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.
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.
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.
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.
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.
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.
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 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.
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.
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.