There is no new water.
By Frances Spivy-Weber
"Earth is a big water-recycling machine, moving water between the land, the sea, and the atmosphere. No water gets lost, it merely changes locations, quality, and form." Sandra Postel, Pillar of Sand (Worldwatch Institute, 1999)
If we can accept that there is no new water, let's add a few additional facts:
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California's (and the world's) population will rise sharply over the next few decades. The numbers are debatable, but the trend is not.
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California's economic growth during the same period will place increased demands for water, particularly high quality water, on local and regional governments.
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Water quality research is leading federal and state agencies to ratchet up water quality standards. Water treatment research, particularly membrane technology, is moving ahead quickly, too.
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Traditional water users are increasingly expected to share water with the environment--fish, recreational streams and rivers, watershed wetlands and natural areas--and to protect the environment from polluted water.
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During droughts, no area of California can count on imported water, so a local strategy for self-sufficiency is important.
There is a simple solution to the California's (and the world's) increasing demand for good quality water: improve water's productivity by using less and using what we have more. And high on the list of strategies for increasing water use efficiency is water recycling.
This article will focus on reclaiming highly treated water from sewage treatment plants and putting it back into use. There are other opportunities, too, such as capturing, treating, and re-using storm water, dry-weather run-off, agricultural drainage, and water used in industrial processes. Water productivity must also come from developing new crops, cultivation, and irrigation methods that use water more efficiently, and as we are doing now with the environment, making some hard, value-laden decisions about re-allocating the "rights" to water.
Water Recycling
The stream of water going into sewage treatment plants from homes, gardens, the street, and industries is guaranteed to increase during the first half of this century. If that water can be separated from contaminants and treated for health and safety, it is a valuable, local addition to our water supply for people and the environment. If not made safe for reuse, many more sewage treatment plants will have to be built to handle the increased volume and new schemes for disposing of the wastewater will have to be developed.
Thankfully, treatment techniques are good and getting better every day, and many communities, particularly in Southern California, have developed cost-effective ways to use recycled water that are safe and receive the Health Department's seal of approval. Experts say that some of the "cleanest" water being used today is reclaimed water for landscape and agricultural irrigation, industry, direct groundwater recharge, and injection wells as barriers to salt water intrusion into coastal groundwater basins.
The Mono Lake Committee is strongly committed to helping Los Angeles and the state of California make the best use of its available water. We know there are many questions raised about recycled water by the press and others, and following are some answers to most common ones:
Is reclaimed water safe?
Most people's questions about reclaimed water are variations on an understandable uncertainty about the health and safety of taking wastewater, treating it, and using it again in ways that may one day put that water into your tap. What are the risks? What are the safeguards?
First, let's go back to the first statement of this article: there is no new water. So, people are already drinking water that is brought in from the aqueducts or pumped from the ground that has been used by many others upstream, and much of that use is not "pretty." The way we assure ourselves that this water is safe is that we create federal and state health standards for water and before drinking water is piped to homes and businesses, it is treated to meet those standards. Reclaimed water projects, on the other hand, are reviewed and evaluated by more than a dozen federal, state, and local agencies responsible for protecting the environment, public health, and water. Reclaimed water is given high levels of treatment before it is first introduced into the environment, and there are restrictions on how it is introduced into the environment. Once introduced, reclaimed water is monitored, blended with other water underground, and months or years later, treated again, when it is pumped from the ground to be used as drinking water.
Increasingly more restrictions must be put on upstream users to greatly reduce their degradation of the water, but changing the habits of industries, towns, farmers, foresters, citizens who wash cars, water lawns, etc. will take time. Therefore, it is no exaggeration to say that reclaimed water is the cleanest water being introduced into the environment for reuse.
How does reclaimed water help stretch water supplies in a drought?
Most Californians are familiar with the reality of droughts, which limit the amount of water available to all water users--agriculture, industry, communities, the environment. When the Sierra Nevada snow pack is low, there is not much water to export to urban centers or to farms. Those communities who have local sources of water are in the best position to maintain near normal conditions for their residents. Reclaimed water is a local source. It can be used to substitute for imported or pumped groundwater. It can be used to replenish groundwater basins and to keep them filled.
Are there other benefits of using reclaimed water?
A great deal of public and local taxpayer money goes into treating
wastewater to secondary levels and then disposing it somewhere, usually
into streams, bays, or the ocean. For only a small additional cost,
this water can be treated a third time to "drinking water
quality" and used again. Some industries--oil companies,
technology companies--are eager to take this tertiary-treated water and
use it for cleaning their systems, which are highly sensitive to
"dirty" water. In Southern California, Chevron, Arco,
Mobile and others have shifted from treating regular drinking water to
using reclaimed water from El Segundo's West Basin Water Recycling
Facility, because it comes to them "cleaner" and less damaging
to their equipment.
The East Valley Water Recycling Project in Los Angeles is scheduled this year to begin delivering water to spreading grounds in Los Angeles, which will over five years filter into the City's groundwater basins. The Mono Lake Committee worked closely with state leaders in the 1980s and early 1990s to raise $36 million for this project. The reason was simple. The project will ultimately deliver 35,000 acre feet per year of recycled water--enough to supply water to 200,000 families each year--and it will help to offset the up to 78,000 acre feet of water that Los Angeles is not getting while the lake rises. The Committee helped with other conservation and water-recycling projects to meet Los Angeles' water needs, but this project is extremely important.
How much experience do water agencies have with mixing reclaimed water and groundwater?
For over forty years Los Angeles and Orange Counties have recharged their groundwater with some recycled water. Studies in 1984, 1987, and 1996 each found that the use of recycled water for groundwater recharge used for drinking water resulted in no harmful effects.
For 25 years, Orange County Water District's Water Factory 21 has successfully purified wastewater and produced highly treated drinking quality water to inject into their coastal seawater intrusion barriers, protecting the county's critical groundwater supply. The treated water eventually blends into the groundwater.
What about the cost of recycling?
Recycling is not cheap, but the cost of reclaimed water has come down over the years as utilities gain experience and as technology changes. At the same time, the cost of imported water has gone up, particularly during drought years, making the difference between the cost of recycled and imported water more negligible. When this reduced cost difference is added to the reliability of reclaimed water in a drought, the cost arguments against recycling are muted.
If these questions have raised more questions in your mind or if you just want to talk to someone about recycled water and other water policy measures, please call me (310-316-0041).
This article will appear in the Summer 2000 Mono Lake Newsletter. On Sunday May 21 in the Valley Section of the L.A. Times, an Op-ed will appear on the East Valley Water Recycling Project, written by Frances Spivy-Weber and David Freeman.
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