Page 18 - WaterSense at Work

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October 2012
1.2
Water Management Planning
Establishing aWater Use Baseline
Establishing a water use baseline provides a reference point from which progress
can be measured toward achieving water management goals. It is also an important
component of developing a facility water balance, as discussed below. To develop a
water use baseline, consider the following:
••
Using the water bills gathered from one or two years prior, document the facil-
ity’s water use history using a form such as the Water Consumption History Work-
sheet provided in Appendix B. In addition, consider documenting and tracking
water use history using ENERGY STAR’s Portfolio Manager.
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••
Calculate the facility’s total annual water use for each metered and unmetered
water source and total for all water sources combined. This total annual water
figure will serve as the facility’s water use baseline.
••
If long-term historical water use data are available, look for any anomalies that
might suggest that the established water use baseline is not representative of
typical facility water use (e.g., a large leak or a system or process change that
occurred and temporarily skewed water use). If an anomaly is present, either
adjust the baseline as appropriate or identify a different year that can serve as
the baseline.
Inventorying Major Water-Using Fixtures, Equipment, Systems, and Processes
Once the baseline is established, it is critical to understand how specific fixtures,
equipment, systems, and processes contribute to the overall facility water use. This
process can help the water management team establish a baseline for individual end
uses of water and identify potential reduction opportunities. It can also facilitate the
establishment of water management planning goals. Three important components
of a water assessment include: reviewing existing data, touring the facility to inven-
tory water-using equipment, and verifying water use when possible.
Reviewing Existing Data
As a first step in the inventory process, plot one or two years of water use data from
bills, log books, or other available sources to identify seasonal trends or abnormal-
ities. Note any peaks, particularly in the summer months, which can indicate how
much additional water is used for building cooling and irrigation systems. Use this
analysis to estimate cooling and irrigation water use, if those sources are not subme-
tered.
Touring the Facility to Inventory Water-Using Equipment and Meter Locations
Touring the facility to identify and inventory all of the major water-using fix-
tures, equipment, systems, and processes is a key step in identifying how a facil-
ity can improve its water efficiency. During the tour, note any obvious areas for
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Ibid.