Nonresidential water use in the U.S.
It is typically subcategorized under users including Commercial, Industrial, and Institutional sub-sectors, which are often jointly designated as the ICI or CII sector.
[1] In the United States, a USGS nationwide compilation of public supply withdrawals and deliveries indicates that in 2010 the total daily volume of nonresidential use was approximately 12,000 million gallons per day (mgd) and accounted for about 29 percent of public supply withdrawals (or 45 gallons per capita per day when divided by the estimated 268 million people who relied on public-supply water).
[2] This estimate is obtained by subtracting from total public supply freshwater withdrawals (41,700 mgd) the reported domestic (residential) use (23,800 mgd) and allowing for 14 percent of unaccounted for water (because of leaks, hydrant flushing, tower maintenance, and other system losses, also called non-revenue water).
[11] Typically, the total CII use in an urban area or a region is broken down by categories of commercial establishments (and types of institutions or industrial plants) based on the kinds of goods and services provided, or their function.
Also, the Energy Information Administration (EIA) identified 85 types of commercial buildings and facilities which were grouped into 16 general categories.
A “metric” (or “performance indicator”) is a unit of measure (based on a formula) that can be used to calculate the rate of water use during a given period of time (and at a given level of data aggregation).
A “benchmark” is a particular (numerical) value of a metric that denotes a specific level of performance, such as a water-use efficiency target.
[13][14] The median values are useful when placing water use in a CII establishment among its peers because the sample distributions typically have a pronounced right tail skew.
[14][17] Mean (or average) values are useful to planners who need to estimate total category use based on results from a sample of establishments.
[14] Nationwide, there are approximately 1,012 thousand office buildings with a combined floor space of 1,952 million square feet.
[22] Assuming the WUI of 88 g/ksf/d as representing average office usage in the U.S., the total country-wide use would be 1,400 mgd or close to 12 percent of CII use.
The reported proxy metrics on water use intensity in retail outlets include an estimate of 122 gallons/1000 square feet/day (g/ksf/d) in Phoenix AZ,[25] 40 g/ksf/d in Santa Fe NM,[26] and 98 g/ksf/d for one-story stores and 115 g/ksf/d for community shopping centers based on data from eight utilities in Florida and Texas.
[10] The largest uses of water in restaurants result from kitchen activities such as washing dishes, making ice, and preparing food.
[8] The proxy metrics data show WUIs in restaurants ranging from 474 to 578 g/ksf/d in selected Colorado utilities,[9] an average of 589 g/ksf/d in Austin, Texas,[28] and 670 g/ksf/d in Florida.
[11] Most schools use water for restrooms, cooling and heating, irrigation of outdoor playing fields and lawns, locker rooms, laboratories, and cafeteria kitchens.
For example, in a sample of 706 hotels in New York City, average daily water use intensity in 2011 ranged from 60 to 456 gallons per 1000 square feet (g/ksf/d), with the median use of 215 g/ksf/d.
[11] The EPA Energy Star’s Portfolio Manager that tracks water use at CII facilities found median use in hotels of 102 gallons/room/day.
[16] Other studies reported average use of 159 g/ksf/d in Austin, Texas,[28] and a median of 140 g/ksf/d in EPA's Portfolio Managers data set.
In addition, there are 147 thousand buildings with outpatient care clinics and medical offices with the total floor space of 1,780 million square feet.
[36] In addition, water is used in the cleaning and preparation of the fresh produce, meats, and fish before the products are put onto the shelves.
