When the top official overseeing the Environmental Protection Agency's WaterSense program first heard President Donald Trump's rant about toilets that must be flushed a dozen times and modern faucets that provide only drips of water, she was at a loss for words.

"I can't even," Veronica Blette, the chief of WaterSense in the EPA's Office of Wastewater Management, emailed a handful of colleagues on Dec. 6, attaching a video of the president's remarks. Sending another tweet highlighting Trump's comments to co-workers, Blette wrote: "Sigh."

The emails were provided to NBC News in response to a Freedom of Information Act request. The emails showed part of the agency's response to what were eye-opening remarks from the president — ones he would revisit at future campaign rallies — in which he railed against the federal regulations governing toilets, showers, sinks and dishwashers.

Speaking to reporters at the White House in early December, Trump said the EPA would be "looking very strongly at sinks and showers and other elements of bathrooms" at his direction, insisting that "people are flushing toilets 10 times, 15 times, as opposed to once," and that "they end up using more water."

Last month, Trump told rallygoers in Milwaukee: "Toilets and showers. You do not get any water."

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"They put restrictions on them, and now they are permanent. Try going and buying a new faucet. Turn it on and no water comes out," he said, adding: "I have this beautiful head of hair. I need a lot of water. You go into the shower and ... drip. Drip."

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Beth Livingston, the WaterSense brand manager, had a different take, as the internal messages showed. She was responding to a faucet company executive who suggested "[you] have your work cut out for you convincing No. 45 [Trump] on your program."

"Nothing like a challenge!" Livingston, who hoped to initiate a consumer satisfaction and product performance survey regarding the WaterSense-approved products, responded Dec. 9. "We don't like faucets that only put one drop of water on my hands — LOL — the only ones I think of that might actually just drip are for Barbie doll play houses!"

In December, EPA spokesman Michael Abboud said the agency was working across other federal agencies to "ensure American consumers have more choice when purchasing water products." The EPA pointed to that comment when reached for this story Thursday.

Trump's remarks echo longstanding concern in some conservative circles about the regulations — complaints that leading environmentalists say are bunk — which they have protested against for the better part of 20 years.

The battle centers on a series of regulations and energy standards starting with the 1992 Energy Policy Act signed by President George H.W. Bush. The law set new limits on how much water a toilet can use and, in 1994, kicked into effect a standard that said new toilets, showerheads and faucets had to have water-saving designs. Since then, the federal government has regulated water flow of faucets and showerheads.

Legislation signed in 2018 mandates that the EPA review water regulations adopted before 2012, which includes the WaterSense program, which was launched in 2006. WaterSense provides an optional standard that uses less water than the mandated requirement under the Energy Policy Act.

WaterSense-approved toilets, according to the EPA's website, use about 20 percent less water than the current federal standard, With those products, "the average family can reduce water used for toilets" by 20 percent to 60 percent annually, according to the EPA website, adding that the water savings may lead to a reduction of more than $140 annually in a household's water costs.

WaterSense-approved showerheads lead to about 2,700 fewer gallons per year used by a family, per the EPA. For faucets, WaterSense says its approved products "can reduce a sink's water flow by 30 percent or more" and "can save the average family 700 gallons of water per year, equal to the amount of water needed to take 45 showers," the EPA says.

Libertarian-minded conservatives contend that the products lead people to take longer showers or to flush toilets additional times, curtailing the savings and the environmental impact.