Arsenic-tainted water affects low-income residents and inmates on both sides of prison walls

BERKELEY, Calif. — Did you know that even 10 years after California recognized the human right to clean water, many residents are still drinking water that contains dangerous levels of contaminants? This includes the highly toxic mineral arsenic. Unfortunately, low-income and rural communities face the greatest challenges in accessing clean drinking water — especially if they’re living near a prison.

Researchers at the University of California-Berkeley and Virginia Tech examined how incarcerated individuals in California may be affected by arsenic-contaminated water. This study analyzed 20 years of water quality data from Kern Valley State Prison and nearby Central Valley communities, such as Allensworth, McFarland, and Delano. The findings shed light on the ongoing struggle to provide clean water on both sides of prison walls.

Long-term exposure to even small amounts of arsenic in drinking water can lead to serious health issues, including various cancers. In 2001, the U.S. Environmental Protection Agency (EPA) lowered the maximum contaminant level for arsenic from 50 parts per billion (ppb) to 10 ppb. However, the study discovered instances when the arsenic levels in the water supply of all four communities exceeded the regulatory limits for months or even years.

The researchers wanted to understand how water quality data could identify potential historic exposures to contaminants among incarcerated and non-incarcerated populations who share similar groundwater sources. They found that arsenic levels above 10 ppb persisted in all four communities, even after state funding was allocated for arsenic remediation. Shockingly, some instances of exceeding the limit did not receive official violations from the California Division of Drinking Water.

“There has been a lot of work, primarily by journalists and by incarcerated people themselves, that suggests serious environmental health hazards in prisons, and yet there have been very few studies looking at these environmental health challenges,” says study first author Jenny Rempel, a graduate student in UC Berkeley’s Energy and Resources Group, in a university release. “This is one of the few studies to document ongoing structural challenges to realizing this basic human right to water on both sides of the prison walls.”

Kern Valley State Prison, which opened in 2005, was built without plans for arsenic remediation. The average arsenic levels in the prison’s water supply remained around 20 ppb until a $6 million water treatment system was installed in 2013. Despite the treatment system, occasional spikes above 20 ppb occurred between 2017 and 2019.

Empty prison cell
(Photo by RDNE Stock project on unsplash)

While residents in surrounding communities can resort to drinking bottled water or installing home filtration systems, these options are often unaffordable for low-income households. Small, low-income communities face challenges in acquiring resources to build and maintain effective water treatment facilities.

This problem extends beyond California. Rural and low-income communities across the country, including urban areas like Jackson, Mississippi, and Flint, Michigan, are disproportionately affected by water crises. Many of these communities are predominantly people of color, highlighting the underlying issues of historical disinvestment and regulatory failures.

The study found that Delano, the largest community in the study, with a population of over 50,000, rarely exceeded the 10 ppb arsenic limit since 2013. This was achieved through the construction of new wells and treatment facilities. In contrast, the smaller community of McFarland, with a population of around 12,000, occasionally exceeded the limit despite a new treatment system. Allensworth, with approximately 600 residents, still lacks a treatment facility and relies on blending water from two wells to meet the average arsenic limit.

The findings emphasize the need for ongoing support to maintain and operate water treatment facilities in low-income communities. Affordable technologies for delivering safe water on smaller scales are also necessary to ensure universal access to clean drinking water. To fulfill the promise of the human right to clean water, researchers say California must establish adequate technical assistance and innovative approaches for communities to successfully operate treatment systems in the long term. They add it’s crucial to address the water crisis and ensure equitable access to clean water for all residents, regardless of their economic status or location.

The study is published in the journal Environmental Health Perspectives.

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  1. Wow! That’s just sad & unbelievable. I hope that this major problem get fixed for all communities & prisons that it effects. Arsenic in the water at any level is too high. This needs to be fix ASAP. It should be a basic human right for people anywhere to have drinkable clean water!! SMH!! 🙄😶

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