More than 370,000 Californians have contaminated drinking water, with people of color making up a disproportionate fraction of those affected, according to a UC Berkeley study.
The study focused on contamination from arsenic and hexavalent chromium, known carcinogens and nitrate, according to Clare Pace, study author and campus postdoctoral researcher. Pace added that nitrate can cause “blue baby syndrome,” a condition where babies lack sufficient oxygen in their blood.
Researchers examined differences in water quality between larger community water systems, which collectively serve 37 million California residents, and smaller domestic wells, which serve 1.3 million residents, often in rural areas. They found that 12.1% of domestic well users have water with an unsafe level of contamination, compared to just 0.6% of community water system users.
“This study is the first statewide environmental justice analysis of water quality in California communities served by community water systems and domestic wells,” Pace said in an email. “We found that people of color were more likely to drink water with elevated levels of these contaminants.”
According to Pace, both equity and water quality are worse in rural areas dependent on small water systems, such as the San Joaquin Valley. The San Francisco Bay Area, which largely relies on community water systems, has lower contaminant levels than the state average, she added.
While the study did not focus on the causes of water quality issues, it pointed to industrial and agricultural activity as potential sources of contaminants. Pace added that water shortages can exacerbate quality issues.
“In this era of climate change, our groundwater is becoming an increasingly precious resource, and we’re facing historic levels of drought and well failures,” Pace said in the email. “Even if a well doesn’t fail, drawdown of the water table can worsen drinking water quality by concentrating contaminants, making these problems even worse.”
Pace noted that the study could help prioritize funding and water quality testing to areas most in need. The research team behind the study also created a drinking water tool to provide localized information on the quality, quantity and management of the water supply, she added.
In 2012, California passed the Human Right to Water bill, which enshrined access to clean water as a right. Noting that the state has fallen short of this goal, Pace said information provided by the study could help achieve it.
“California is the first state to legislatively recognize the Human Right to clean drinking water,” Pace said in the email. “Going forward, the way in which these laws are implemented will make a big difference on whether equitable outcomes are actually achieved.”