News from the Silicon Valley Water Purification Center:
"For the final step, the water flows through chambers that zap it with strong ultraviolet light. Like a powerful disinfectant, the UV rays scramble the DNA (and thus neutralize) any remaining viruses and other trace organic compounds, in a process similar to the sterilization of medicine, food and fruit juices. In all, the process removes 99.99 percent of all pathogens.
The resulting purified water has a TDS (total dissolved solids) content of 40 parts per million. For comparisons sake, drinking water in the county averages 215 parts per million, while the recommended maximum contaminant limit is 500 parts per million. In other words, water from the advanced purification center is clean enough to drink, as one enthusiastic county official did at the plant’s unveiling.
For now, the water is going toward improving the quality of the county’s recycled water, used for irrigating crops and watering golf courses, parks, school lawns, street medians and business park landscaping. It’s also used to cool buildings and data centers, which will eventually include Apple’s new campus in Cupertino, opening in mid-2016. The tech giant is working closely with the water district to expand local recycled water programs, and is contributing $4.8 million toward the construction of a similar advanced recycled water facility near the coming campus.
With the potable quality of the water, the plan all along has been to introduce it into local taps by 2025. But as California’s drought continues, the project may get fast-tracked, and residents may be drinking the recycled water in as little as two years. In that scenario, the recycled water is pumped into aquifers to recharge groundwater, then pumped up, retreated and piped to local homes."