Metering Water Use
In general, meters are instrumental to a number of conservation efforts because they provide information on water use to consumers. Universal metering for conservation consists of installing water meters in existing customer sites where they do not currently have meters, and assuring new construction is metered. Installing a meter where none exists provides the customer the information needed to recognize volumetric price incentives. An associated activity is the replacement of existing meters that are not operating properly. Replacing meters that are not operating properly may “true up” the price signal sent to customers.
- BMP 4 – Metering with Commodity Rates.
- Metering is a necessary condition for implementing BMP 11 – Pricing.
Available Water Savings Estimates
Summary of Individual Studies
Speedwell (1994) analyses data from a sample of 590 multi-family buildings in New York City and a sample of 676 multi-family buildings in Jamaica, New York. The Jamaica service area was metered and the New York City buildings were not. A statistical model was developed, regressing housing density, median income in the census tract, building size water use, and a dummy variable for Jamaica service area on water use. Controlling for these independent variables, metered billing resulted in a 36 percent decrease in water use, which the authors attribute to the metering of water consumption.
Bishop and Weber (1995) report the results of a statistical analysis of Denver’s universal metering program. The average annual water savings is reported as 28 percent, with a summer peak seasonal reduction of 38.4 percent in 1991. The authors cite landscape irrigation as the reason for the large summer savings with metering. The authors report that controlling for season, weather, and the effect of metering and conservation practices, 98 percent of the monthly variation is explained in the model. However, savings estimated in the statistical model cannot be separated from savings from concurrent programs used to promote the installation of conservation devices, such as bathroom retrofits. The savings effect is also not separated from the effect of newly metered accounts that may have systematic differences in lot size, income, or housing density.
Leblanc (1997) notes that the Residential Water Metering Study in Greater Vancouver assumed that “residential water meters, an appropriate rate structure and bimonthly billing would result in a 20 percent reduction in single family residential consumption, “based on the experience in other areas.”
Lovett (1992) reports water savings from the addition of universal metering has been in the range of 25 to 40 percent where it has been implemented in several Canadian locations.
Koch and Oulton (1990) report that single family dwellings that have been converted to individual meters save on average 20 to 30 percent.
CUWCC (2003) estimates that metering with volumetric pricing reduces demand by an average of 20 percent. Water consumption in un-metered service areas is considerably higher than in metered service areas.
Maddaus (2001) found an average reduction in water use of 18 percent due to the addition of meters with “associated publicity” in Davis, California. The study also found higher percent savings for high use customers.
Brown and Caldwell (1984) compiled water savings estimates in Table 1, here reproduced from Michell (2002) who reproduced the table from the original report. The Brown and Caldwell study for the U.S. Department of Housing and Urban Development found—in its evaluation of metered and unmetered homes in Denver—that meters save 20% (Maddaus 1987).
|Table 1 Compilation of Savings Estimates|
|Study Location||Study Duration||Sample size||Water Savings %|
|Kingston, New York||1958-1963||Citywide||27.00%|
|Philadelphia, Penn||1955-1960||27% of service area||28.5-45%|
|Calgary, Alberta||1968||14,755 metered, 61,575 flat-rate||45.00%|
|Central Valley cities, California||1970||Citywide||30.00%|
|John Hopkins Study||1961-1966||Four flat-rate neighborhoods, study areas in other western cities||Little difference noted between metered and flat-rate residential in-house use; however, sprinkling use was much less for metered residences|
|Greens Thesis||1972||Three of four flat-rate areas from John Hopkins project plus surrounding metered areas||13-30%|
|Beck Report||1966-1968||Two flat-rate areas plus two metered areas from Aurora||Results similar to John Hopkins study.|
|Brysons Thesis||1971||90,290 flat-rate residential service, 19,080 metered residences||25.00%|
|Source: Reproduced from Brown and Caldwell (1984) as reported in Mitchell (2002)|
Lund (1984) compiled water savings estimates in Table 2, here reproduced from Mitchell (2002) who reproduced the table from the original report.
|Table 2 Estimates of Use Reduction from Water Metering|
|Kingston, NY||1958-63||20.00%||Cloonan, 1965|
|Boulder, CO||1960-65||40.00%||Hanke & Flack, 1968|
|various, USA||1963-65||34.00%||Howe & Linaweaver, 1967|
|Israeli apts.||-||14-34%||Darr et al., 1975|
|Malmoe, Sweden||1980||34.00%||Hjorth, 1982|
|Solomon Is.||1969-70||50.00%||Berry, 1972|
|Flyde, UK||1970-72||10.00%||Smith, 1974|
|Malvern, UK||-||20.00%||Smith, 1974|
|Malvern, UK||1970-75||6.00%||Phillips & Kershaw, 1976|
Program and Device/Activity Cost Estimates
Participant program costs may include:
- Meter installation cost, if not paid by the supplier.
Supplier program costs may include:
- Staff time to develop meter program and new rates structure
- Meter and installation costs, if the supplier pays.
