SWSIWaterConservationAndEfficiencyTRTWhitePaper

• Technical Roundtable: Water Efficiency
• Title: SWSI - Water Conservation and Efficiency White Paper
• SWSI II - Doc Type: White Papers

SWSI Phase 2 Technical Roundtable
Water Conservation and Efficiency
2. Background
Water conservation and ef ficiency practices associated with both municipal and
agricultural uses can be an important tool in meeting long-term water supply needs
and are important components of water planning. To the extent that conservation
practices are reliable, and/ or permanent in nature, such practices can reduce the
overall demand f or water on a consistent basis and thereby reduce any shortfall in
supply.
Conservation measures can take the f orm of increased ef f iciencies. However, not all
water conserved through more efficient uses corresponds to an increase in overall
water supply to a water user. For example, a water user could take steps to eliminate
certain phreatophytes and thereby "salvage" additional water. That water, however,
legally becomes part of the river administration and does not necessarily accrue to the
benef it of the specif ic water user conducting the "salvage" activity, since a water user
cannot take credit f or a"salvage" activity and thereby divert more water. Salvage
water is owed to the stream to be diverted by downstream water users pursuant to
the priority system.
3. MB~I Water Conservation
M&I water conservation programs may result in improved water use efficiency. M&I
water savings occur through the modif ication of water-using fixtures (e. g., showers,
landscapes, irrigation systems, cooling towers) and behaviors (e.g., showering time,
irrigation schedules, maintenance schedules, etc.). The effects of conservation and
ef ficiency on M&I water demand are the result of both passive and active water
conservation efforts. Behavioral changes are somewhat unpredictable in their rate of
long-term success since they require changes in consumer behavior, but can be
effective means of reducing water supply needs, with little cost to the community.
Table 1 from the SWSI report summarizes five levels of water conservation developed
during SWSI. Each level shows examples of water conservation programs that a
utility or water provider might implement at the given level of conservation effort. In
addition, the table indicates an estimated percent reduction in total M&I demand that
might result from each level of conservation; and a generalized cost of the water
savings at each level. Such generalized savings and costs may vary with the program
implementation conditions of each water provider. The percent savings and
generalized costs of each level of water conservation eff ort are described in detail in
SWSI Report Appendix E(SWSI Water Demand Forecast Report).
~ DRAFT 6
S:IMEETINGSITECHNICAL ROUNDTABLEITRT MEETING - SPECIFICIWATER EFFICIENCYISWSI WATER EFFICIENCY TRT BRIEFING.DOC