Demonstrators protest over the water crisis in Flint, Mich., on March 6. (Rebecca Cook/Reuters)

Gina McCarthy is administrator of the Environmental Protection Agency.

This week, I will testify along with Gov. Rick Snyder and others from Michigan and Flint about the health crisis in the city. This conversation is needed because what happened in Flint should not have happened.

The crisis is the result of a state-appointed emergency manager deciding that, to save money, Flint would stop purchasing treated drinking water from a source it relied on for 50 years and instead switch to an untreated source. The state of Michigan approved that decision, and it did so without requiring corrosion control. These decisions resulted in Flint residents being exposed to dangerously high levels of lead.

Under the Safe Drinking Water Act, Congress gives states primary responsibility for enforcing drinking water rules for the nation’s approximately 152,000 water systems, but the Environmental Protection Agency has oversight authority. The EPA’s relationship with states under the act is usually a strong and productive partnership. But looking back on Flint, it is clear that, from day one, Michigan did not act as a partner. The state’s interactions with us were dismissive, misleading and unresponsive. The EPA’s regional office was also provided with confusing, incomplete and incorrect information. As a result, EPA staff members were unable to understand the scope of the lead problem until more than a year after the switch to untreated water. Michigan did not act with a sense of urgency to treat the system and inform the public in ways we have come to expect from our state partners. While we were repeatedly and urgently telling the state to do so, looking back, we missed opportunities late last summer to get our concerns onto the public’s radar.

But this week’s hearings should also bring attention to this country’s much broader water infrastructure issues — especially in underserved low-income communities.

More than 40 percent of Flint residents live in poverty. While the contours of Flint’s water crisis are unique, the underlying circumstances that led to it, sadly, are not.

As a country, we have a long history of disinvestment in such communities, which the Obama administration has been working to address. We call them environmental justice communities. Not only are these populations more vulnerable to the health effects of pollution, but they also lack the tools and resources to do something about it. That’s what stacks the deck against cities such as Flint. That’s what creates an environment where a crisis such as this can happen.

Across the United States, water infrastructure is aging, antiquated and severely underfunded — particularly in low-income communities. This threatens citizens’ access to safe drinking water — an essential for every human being on Earth.

When state and city budgets get slashed, funding for environmental programs is too often the first to suffer. A 2014 study in the Journal of Environmental Health found that more than a third of local health departments across the United States had reduced or eliminated environment-specific services from the prior fiscal year for budgetary reasons.

According to the most recent EPA Drinking Water Infrastructure Needs Survey, $384 billion in improvements are needed for the nation’s drinking water infrastructure through 2030 in order for systems to continue providing safe drinking water to 300 million Americans. That does not count the investments it would take to replace all lead water-service lines in the United States.

Serious and strategic investments are needed over the next 20 years to maintain, upgrade and replace thousands of miles of service pipes and thousands of treatment plants, storage tanks and water distribution systems — all of which are vital to public health and the economy. The longer we wait, the more expensive these needs will become.

So we are on the ground supporting the city of Flint and the state of Michigan to get the water system back on track. But while the spotlight is still shining, we have an opportunity to harness the resources and attention needed to make meaningful change.

Last month, I sent a letter to every governor and every state environmental and health commissioner with responsibility for enforcing drinking water rules — urging them to work with the EPA on infrastructure investments, technology, oversight and risk assessment, as well as public engagement and education — to keep our drinking water safe nationally.

I also initiated a national reassessment of state drinking water programs, directing the EPA to meet with officials from every state drinking water program to make sure they’re addressing any high lead levels and fully enforcing the federal government’s Lead and Copper Rule as it currently exists, while the EPA looks at how to strengthen it even more.

The EPA will do its part and looks forward to continuing discussions about best practices and needed improvements with all stakeholders. We can’t make the headway required by acting alone, and the needs of underserved populations can’t be ignored. States need to step up and invest to make sure all of their citizens have access to clean drinking water.

It’s tragic that it took a disaster of this scale for this issue to get the attention it deserves. Now let’s do something about it.