News Subscribe  to Our Newsletter Sign  up for Email Updates CGF  In the News Press  Inquiries Past  Articles Calendar			The  benefits of using reclaimed water By Larry Kolb, San  Francisco Bay Regional Water Quality Control Board Committee for Green Foothills hosted an environmental  forum in October that explored the appropriate, safe uses of treated  wastewater. Green Footnotes invited panelist Larry Kolb to describe some  of these uses for our readers. Using treated wastewater for landscape irrigation  and other uses is an old idea that is getting new interest. Wastewater  reclamation makes existing water supplies go further. For example, irrigating  local golf courses, freeway medians and cemeteries can free up freshwater  for domestic needs. In addition, because even well-treated wastewater  contains more chemicals than we can measure, direct application to soils  allows such pollutants to break down rather than polluting waterways where  it would otherwise be discharged. San Jose's  Guadalupe River Park & Gardens showcases the use of recycled  water in their Courtyard Garden on Taylor Street. For these reasons, wastewater reclamation is widely  regarded as a good thing. The State of California and its various agencies  have executive orders, resolutions, and policies endorsing water reclamation,  adopted under both political parties.  Concerns about using reclaimed water Water reclamation raises two main concerns: added cost and safety  considerations. Added costs include treatment that may be required to  meet health standards, as well as the cost of new piping to the points  of use. Safety considerations require that rigorous health-based standards  for treatment are consistently met and that use restrictions are complied  with. (An example of a use restriction is prohibiting irrigation of a  golf course during hours of use.) The hue and cry over  reclaimed water The cost and safety issues of reclaimed water can be addressed; however,  the ultimate challenge is public acceptance. Although an old saying in  the water business states that no one in California has ever gotten sick  from a reclamation project, loud public outcry surrounds many reclamation  proposals -- particularly those proposals that would inject very highly  treated effluent using reverse osmosis (similar to distillation) into  aquifers that are used for drinking water supply. The term  "toilet to tap" is a potent epithet.  Of course, we more  or less take for granted that the streams from which we take our surface  water supplies almost always have their own waste inputs. For example,  about 90 percent of the wastewater discharged into the San Joaquin River  is taken out a little further downstream and reused.  The agricultural potential for reclaimed water The really large market for reused water is in agriculture, especially  for crops like cotton or alfalfa where potential direct human exposure  is limited. If we had the political will, it would be feasible  to reclaim about half the wastewater generated in the state for agricultural  use. Since agriculture accounts for some 80% of our water use, it could  readily absorb a good part of our reclaimed water.  However, using reclaimed water for agriculture also  poses some barriers. Because farmers get freshwater supplies at huge subsidies,  many are afraid they might lose this benefit should they accept reclaimed  water. Another problem is salt. In general reclaimed water has somewhat  more salinity than river water, and its use would make the San Joaquin  Valley's already-serious salinity buildup problem slightly worse. Water reclamation brings environmental benefits,  including reduced need for new dams A new argument for agricultural use of reclaimed  water is that it could alleviate some of the impacts of climate change.  There is a very good chance that we will lose most of the free seasonal  water storage provided by snowpack as our winters get warmer, especially  at higher elevations. Instead of replacing this storage with new reservoirs,  we could shift to use of reclaimed water, which is available year-round. Today there are two trends that we can see for California  water supplies. One is more use of reclaimed water. The other is increasing  use of desalination to allow use of salty or brackish water for domestic  use. Together these technologies have the promise of meeting our needs  for additional urban water while minimizing the need for costly and environmentally  harmful new dams. Published October 2003 in Green  Footnotes . Page last updated November 13, 2003

	Photo courtesy of South Bay Water Recycling.