WASHINGTON, DC – Republican Michigan Gov. Rick Snyder has turned down a second request to testify at Democrats' congressional hearings on the Flint water crisis. Snyder spokeswoman Anna Heaton told The Hill Monday that the governor won't be able to attend the hearings because he will make his annual budget presentation to the Legislature Wednesday. In it, he's expected to ask for $30 million to assist Flint residents pay for water they can't trust to drink.

But the full costs of the repair of public infrastructure that contributed to the public health catastrophe won't be known before Snyder presents his budget, but they could come anywhere from hundreds of millions of dollars to as high as $1.5 billion, the Detroit Free Press reported. In a letter to Snyder last week, Democrats on the caucus's Steering and Policy Committee said that "seeing how it was your administration's decision that led to this public health crisis, including Michigan's Emergency Manager Law, we believe it is important to hear testimony from you on this matter."

"The ongoing Flint water crisis is a terrible tragedy," they added. "As the governor of the state of Michigan, the families of Flint and all Americans deserve to hear testimony directly from you on how this man-made crisis happened, and what is being done at the state level to make it right." In 2014, a Snyder-appointed emergency manager approved the switch of Flint's water supply from Lake Huron to corrosive Flint River water, which caused lead in aging infrastructure to leach and expose an unknown number residents to lead poisoning. In children, lead can cause irreversible brain damage.

Top administration authorities repeatedly downplayed the severity of the problem in Flint, and reportedly said they had installed corrosion controls recommended by the U.S. Environmental Protection Agency when they hadn't. Regional EPA director Susan Hedman resigned over the crisis last month.

Snyder has spent much of 2016 deflecting public criticism about his administration's handling of the crisis.