Plumbing and The Water You Use

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Using Your Water Meter

Obviously, the primary use for a water meter is to let the water company know how much water you use so they can charge you for it. There are, however, a few other uses for your water meter.

Areas with a metered water supply can be man aged more efficiently than those without water meters. The water company, as well as the city; county, state, and federal governments, can use water meter figures to determine how much water is being used by customers and how much is being wasted by evaporation or leaks in the system. They can determine how much is being used by various customer groups: farmers, industries, house holds, geographical areas, or any other group they need to know about.

This information is valuable in the intelligent planning of future water needs in any area. It allows planners to base their recommendations for new facilities on actual water usage rather than on guesses and estimates, which they would have to use if there were no meters. Many of the political controversies about water in New York City could probably be settled much more quickly and easily if that city had water meters to prove what was happening with the water after it entered the city. Tracking water usage. You can use your meter for more than just “checking up” on the water company’s billing. You can determine how much of your water is used for any one purpose, such as the garden or your teenager’s 20-minute morning showers. Especially in times of water shortage or drought, knowing how much water you use for bathing, laundry; washing the car, or filling the swimming pool can aid you in planning and conservation.

To determine the amount of water used in any operation — taking a long shower, for instance — turn off all the water in the house and garden. Read your water meter, as described in the box, and write down the number. Then go take your shower. When you have finished, read the meter again. Subtract the first number from the second, and the answer will be the amount of water you used, usually in cubic feet. There are 7.5 gallons in a cubic foot, so to find the number of gallons you used, multiply the cubic feet by 7.5.

To find out how much your showers are costing you each month, look at your water bill to see how you are charged. Most bills list one or more fixed costs, like fire protection or capital improvements, and one cost based on how much water you used. The water-use cost is usually an amount between 30 and 60 cents for each 100 cubic feet.

Multiply the cubic feet of water you used for each shower by the number of showers you take each month to get the cubic feet of water you use each month for showers. Then, divide this figure by 100 and multiply by the rate per 100 cubic feet.


Water used for one shower = 2.7 Cu. ft. (20 gals.)

Number of showers per month = 36

Cost per 100 Cu. ft. = $55

Step 1. 2.7 x 36 = 97.2

Step 2. 97.2 ÷ 100 = .972

Step 3. .55 x .972 = .5346

= = =

Reading a Water Meter

In most areas, water is measured in cubic feet and you are charged for water on the basis of how many hundreds of cubic feet you use. Three types of meters are commonly used in the United States for home water consumption measurement. One of them has a direct digital readout that resembles the odometer on your automobile. This kind usually has a sweep needle that measures one cubic foot with each revolution. The one-cubic-foot dial is divided into tenths.

The second type has a large dial and also a sweep needle that indicates the passage of one cubic foot of water with each revolution. In addition, it has five small dials that all move clockwise. Each is divided into tenths, and each is labeled for the number of cubic feet it records with each revolution—IU, 100, 1,000, 10,000, and 100,000, To read this kind of meter, look at the 100,000 dial first and note the smallest of the two numbers nearest the needle. Then note the reading of each of the other dials in descending order, the last digit coming from the 10 dial.

The most common type of water meter is the one with six dials. It operates and is read the same way as the one with five small dials except that the dials alternate clockwise and counterclockwise in their motion. Look carefully and be sure to note the smaller of the two numbers nearest the needle on each dial. The one-foot dial is usually not marked with ten divisions on this type of meter. This dial is mainly intended to show the passage of water, like when you are trying to detect a leak.

All of the meters shown here have the same reading, 371,940 cubic feet.

Most water companies charge by the hundreds of cubic feet of water, so they only read and record the first three digits from the meter. On your bill you will find something like this:

Prior reading=350

Present reading=371

Consumption in 100 cu. ft. (CCF)=21

You are then charged for 2,100 cubic feet of water at the prevailing rate.

ill.8 Most water meters register cubic feet and run continuously from when they are installed. To tell how much you’ve used in a month, take a reading at the beginning and end of I1 the month and subtract.

= = =

The water for your showers costs you a little over 83 cents each month.

Unless you take only cold showers, the cost of water you use isn’t the total cost of a shower. You must also pay the cost of heating the water. The gas company Charges you for therms, not by the volume of gas you use. A therm is 100,000 Btu’s (British thermal units). A Btu is the amount of heat it takes to raise one pound of water one degree Fahrenheit.

To figure the cost of heating your shower water, you multiply the number of gallons (36 x 20 = 720 in our example) by 8.3 (the number of pounds in a gallon) and this total by the number of degrees Fahrenheit you raise the temperature of the water. If the Cold tap water temperature is 50 degrees and you like your shower water at 105 degrees, this number would be 55. This total is the number of Btu’s you have used. Divide this by 100,000 to get therms and multiply the therms by the gas company rate per therm (let’s say by $0.50).


Step 1. 720 x 8.3 x 55 = 328,680

Step 2. 328,680 ÷ 100,000 = 3.29

Step 3. 3.29 x 0.50 = 1.645

It costs a little over $1.64 to heat the water for your showers each month. Add this to the 53 cents for the water, and you find your showers Cost you $2.17 per month.

Detecting hidden leaks. Another use for your water meter is to determine whether or not you have a hidden leak somewhere. A soggy spot in your garden, a wet place on a wall or ceiling, or an exceptionally large water bill can all indicate a leak. If you have suspicions but can’t find an obvious leak, try this simple test. Turn off all the water everywhere in the house and garden. Watch the needles on your water meter carefully. If you see any of the needles moving, you have a pretty big leak. If none of the needles is obviously moving, use a felt-tipped pen to mark the exact location of the large needle. If there is no “large” needle, mark the small one labeled “one foot.” Don’t turn on the water for any purpose—or flush the toilet—for the next hour or two. Check the meter occasionally; if the needle moves in that period, you have a leak. To see how much water you are losing from the leak, use the same method described for finding out how much water you used for showers.

If the one-foot needle moves across three marks on the circle in an hour, you have used three-tenths of a cubic foot in that time. Your leak is wasting over 216 cubic feet per month—that’s over 1,500 gallons, which is quite a few showers.

If you suspect a leak, but do not have a water meter to check it out as described, you can find it in other ways. Leaks tend to make noise. Sometimes it’s a hiss and some times it’s a gurgle. Put your ear against an exposed pipe, hold your breath, and concentrate on listening. The noise of a leak, unless it’s quite a large one, can be very faint and difficult or impossible to hear without mechanical assistance. Plumbing supply stores carry listening de vices that are designed to amplify the sound in pipes. These usually consist of an ice-pick-shaped pickup and an ear piece that resembles an old-fashioned telephone receiver. Just put the point of the pickup against the pipe and your ear against the ear piece. Usually the closer you are to the leak, the louder the sound tends to be— not always, but usually. So move around from place to place until the sound is loudest, and you will probably be pretty close to the leak.

Water companies are usually very cooperative in helping you find leaks. They will probably send an experienced person with a sonic leak detector to your house; such equipment can often isolate the area of the leak in a very short time. Don’t hesitate to call if you think you are wasting water and money on a hidden leak. There is usually no charge for this service.

Friday, December 9, 2011 9:31 PST