always a good policy to give the consumer the benefit of the doubt and let it be known that the department is glad to correct errors. In many cases diplomatic cross examinations will uncover sources of waste which the consumers do not realize. It is dangerous to try to prove that the complainant is wrong until you can show him where. Rectify errors promptly. Service is the important element in popularizing the use of meters.

Aside from the waste through fixtures, high bills are caused by leaks in toilets, broken underground pipes in basements, defective toilet valves or ball-cocks, dripping faucets, thermostats, water motors, pumps operated by water power, defective stop-and-waste cocks, leaking valves, breaks in pipes under cement floors, and between walls, water used for cooling food, water wasted to obtain a cool drink, or to procure hot water from defective heaters, children leaving faucets open, lawn sprinkling with hose without nozzles, the flushings of water-closets uselessly after use for purposes for which they are not designed, such as garbage receptacles, leakage through tanks in attics and by allowing water to run continuously in order to prevent freezing, or into washtubs or lavatories for washing purposes, instead of filling the bowls or tubs before using.

Domestic Waste Detector

For causes where the department was unable to determine the cause of high bills owing to the fact that there was no leaking and that the consumer was sure he was not wasting water, a recording detector was designed, which when substituted for the meter gives a graphic record of the consumption for 24 hours or a week. This device consists of a piece of brass pipe one-half inch or three-fourths inch in diameter and 7 inches long, into which are inserted two brass tubes one-sixteenth inch in diameter, one pointed upstream and the other perpendicular to the axis of the pipe. For convenience, these orifices or pitot tubes are soldered into one-eighth inch brass nipples. Two needle valves and strong rubber tubing completes the meter. A special type of recorder with a rapidly revolving chart so that drafts lasting only one-half minute could be detected was constructed which indicated at what time and how long faucets were left open for baths, for washing dishes or clothes, or for lawn sprinkling; how often toilets were flushed, together with a record of all leakage of 1 1/2 gallons a minute or more. In fact, it was found easy to determine at what time the consumers rose and retired and whether they got up during the night or not.

Fig. 1—Recorder and Meter Used for Determination of Rate and Character of Domestic Water Consumption

As shown in the illustration, the short piece of pipe, (which in reality is a brass meter nipple into which are Soldered permanently two pitot tubes) is inserted into the house service either in place of the meter or connected in tandem with it. In all, only two tubes were necessary for the range of consumption which exists between a four-room bungalow and 24-apartment building. In the first experiments the pitot tubes were connected to a mercury U-tube, by means of which rates ranging from less than one-half gallon per minute to 30 gallons per minute were measured by using the one-half inch and three-fourths inch nipples. A camera provided with a revolving sheet of bromide paper, 3 inches wide, was designed and adjusted so that the lens magnified the deflections through a slot about eight-thousandths of an inch wide. A pocket flashlight supplied the illumination, through a condenser and the power was furnished by a single-cell storage battery constructed for the purpose. The only drawback to the device was that the high deflections were beyond the range of the slot, although small leakage was detected which the disc meter failed to record.

Fig. 2—Sample Records Obtained by Means of Recorder or Waste Detector

The next step after fruitless attempts to alter the quantitative measuring device of the displacement so that it would register in gallons per minute, was to design a recorder which could take care of all flows. This new recorder, which is shown in Fig. 1 will detect rates as low as 1 1/2 gallons per minute, and there is no limit to the maximum recording capacity if larger meter tubes with lower center velocities are used. The diaphragm is constructed of one-eighth inch mechanical rubber, and it is surprising to note the power transmitted through the stuffing box. The recovery after a short draft is rapid, even at maximum velocities, as indicated by the accompanying copies of actual records (Fig. 2). The recorder is not extremely accurate but frequent rating by means of the regular meter-testing outfit indicates that it is amply dependable. It has been used successfully in connection with a 2-inch Venturi meter, in making waste surveys by means of the hydrant and hose method, and gives much assistance in determining the varying consumption in the district tested, so that the leakage can be ascertained (Fig. 3).

