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<br />Introduction
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<br />/n nature, all water
<br />undergoes the above
<br />hydrologic cycle.
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<br />1
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<br />It has been said that all the water on this planet is all
<br />the water that will ever be. From time in memoriam,
<br />water has undergone a continuous cycle of use and
<br />reuse, In the hydrologic cycle, snow and ice melt to
<br />form lakes, lake water evaporates to become clouds,
<br />the clouds condense to become rain and snow, and
<br />so on. But each of these components, be it as a solid,
<br />gas or liquid, Inevitably remain part of the water
<br />equation and are reCYCled from form to form and from
<br />use to use.
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<br />California, the most populous state in the union, also
<br />is a state where two-thirds of the population lives in
<br />a desert climate, In this arid region, the natural
<br />occurrence of water is limited and maintaining an
<br />adequate supply of water is imperative for survival.
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<br />As a result, efficient water use is critical to sustaining
<br />water availability in this continually growing stats.
<br />One method of assuring supply reliability, water
<br />recycling, is gaining attention throughout California,
<br />With water management shifting away from
<br />the construction of new dams, reservoirs and
<br />conveyance canals, the viability of water recycling
<br />as a water source has increased over the years. New
<br />water treatment technologies are now considered a
<br />realistic way of maintaining a water supply to meet
<br />demand,
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<br />Water recycling (or water reclamation) involves
<br />treating municipal wastewater to remove sediments
<br />and impurities for reuse in both potable (drinkable)
<br />and non-potable uses, For different uses of water,
<br />there are different levels of treatment. The extent of
<br />treatment - primary, secondary, tertiary or advanced
<br />- is determined by the initial quality of the water, the
<br />reuse application and state and federal laws, Potable
<br />recycled water requires the most exlensive (and
<br />expensive) treatments - treatments proven effective
<br />in other regions of the country and world including
<br />northern Virginia, Windhoek, Namibia and Orange
<br />County, California, Most uses for recycled water are
<br />for non-potable applications: landscape and crop
<br />irrigation, groundwater recharge, stream and
<br />wetlands enhancement, industrial processes.
<br />recreational lakes, fountains and decorative ponds,
<br />toilet flushing, and as a barrier to protect ground-
<br />water supplies from sea water intrusion.
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<br />Using recycled water reduces reliance on increas.
<br />ingly scarce and expensive surface water and can
<br />minimize groundwater overdraft, that is, extracting
<br />more water than is replenished, Additionally,
<br />discharges of treated water into rivers and the ocean
<br />- which can adversely impact water quality - are
<br />reduced, Recycled water also has the advantage of
<br />being a local, drought-resistant supply-a key selling
<br />point in semi-arid states like California.
<br />
<br />Many parts of the state, particularly southern and
<br />central California, import surface water from sources
<br />in other watersheds, some hundreds of miles away.
<br />In southern California, two-thirds of the region's water
<br />needs are met by water imported via three major
<br />aqueducts (the Los Angeles Aqueduct, the Colorado
<br />River Aqueduct and the State Water Project's (SWP)
<br />California Aqueduct), Fittingly, about one-half of the
<br />state's water recycling and reuse projects are in
<br />southern California.
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<br />Central and northern California communities are
<br />developing more water recycling projects, too,
<br />Population pressures and environmental require-
<br />ments, both to improve the flow of water through fish
<br />habitats and reduce wastewater discharges into
<br />fragile ecosystems, are two primary reasons for
<br />expanding water recycling, The long-term plan to
<br />improve the water supply and ecosystem in the
<br />San Francisco Bay/Sacramento-San Joaquin Delta
<br />(Bay-Delta), the hub of the state's developed water
<br />supply system, includes water reuse in its proposed
<br />water use efficiency program. The comprehensive
<br />Bay-Delta plan is being developed by state and
<br />federal public agencies, known as CALFED, along
<br />with water interest groups (see page 19),
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