Remarking on his meeting with Flint Mayor Karen Weaver Tuesday at the White House, Obama said "I told her that we are going to have her back". "It is a reminder of why you can't shortchange basic services that we provide to people".

Obama's pledge rolled into motion on Saturday, when the president signed an emergency declaration authorizing the Federal Emergency Management Agency (Fema) to provide bottled water, filters and testing supplies for 90 days.

But he declined to make a major disaster declaration, finding that the situation "does not meet the legal definition of a 'major disaster'".

The president also criticized MI officials who made a decision to start using the polluted Flint River as a water supply in April 2014 to save money. Focus has honed in on Snyder, who opponents claim took too long to respond when tests indicated high levels of lead in Flint's drinking water.

In addition, the White House also sent Nicole Lurie, the deputy secretary for preparedness at the Department of Health and Human Services, to coordinate federal efforts in Flint.

The president spent almost an hour at the auto show, looking at crash avoidance technology from ZF TRW and sitting in a 2017 Chevy Bolt EV, an all-electric vehicle that will be available late this year.

Hillary Clinton brought more attention the problem - and its potential political ramifications - when she declared during Sunday's presidential candidate debate that "every single American should be outraged" by the water crisis.

Experts have said applying the corrosion controls would have stopped lead connections from leaching the toxic metals into the drinking water and exposing children to them.

A group of bipartisan lawmakers including Michigan Republican Fred Upton, of the U.S. House Energy and Commerce Committee, wrote last week to EPA head Gina McCarthy, requesting a briefing about Flint. After counting loan repayments, dividends and stock sales, the federal government recovered $70.5 billion. "He saved Michigan. Where do you go from there?"

Speaking at a joint General Motors-United Auto Workers facility, Obama opened his speech decrying the water contamination calamity, which has spurred accusations of government negligence and cover-ups.

In an interview this week, Mr Snyder admitted it was a disaster but denied it was his "Katrina moment" - a reference to the much-criticised response of President George W Bush to the hurricane that devastated New Orleans in 2005. Only about 41 percent supported the aid.