Plumbers invariably mislead the consumer by failing to appreciate small leaks and by discrediting the meter. Rut Oak Park water-takers are rapidly becoming educated in spite of this. After being shown repeatedly the waste which plumbers failed to locate, and seeing the effect of the stoppage of leaks which, according to the plumbers, could not amount to more than 10 gallons a month,—they refuse to be sidetracked.

Payment of High Bills Caused by Leakage

Regarding rebates on high bills which were caused by leakage, we find that to reduce these indiscriminately is to defeat the purpose of the meters. As stated before, reliance should be placed upon educating the consumer rather than in the practice of allowing reductions in order to avoid adverse criticism or to satisfy some influential citizen. Water-takers easily fall into the habit of depending upon leniency if such is known to be a possible way out of their difficulties. The average consumer can bring the plea of first offense and a promise to be careful in the future. The way it works out though is this: If a rebate is allowed in one case, the tendency of the authorities will be known throughout the community in a short time, and it will be very difficult to enforce payment of other similar bills. If a complainant feels that the Water Department is lax, he will not exert himself to keep his fixtures in repair. If, on the other hand, the water officials are known to be severe and exacting, and absolutely impartial, the majority of the consumers will be satisfied that there is an advantage in being on the alert. The minority, it is true, will complain and accuse the manager or other executive of unfairness, but the fact that everyone has been treated alike and that there are no favorites will permit a very successful operation of the “no reduction on account of leakage” policy. Oak Park speaks from experience. Better to allow a lower rate n the water, approaching the cost per thousand gallons in the case of unavoidable leakage; or else adopt a partial-payment plan or both. But charge for every gallon wasted. The lesson will strike home and be appreciated throughout the community.

Waste Surveys

Waste surveys are very difficult to make and most unsatisfactory in unmetered cities. The speaker has made a number of district waste surveys in many parts of the United States and was always disappointed at finding that the high consumption was due to fixture leakage distributed throughout the system. Periodical waste surveys, however, in a metered city are necessary to locate the underground leakage and reduce the nonrevenue-producing consumption to a minimum.

Method of Making Waste Surveys in Oak Park

In making waste surveys the most convenient method is to make, first, a rough survey of the entire city by means of a pitometer. This is done by isolating certain districts by closing gate valves and measuring the supply through one of the mains left open to serve as a feeder. It is possible on small systems to make the preliminary test by shutting down those districts entirely for a few minutes, especially in the residential sections and note the drop in the rate of consumption as indicated by the recording chart at the pumping station or reservoir or wherever the master meter may be located, providing it is on the distributing system.

It is often found, however, in districts which are completely metered that the velocity of the smallest feed main is so low that it is impossible to obtain an accurate record of the consumption if there are no large leaks. It is then necessary to by-pass the flow of water through a small pipe, 2 inches or smaller in diameter in order to increase the velocity. This is commonly called the hydrant-and-hose method because the most practical way of doing it is to feed from a fire hydrant, without the district, through a fire hose to a hydrant within the district. Oftentimes a regular displacement meter is used and the rate is obtained by noting the readings of the meter at regular intervals. This method is not a very useful one owing to the fact that several drafts may occur during the test. In Oak Park two other methods have been used: One consisting of a 2-inch Venturi meter with a five-eighths inch throat which can accurately record rates from 3 gallons to 50 gallons a minute (Fig. 4). The other is by means of pitometers inserted into short pieces of pipe 2 inches or smaller. Thus a quantity as low as one-fourth of a gallon per minute can be measured (Fig. 5).

Contrary to the usual method of making waste surveys, all tests are made during the daytime, after determining the best hours in which the flow is somewhat steady, for inspection of the Venturi meter at the pumping station. The districts tested varied between onefourth of a mile and 2 miles in length. By being able to watch the rate of consumption, it is rarely found necessary to be on the job for more than half an hour at a time in order to determine the minimum rate of consumption.

