national multiple family submetering and allocation billing program ...

postcard survey. Nevertheless, examining indoor water use alone in these properties was deemed
important as well, since this enlarges the sample of impacted properties.
For the manager survey respondents, the first group examined were those that indicated
that they have a separate irrigation meter. Using this information and utility database codes,
irrigation-only accounts were identified for these properties and the seasonal use component was
separated out by excluding irrigation only water from the indoor totals.
For all of the remaining properties, a methodology was developed to estimate seasonal
use. Although the methods varied slightly, they were all based on the established method of
average winter consumption (AWC). In the AWC method it is assumed that there is little to no
seasonal use in the winter months of December, January, and February (or other non-irrigation
months depending on the region and climate). The average monthly indoor water use for each
property was calculated by taking the average of these three months. Multiplying the average
winter monthly consumption by 12 gives as estimate of annual total indoor use. Outdoor use can
be found by subtracting the annual indoor use from the total use.
Q12 + Q1
+ Q2
Q w
= Equation 3.1
3
where,
Q w = Average winter monthly water consumption,
Q i = Monthly water use, i = 12 (December), i = 1 (January), etc.
Q * 12 =
Equation 3.2
w
Q indoors
where,
Q w = Average winter monthly consumption
Q indoors = Total annual indoor water use
The exact method of seasonal separation for any manager survey respondents that did not
have a separate irrigation meter varied slightly depending on whether or not the property
indicated that it had an outdoor sprinkler system. It was discovered through the course of the
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