When it comes to access to safe potable water, “race is still the strongest determinant," according to a recent report that found that more than 2 million people in the U.S. and Puerto Rico don't have access to running water and basic indoor plumbing.

The human rights nonprofit Dig Deep alongside the U.S. Water Alliance, a nonprofit dedicated to promoting investment in water infrastructure, released the new estimate in a report this month, "Closing the Water Access Gap in The United States."

George McGraw, who co-wrote the report and is the chief executive of Dig Deep, deemed the lack of water access a "silent crisis," especially in minority communities.

In Cochran, Texas, an isolated colonia in El Paso County, families haul water by car or on foot, and purchase trucked water at a cost of up to $250 per month. Brittany Anzel App / US Water Alliance

Latino and African American households are twice as likely as white households to lack indoor plumbing while Native Americans are 19 times more likely, according to the report.

Whereas communities grappling with water issues may feel like their problems are specific and isolated, the report urges looking at the issue as a national crisis and tackling it through a combination of factors: not just more government funding but encouraging partnerships with groups and flexible funding methods to provide families with the necessary infrastructure at the household level.

A history of unequal access

In areas along the Texas border as well as in rural areas in Puerto Rico, the lack of safe water and indoor plumbing goes back generations to communities that were built informally in remote areas away from the infrastructure grid. In some of the Texas "colonias," as they are called, some of the low-income families thought they would eventually get water when they built on their plots.

Brittany Anzel App / US Water Alliance

A century ago, the U.S. government responded swiftly to public health concerns by investing in water systems that provided safe drinking and wastewater services to Americans, after waterborne illnesses such as cholera were among the nation's leading causes of death.

"But when we said everybody, we meant white folks," said McGraw, adding that many poor, tribal and immigrant communities were excluded from water access initiatives.

There are currently multiple reasons as to why different communities still don't have water access. Apart from limited federal and local government budgets, most residents in these areas are too poor to pay into updating systems. Complicated regulations and permits as well as distrust between residents and government agencies have also contributed to the crisis.

Widespread unsafe water is a "ticking time bomb in terms of public health," especially when residents use springs and streams as main water sources, according to Josefa Torres-Olivo, director of the nonprofit RCAP Solutions in Puerto Rico, which works with communities on water issues.

The largest utility, Puerto Rico Aqueduct and Sewer Authority (PRASA), provides drinking water to 97 percent of the population and wastewater services to about half the island's population. Brittany Anzel App / US Water Alliance

Roughly 600 families in Guayabota, a community in the town of Yabucoa, live disconnected from the island's main water system. Many of them pipe wastewater directly into streams or use septic tanks and systems because they live far from a sewer line.

High bacteria rates in Puerto Rico’s surface water suggest that wastewater issues are widespread, according to the report. Residents told researchers that wastewater regularly floods the streets of their neighborhoods and that the situation has worsen after recent hurricanes and heavy rains.

Torres-Olivo said groups like hers aim to form collaborations between community members and the appropriate government agencies to promote local initiatives and empower neighborhoods to take the lead in developing safer water infrastructures.

Residents of other colonias use unmonitored private wells that have unpredictable water quality and availability. Brittany Anzel App / US Water Alliance

In the colonias along the Texas-Mexico border, many residents use unsupervised private wells that have unpredictable water quality and availability.

In the colonia town of Cochran, families purchase trucked water for about $250 a month for bathing or cleansing — not for drinking — or haul water by car or foot. Households in this colonia use 50 to 100 gallons of potable water a month; by comparison, the average American uses 88 gallons daily.

Unsafe drinking water and inadequate access to water sanitation contribute to about 88 percent of deaths from diarrheal diseases, according to the Centers for Disease Control and Prevention.

Climate, agriculture worsens conditions

The situation is worsening in neighborhoods with poorly constructed septic systems or sewers when extreme weather events such as hurricanes, droughts and extreme rainfall cause the sewer systems to constantly back up and overflow.

This causes the water supply to be polluted by wastewater and other contaminants.

A decade ago, tap water began to burn people's eyes when they showered and leave white residue when they washed their cars. East Orosi, California's well is contaminated by runoff from orchards surrounding the town, and from leaking septic systems. Brittany Anzel App / US Water Alliance

As climate conditions fuel more changes in rainfall, for example, this kind of water pollution will become more common, McGraw said.

Even though some rural areas counter with small drinking water systems that treat contamination with chlorination, low-income communities can struggle to afford treatment and testing.

Another issue involves the effects of agricultural and industrial production. Since 2013, thousands of Californians in the Central Valley are unable to drink water from domestic wells and municipal systems because they are contaminated with nitrates and bacteria from farm and dairy runoff, as well as arsenic, uranium and other harmful industrial chemicals, researchers found.

In 2013, thousands of people in California lost running water as a severe drought took domestic wells and municipal systems offline. The water is back on now, but many residents in the Central Valley still cannot drink it because their wells are contaminated with nitrates and bacteria from farm and dairy runoff, arsenic, uranium, industrial chemicals like hexavalent chromium, or pesticide ingredients like 1,2,3-Trichloropropane. Brittany Anzel App / US Water Alliance

In Seville, California, a primarily low-income town, a resident told researchers that she pays $60 a month for "water that is yellow and full of debris." She also spends an additional $100 a month to buy clean, bottled water, preventing her from affording other needs.

"That impacts their ability to stay healthy, go to school, work and keep a normal life," McGraw said.

These conditions across the U.S. and Puerto Rico are taking place as federal spending on water systems has declined drastically.

In 1977, 63 percent of total capital spending for water and wastewater systems came from federal agencies, according to the report. That number is now less than 10 percent, according to the Congressional Budget Office.

State and local governments have picked up some of the slack in recent years by investing in water supply systems through tax-exempt bonds, state banks, tax credit bonds and direct federal credit programs. Even so, "the federal government provides relatively little financial support to states and localities" to invest in systems that contain water such as dams, levees, reservoirs and wells, according to the Congressional Budget Office.

Despite the high costs, interview subjects stated that they only use trucked water for bathing and cleaning because they do not know whether it is safe to drink. Brittany Anzel App / US Water Alliance

Over the last few months, the Trump administration has rolled back at least two clean water regulations that helped limit the amount of polluting chemicals that could be used near water streams and regulated coal ash disposal procedures near bodies of water.

Trump’s clean water rollbacks came months after Environmental Protection Agency Administrator Andrew Wheeler cited unsafe water as the most important public health threat while minimizing the threat of climate change. Environmental groups and scientists said they are interconnected.

McGraw worries that If proper investments and coordinated efforts are not made, more people could lose reasonable access to clean water in the next decade.

Activists and groups working on water access say that providing these essential services is beneficial across the board.

"Quality of life is directly correlated with water access: Economic development and public health effects are all connected," Torres-Olivo said.

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