The exact population of the district tested is obtained; as well as the average daily consumption through the domestic meters,—the former from the prevailing school census and the latter from the water accounts. Thus an estimate of the legitimate rate exclusive of the underground leakage is determined. In all cases where there is not much leakage the normal pressure is maintained through 600 feet of fire hose. In order to bring the reading within the limits of the manometer where the flow is abnormal the valve on the meter is throttled. In one case a rate of 60,000 gallons per day at 10 pounds’ pressure in a stretch of pipe only one-half mile long was observed, the normal pressure in the mains being 45 pounds per square inch. Subsequent investigation by means of the aquaphone disclosed 6 service leaks which wasted water into the sewer at the rate of 200,000 gallons a day. This meant a leakage per capita rate of 305 gallons per day, while the service meters indicated only a total per capita consumption of 45 gallons, but after the repairs were made the leakage rate per capita dropped to 10 gallons a day.

Water Ordinance

In order to be able to operate the water department efficiently it is necessary that a comprehensive and workable water ordinance be adopted and followed to the letter. All the employees and officials should be able to follow a definite, unswerving policy with a minimum number of loopholes to be detected by skillful lawyers. The water ordinance is either legal or it isn’t. If there be a number of rules which have become a dead letter or are so ambiguous that the executive does not attempt to enforce them because he feels that they would not hold in case of a lawsuit, they had better be tried out immediately or else repealed. The efficiency of a water department is greatly impaired if there is a conflict with other city laws, as in the case of many municipal plants.

Centralized Management

Just a word on the final factor in the control of the water system. It follows from the foregoing paragraphs that all the divisions connected with the operation of large water departments must be under centralized management. It would be better if many municipal plants were made an independent branch of the municipal government. There would then be fewer failures in the operation of municipally owned utilities; failures which are concealed by taxes. There is a little incentive for efficiency in operation, if the superintendent or manager makes a decision, and is obliged to back down because the complainant is able to obtain a concession from another city official higher up, who is not vitally interested in the operation of the department. It is discouraging if the manager has outlined policies which resulted in a saving to the department and finds that the gains made are taken advantage of by some other municipal division which is not operated efficiently; or used because other funds have been exhausted. It is impossible to prevent needless waste of water against the advice of the manager, or if the manager is continually compelled to yield to pressure from some political adherent of the City Fathers.

In the case of complaints on account of high bills, it is disconcerting to attempt adjustments and give satisfaction if the money is collected in one department “shut-oflfs” for non-payment of bills handled in another and the meters read and accounts rendered in either of the foregoing or yet in a third one, all these different divisions being independent and under different executives. Unless all policies originated in the same department, there will be neither co-operation nor co-ordination.

METERING AND WATER CONSUMPTION

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METERING AND WATER CONSUMPTION

Effect of the Installation of Meters Upon the Amount of Water Consumed by the People of a Community —Methods of Controlling Water Waste—Adoption of Sewerage Increases Water Consumption

Hubert P. T. Matte, Superintendent Oak Park, Ill.

IN considering the effect of the installation of water meters upon the consumption of water, and in comparing the usage in various cities, three elements, which may have an important bearing upon the results, are seldom taken into account. These are:

  1. Pressure upon the water system.
  2. Extent of house connections with sanitary sewers, especially the use of bathtubs and waterclosets.
  3. Effective size of mains and services.

Pressure of Water System

When per-capita rates of consumption are published o r mentioned, how often is the average pressure at which the water is supplied included? It is a mistake to omit that item as it is an important one. A city with a higher pressure than another will find that its leakage rate both through fixtures and underground piping will be greater than that of another one which maintains a lower average pressure.

