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SALINITY Recycled water generally contains more salt than traditional sources of water supply. Every time water is used for domestic, residential, commercial or industrial purposes, salinity increases. Reuse of treated water with a salt content higher than a comparable potable water supply can be problem- atic when applied to salt-sensitive crops and land- scape, recharged into underlying groundwater or used by industry. The yields of certain salt-sensitive crops can drop significantly when they are irrigated with more saline water. Percolation of recycled water with high salt contents also can increase salt levels in aquifers and high salt levels can be problematic for industry because of its corrosive properties. Recycled water in northern California generally has a lower salt content than potable water supplies in southern California. Groundwater and Colorado River supplies in the southern part of the state are quite saline. The Colorado River, which flows through seven Western states, carries an estimated 9 million tons of salt annually. The number of times water can be recycled is delermined by the salt content of both source water and urban discharge. When salt contributions are low, water may be recycled a few times before being disposed to the ocean or inland waterway. However, if the salt content is high it may be unsuitable for recycling unless it undergoes an expensive deminer- alization process (similar to the techniques used to recycle water to a potable level). Salt levels in recycled water can be reduced if industrial discharges are connected to regional brine pipelines to isolate the salts and salt levels in sewage affluent are reduced. Salt levels in wastewater also are increased by certain types of water softeners. Softeners remove calcium and magnesium from "hard water." Not all water softeners are problematic, but customer self- regenerated water softeners are a concern. These solteners require that the resident add salt (about 50-pounds a month) to "regenerate" the ability to soften hard water, resulting in a highly saline solution discharged into the sewer system. Several local districts responsible for water recycling and groundwater protection have enacted ordi. nances limiting the use of self-regenerating, sodium- based solteners. Santa Barbara County, the city of Santa Maria and the city of Escondida enacted ordinances severely restricting or banning the use of certain water softeners to stop excess discharge of salls into the wastewater collection system. The ordinances, however, were invalidated by separate appellate court decisions in 1996 and 1997 on grounds they conflicted with the state Health and Safety Code that regulates water solteners (HSC section 116775). There is increasing momentum to have the Legislature resolve the issue of increased discharges of salts by water solteners. Water supply and recycling agencies also are trying to encourage the public to choose water sotteners that are regen- erated oH site or use non-chemical water condition- ing devices. ~..-tg~}tl~:;cf~~~f.i' , .--~,*),~;- .. /f rec)'cled water is too saline. it can affeclthe yields of some salt-sensith'e crops. 11