Denver Water Department (1993) reports the average cost per meter setting to be $425, including purchase, installation, repair of deteriorating lines, and public education.
Bishop and Weber (1995) report costs in the range of $250 to $750 per meter for purchase and installation. The cost to install a meter in a new construction residence is cited as $175.
Leblanc (1997) reports that the cost of meter purchase and installation is $210 for indoor and $450 for outdoor. [We assume Canadian dollars, although it is not specified in the article].
Westerling and Hart (1995) develop a cost minimization model to determine the optimal period of time between meter replacements. Their sample calculations indicate a range between 7 and 14 years.
CUWCC (2003) report the costs of the installing meter retrofits vary depending on the size of the meter. For example, costs are in the range of $500-$1000 for single-family dwellings in Central Valley/per meter, and $500-$3000 for multi-family dwellings & commercial connections. There are additional costs to read the meter and bill the residential customer with a volumetric rate.
Mitchell (2002) assembled the estimates of water meter installation costs in Table 3.
Aquacraft (2004) reported cost in new construction of $125 for meter, transmitter, and installation ($300 for retrofits), $25 for receiver, computer, and software, and an annual service fee of $36.
Payments conventions may vary from supplier to supplier. For example, where new development takes place, the developer and new owners, not by the supplier, may incur metering cost. Alternatively, the supplier may incur retrofit costs.
Confidence in Estimates
Water Savings Calculation Formula(s)
S = Household_Water_Consumption * Savings_Percent
- Household_Water_Consumption is the pre-metering consumption
- Savings_Percent is the percent savings assumed to result from metering\Factors to Consider in Applying the Formula
Household water consumption may variable considerably by socioeconomic status, climate, and landscape variation.
With available information, savings can be calculated by taking a service area water use and multiplying by percentage savings. Table 4 shows sample calculations for different levels of water use.
Questions to Ask
- Are there other agencies that you can partner with to make your program more cost effective?
- Does your agency have access to grant or other partnership type funding?
- Are current un-metered connections in easements behind the residences or in front in public property? (1)
- If in easements behind residences, does your agency maintain leak histories, which would indicate the need to replace the easement mains? (1)
- Are there currently shutoff valves with spacers (for future meter installations) inside meter boxes for your un-metered connections? (1)
- If service line shutoff valves are not already in place, are the locations of your agencies service lines known where meter boxes, shut off valves and meters are to be installed? (1)
- What is the typical distance from main to meter? (1)
- Based on the meter manufacturer chosen, what is the availability and cost of remote (radio frequency) reading? (1)
- What is the cost of meters in bulk? (1)
- Would your agency install meters or use contractors? (1)
- Can your agency bill metered customers prior to completing your meter program for all customers?
- Will your agency meter all customers within the shortest cost effective period, or spread implementation over the 10 years allowed by the BMP? (1)
- Would your agency read meters on a monthly or bimonthly basis? (2)
- Does your agency currently have a metered billing system, or would such a system have to be designed and/or purchased? (2)
- Is the water bill designed to communicate water consumption and compare like months or periods for current and past years? (2)
- What is the age of the housing stock (opportunity for leak detection)?
- How often is meter accuracy checked?
- 1. Your metering cost will vary substantially based on the responses you obtain for these questions. Hint - your operations department should be able to provide this information or direct you to those within your agency who can.
- 2. Your operational cost will vary depending on your responses to these questions. Hint - your accounting and/or your information systems department(s) should be able to provide you with these responses.
American Water and Energy Savers, “Water Submetering for Commercial Property,” URL: www.americanwater.com, April 2003.
American Water Works Association, “Water Meters: Selection, Installation, Testing, and Maintenance, 4th Edition, (M6),” 1999.
Aquacraft, Inc, et al., “National Multiple Family Submetering and Allocation Program Study” with East Bay Municipal Utility District, 2004.
Berry, N.S.M. (1972), “The Effect of Metering on Water Consumption in Honiara-British Solomon Islands,” Journal, of the Institution of Water Engineers, Vol. 26, No. 7 (October), pp. 375-380
Bishop, W. J., and J.A. Weber (1995), “Impacts of Metering: A Case Study at Denver Water,” prepared for the 20th Congress IWSA, Durban, South Africa, September.
Brown & Caldwell (1984), “Effect of Water Meters on Water Use,” Prepared for U.S. Department of Housing and Urban Development, Contract H-5230.
California Urban Water Conservation Council, “AB 514 (Kehoe): Water Meters – Support, Hearing: Senate Agriculture and Water Resources – July 1, 2003.” Letter from Mary Ann Dickinson to Senator Michael Machado, June 24, 2003.
City of Kamloops (2001), “Water Use Efficiency Committee Final Report, Appendix E.”
City of Portland Bureau of Water Works, “Multi-Family Housing Water Conservation Manual: A Practical Guide to Saving Water and Money,” undated.
Cloonan, E.T. (1965), “Meters Save Water, “ in Modern water Rates, Battenheim Publishing Co., N.Y.