In Oak Park the per-capita rate of consumption is easily varied between one and two gallons per pound change in pressure within the entire range of rates of consumption. That is to say, 10 pounds’ variation either way will make a difference of 10 to 20 gallons per capita daily. Thus the Oak Park rate of 65 gallons per capita at 45 pounds, pressure can be reduced to 45 gallons at 25 pounds. In Niagara Falls where the per-capita rate of consumption was 300 gallons per diem, exclusive of the industrial usage, the writer determined this rate to be from 3 to 5 gallons per capita per pound change in pressure, or 30 to 50 gallons per capita for each 10 pounds. The Niagara Falls consumption was about 6¼ times that of Oak Park and the average pressure was about 60 pounds which accounts for the different limits; but the principle is the same and its importance is clearly seen. The pumping units were designed for a maximum rate of consumption owing to the heavy drafts and as there were no small units provided, the effect of reducing the fixture leakage by the installation of meters and the house-to-house inspection was to boost the pressure at night some 30 pounds greater, or to 90 pounds; and the effect of reducing the leakage was not evident owing to the greater discharge of water through the remaining defective fixtures.

The following table shows one of the uses of water affected by pressure;

A ¾-inch hose 50 feet long with nozzle at 60 lbs. consumes 5,000 gallons per day if in form of jet; at 30 lbs. consumes 3,600 gallons per day if in form of jet; at 55 lbs. consumes 10,000 gallons per day if in form of spray; at 30 lbs. consumes 7,200 gallons per day if in form of spray.

These figures have been obtained from tables prepared by Manager Sullivan of the Nashua, N. H., Water Company.

Extent of Connections with Sanitary Sewers

Another element which is noteworthy in its effect on water consumption is the use of water-closets and bathtubs, although the number of consumers on the line of pipes are often considered in computing per capita consumption. It is seldom that the number of consumers which have the use of faucets only, are separated from those which have all the sanitary conveniences.

In Oak Park from numerous experiments, we determined that the average number of gallons per capita consumed by water-closets where no leaks or waste existed was 20; while under the same conditions the average family consumed 15 gallons per capita through bathtubs. An interesting fact connected with the use of bathtubs is that a person who takes cold baths every morning is very likely to consume 40 gallons per day in this item alone. A psychological effect of the lack of pressure consequently an increase in length of time required to fill bathtubs oftentimes reduces the quantity of water used for baths.

The records from the following cities show the effect of the installation of sewers upon the general water consumption.

In Madison, Wisconsin, the per capita daily consumption m residences with sewer connections was 68, while in residences without sewer connection it was 14.

In Rochester, N. Y., services with water-closets consumed 22 g. p. d. per capita; services with water-closets and no baths 18 g. p. d. per capita; services with waterclosets or baths 14 g. p. d. per capita.

The limited extent of services and sewer connections in foreign cities, thus cutting down the number of outlets for consumption and fixture leakage, is responsible for the low per capita consumption in those cities. From figures obtained three or four years, ago it was noted that the large European cities of over 2,000,000 population had about as many service connections as the average city of 300,000 in this country, while the number of services in foreign cities of about 350,000 population equalled that of our cities of 40,000 population.

*Excerpts from a paper read before the annual convention of the Western Society of Engineers.

Effective Size of Services and Mains

The data on this subject is limited, but difficulty is experienced through loss of pressure by friction from the reduced area of corroded lime-coated service pipes and water pipes filled with algae, crenothrix and tubercles, indicate the importance of the effective size of service pipes and mains on leakage and waste. Water bills on metered premises in which leakage and waste exist often double in size after the renewal of service pipes, both in the ground and in the interior of the house especially when iron pipe has been replaced.

The following table compiled from some experiments conducted by the New York Department of Water Supply, Gas and Electricity, throws more light upon the subject:

Pressure in street mains required to give the tabulated discharge through a corporation cock and 30 feet of lead service pipe.

This table also gives the difference between the pressure at the main and the house side of the service under pressure.

The Use of Water Meters

Having considered the items which affect domestic water consumption as governed by local conditions irrespective of industrial and other usually recognized conditions, we may now discuss the meter question.

