Facing criticism for a late response, President Obama boarded Air Force One Tuesday bound for Louisiana, to survey the damage after the devastating floods that have swept through the state.

The flooding, which comes almost eleven years to the day of Hurricane Katrina, is the worst natural disaster to hit the U.S. since Hurricane Sandy four years ago.

"Thousands of people in Louisiana have lost everything they own and need our help now," said Brad Kieserman, the Red Cross' vice president of disaster services operations and logistics.

Rainfall has been sporadic, and the damage toll, around $30 million, is expected to be even greater once the rain stops and the floods dry out, state officials said.

An estimated 6.9 trillion gallons of rain hit Louisiana between August 8 and 14, which is big enough to fill more than 10.4 million Olympic-size swimming pools. One parish, Watson, recorded almost 32 inches of rain in one day, CNN reports.

Residents are now returning to their homes only to find everything damaged and soaked. Houses in some parishes are still roof high forcing thousands into emergency shelters.
 

FEMA Director Craig Fugate has been urged to “utilize all resources available to assist in the response and recovery,” the White House said.

Still, critics have been outspoken about the President's response, waiting more than a week to visit the tens of thousands affected by the floods.

“If the president can interrupt his vacation for a swanky fundraiser for fellow Democrat Hillary Clinton, as he did on Monday, then surely he can make time to show up for a catastrophe that’s displaced thousands,” The Advocate, a local newspaper, wrote in an editorial last week.

Republican presidential nominee Donald Trump, who visited Baton Rouge last Friday, was praised by Louisiana Gov. John Bel Edwards who told CBS News “it helped to shine a spotlight on Louisiana and on the dire situation that we have here.”

At least 13 people have died since the flooding began August 11.

In light of the devastation, an outpouring of support has come from across the nation.

Pop star Britney Spears, who is from Kentwood, Louisiana, tweeted out links Tuesday to a fundraising site offering $10 raffle tickets to win an outfit from her upcoming performance on Sunday's MTV Video Music Awards or win a trip to New York to see her at the show in person.

Other contributions have come from unlikely places, with SOURCEvapes offering 100 percent of all sales profits from its online store to be donated to Louisiana relief efforts from now until Labor Day.

Reverend Jesse Jackson, who just returned from Louisiana has launched a humanitarian relief drive for as part of the Rainbow PUSH Coalition and United Christian Faith Ministries.

Rainbow PUSH is accepting new and unopened bottled water, first-aid kits, feminine hygiene products, disposable diapers, baby wipes, cleaning supplies, as well as products for the elderly.

If you’d rather donate cash, both the American Red Cross and the Salvation Army are accepting monetary donations for flood victims.