The drinking water disaster unfolding in Flint, Mich., is a powerful reminder that strong environmental regulations are often vital public health safeguards as well. That’s why a presidential veto announced early Wednesday is worth commending.

In only his ninth veto in office, President Obama stopped Congress from dealing a death blow to the proposed protections for small, upstream waterways that ultimately lead to drinking water sources for an estimated 117 million Americans.

The new protections are known as the U.S. Environmental Protection Agency’s “Clean Water Rule.” The long-simmering debate over the measure has bordered on hysteria at times. Opponents — mainly corporate agriculture, property-rights purists and conspiracy theorists — have inaccurately portrayed the protections as something new and sinister that will leave bureaucrats standing guard over puddles.

The reality is that the rule re-establishes long-standing protections that were in place for years under the nation’s Clean Water Act. That enlightened law was passed in 1972 as the public demanded action to clean up the heavily polluted Great Lakes and rivers so filled with waste that they started on fire.

But in 2001 and 2006, U.S. Supreme Court rulings raised questions about the law’s jurisdiction over wetlands or streams connected with bigger waterways relied on for drinking water. The Clean Water Rule just clarifies that the law does have jurisdiction, reinstating protections in place for decades without causing the regulatory hell opponents warn of.

Regrettably, Congress put political considerations ahead of public health recently, passing with bipartisan support a measure aiming to not only block the rule but also to prevent future protections. Leading the charge to kill the rule: Iowa’s junior senator, Republican Joni Ernst.

The congressional action looks especially wrongheaded as Flint’s misery unfolds. The community’s drinking supply — water from a polluted local river that corroded lead pipes — is poisoning residents. Opponents to the Clean Water Rule have been quiet about Flint, but in an election year, we will hear the rule derided again as a bureaucratic overreach or a federal takeover. This time, Ernst and others should be asked to back up their antiregulatory rhetoric by publicly downing a nice, big glass of Flint tap water.