Can one imagine a gas company or an electric utility selling its commodity without measuring it? Doubtless though, it is easier to tolerate the waste of water because it is not seen or appreciated. Gas leakage is offensive and dangerous. Wasted electricity is manifested by motion, light or heat; but water disappears unnoticed into the sewers. Yet the speaker knows that in an Eastern city where electric-light current was sold under the flat rate system, electric-light bulbs on numerous porches remained turned on all day long. Queries brought the answer that it did not matter as there was no meter. What can the effect be on the water consumer of this type when the water consumption is not metered? In fact, this same city which was only 28 per cent, metered, the fixture leakage per capita as determined by an extended survey was 205 gallons per day.

Any student of water consumption and waste knows that underground leaks contribute little to the waste included in high per capita statistics. From his experience in Oak Park and elsewhere the writer affirms that the periodical inspection of fixtures in lieu of complete metering is entirely unsatisfactory. When unavoidable leakage will occur through meters, what can be expected when there is no automatic check on the consumption?

In Oak Park it has been observed during the past four years that the annual number of high bills complained of including those places at which the same conditions obtained two or three times a year dropped from 33 to 10 per cent, of the total number of services, due to education of the consumer. Without meters there would have been few complaints and much increase in waste and leakage.

It is most difficult to control fixture leakage by inspection on account of the recurring of the waste as soon as the inspection has been made. In order to do the work that the meter does, it would be necessary to make inspections every month, at least, and in the case of an ordinary residence, it takes about four times as long to make an efficient inspection as it docs to read a meter. In apartment buildings an inspection is a thankless job because all the occupants are seldom at home at the same time. The work, therefore, is usually slighted.

It has been found also that efficient fixture inspection is more objectionable to tenants than meter reading because the inspector has to pry into the privacy of the home. The landlords who dislike to pay plumbers’ bills for the repair poor plumbing are the ones who object to meters. In New York it was noted that after six months’ work the inspector was stopping leaks at about the same rate as the leakage previously stopped was reappearing.

Unmetered water in completely sewered cities with universal sanitary facilities is usually sold at less than cost per thousand gallons.

In Boston with the gradual introduction of meters up to 60 per cent, the per capita consumption dropped from 130 gallons to 90 gallons and in this city vigorous houseto-house inspection was previously practiced. The same may be said of most cities which are metered, although in a few owing to lowered water rates, with too great a minimum allowance, industrial use, and other factors which are mentioned above, the curve is more erratic.

Effect of Meterage in Oak Park and Methods of Controlling Water Waste

For the past five years the water department of Oak Park has made an intensive study of water consumption with a view of reducing to a minimum the waste, and consequently the quantity of water purchased from Chicago. The city is, and always has been 100 per cent, metered, and it has been found that without meters a further material reduction in needless waste would have been an impossibility. In 1913, according to the accepted standards, the Oak Park per capita consumption of 75 gallons was very low, indeed. The night rate of consumption for the total system, however, was 58 per cent, of the average daily consumption, while 20 per cent, seemed to be a fair ratio for a city composed principally of high-class residences with few industries.

As a result of the waste campaign the daily per capita consumption of Oak Park has decreased from 75 gallons in 1913 to 65 gallons in 1918. Yet who can say that Oak Park is not one of the most sanitary cities in the State of Illinois, if not in the whole country?

There are no privies in this city, every house being connected with the sewers. All the consumers have the benefit of water-closets, 95 per cent, have bathtubs; and the bathroom consumed about three-fifths of the water used for domestic purposes. Moreover, every building has a lawn, every street has a grassed parkway on each side of the roadway. From inspection of records of sanitary surveys in various cities with lower and even greater per capita consumption than Oak Park, it was found that the number of premises not connected with the sewers varied between 20 per cent, and 80 per cent, of the total. Every home in Oak Park is connected with the water supply and there are no active wells except two deep wells used by a gas company as a supplement to the city water, and consuming one gallon per capita. In other cities of which we have record, the wells number 5 per cent, to 81 per cent, of the total number of buildings.

(To be continued)

The Public Utility Commission has dismissed a petition of the Princeton, N. J., Water Company to increase its rates 20 per cent, and base charges upon a cubic feet basis.