Darr, Peretz, Stephen L. Feldman, and Charles S. Kamen (1975), “Socioeconomic Factors Affecting Domestic Water Demand in Israel,” Water Resources Research, Vo. 11, No. 6, pp. 805.
Denver Water Department (1993), "Final Report: Universal Metering Project, “Customer Services Section, Public Affairs Division, March.
Goodman, J. (1999), “Water Conservation From User Charges in Multifamily Rental Housing,” National Multi Housing Council, June 1999.
Goodman, J. and E. Lee (1999), “Multifamily Housing: Direct Billing Spurs Water Conservation,” National Multi Housing Council, September 1999, URL: www.nreionline.com.
Griffin, W., “Utility Billing Programs Can Lower Housing Costs,” National Submetering & Utility Allocation Association Forum, June 2001, URL: www.nsuaa.org. Hanke, Steve H. and Ernest Flack Jr. (1968), “Effects of Metering Urban Water,” Journal of the American Water Works Association, Vol. 60.
Hjorth, Peder (1982), Identifying och Analys av Faktorer Vilka Styr Vattenforbrukningen och Dess Variationer, Report No. 3068, Department of Water Resources Engineering, Lund Institute of Technology, University of Lund, Lund, Sweden, 47. pp.
Howe, Charles W. and F.P. Linaweaver Jr. (1965), “The Impact of Price on Residential Water Demand and Its Relation to System Design, “Water Resources Research, Vol. 1.
Industrial Economics, Inc., “Submetering, RUBS, and Water Conservation,” for National Apartment Association and National Multi Housing Council, June 1999.
Koch, R. N. and R.F. Oulton (1990), “Submetering: Conservation’s Unexplored Potential,” AWWA Conference Proceedings
Koch, T., “Water And Heat Savings In Russian Apartment Buildings - Results Of The Dubna Project,” Institute for Energy Policy, Undated.
Las Vegas Valley Water District, “The Impacts of Submetering on Water Usage at Two Mobile Home Communities in Las Vegas, Nevada,” with Aquacraft Inc., Proceedings of the American Water Works Association Water Sources Conference, 2002.
Leblanc, L., et al. (1997), “Is Residential Metering Cost-Beneficial in Water-Rich Greater Vancouver?” Conference Proceedings of the American Water Works Association, Pacific Northwest Section
Lovett, D. (1992), “Water Conservation Through Universal Metering,” 44th Annual Convention of the Western Canada Water and Wastewater Association Proceedings.
Lund, J. R. (1986) “Metering Utility Services: Theory and Water Supply Applications,” Water Resources Series Technical Report No. 103, University of Washington, Dept. of Civil Engineering.
Maddaus, L.A., “Effects Of Metering On Residential Water Demand for Davis California,” Master’s Degree Project for the Civil & Environmental Engineering Department, University Of California, Davis, March 2001.
Maddaus, W.O., “The Effectiveness of Residential Water Conservation Measures,” Journal AWWA, March 1987.
Mitchell, D.M., “Cost of Meter Installation for Different Areas of CA,” Memo to Eric Poncelet, CONCUR, Inc., December 13, 2002.
Mitchell, D.M., “Water Conservation Benefits Of Metering/Volumetric Billing,” Memo to Eric Poncelet, CONCUR, Inc., October 21, 2002.
National Submetering & Utility Allocation Association, “Bibliography Of Utility Submetering and Allocation Industry Information,” URL: www.nsuaa.org, undated, downloaded August 2004.
Phillips, J.H. and C.G. Kershaw (1976), “Domestic Metering - An Engineering and Economic Appraisal,” Journal of the Institution of Water Engineers and Scientists, Vol. 30, No. 4, pp. 203-216.
Rosales, J., C. Weiss, and W. DeOreo, “The Impacts of Submetering on Water Usage at Two Mobile Home Communities in Las Vegas, Nevada,” 2002 Water Sources Conference Proceedings.
Seattle Public Utilities, “Sub-Metering: The Next Big Conservation Frontier?” presented at Conserv99, 1999.
Smith, R.J. (1974), “Some Comments on Domestic Metering,” Journal of the Institution of Water Engineers, Vol. 28, No. 1, pp. 47-53.
Speedwell, Inc. (1994), “The Impact of Metered Billing for Water and Sewer on Multifamily Housing in New York,” prepared for the New York City Department of Environmental Protection and the New York City Rent Guidelines Board, September.
Water Resources Engineering Inc., “Overview of Retrofit Strategies: A Guide for Apartment Owners and Managers,” for U.S. Department of Housing and Urban Development, May 2002.
Water Resources Engineering Inc., “Retrofitting Apartment Buildings to Conserve Water,” for U.S. Department of Housing and Urban Development, May 2002.
Westerling, D.L., and F.L. Hart (1995), “A Rational Approach for Making Decisions on Replacement of Domestic Water Meters,” Journal NEWWA, December.
- Metering can also be used to separately measure indoor from outdoor use. In this document, we refer to these meters as “dedicated [landscape] meters” and this topic is covered in the section on Large Landscape Measures.