The new regulations would ramp up restrictions on pathogens, calling for scrubbing away more than 99.9999% of diarrhea-causing viruses and certain parasites. Also a series of treatments are designed to break down chemical contaminants like anti-seizure drugs, pain relievers, antidepressants and other pharmaceuticals.so they are found in low concentrations in recycled sewage and groundwater.
The new rules call for extensive monitoring to ensure the treatment is working. Some harmful chemicals, such as lead and nitrates, which are dangerous to babies and young children, will be tested for weekly; others, monthly. And water providers must also monitor the sewage itself before it even reaches treatment for any chemical spikes that could indicate illegal dumping or spills.
Given the vast and changing cocktail of chemicals constantly in use, “we don’t know what we don’t know,” Gersberg said. “If this becomes huge in California, and it will, I believe … we should at least spend a little money.” All this treatment and monitoring is likely to be pricey, which is why Polhemus expects to see it largely limited to large urban areas that produce a lot of wastewater, such as Los Angeles County.
It would “require adding more treatment processes and increasing operating expenses,” board president Cathy Green said in a statement. “Local water agencies are currently well-equipped to continue to supply drinking water to customers in our service area at a low cost using the Orange County Groundwater Basin.”
The Santa Clara water agency, known as Valley Water, is planning a $1.2 billion project in Palo Alto to produce about 10 million gallons a day of water for groundwater recharge, but Struve said she hopes the plant also will be used for direct potable reuse in the future.