11 Dead in 'Historic' Louisiana Flooding

PHOTO: David Key boats away from his flooded home after reviewing the damage in Prairieville, Louisiana, Aug. 16, 2016.PlayMax Becherer/AP Photo
WATCH Louisiana Governor Declares State of Emergency Due to Unprecedented Flooding

Eleven people have died from torrential rain and flooding in southeastern Louisiana, which Gov. John Bel Edwards today described as "unprecedented" and "historic."

About 40,000 homes have been affected by the flooding, Edwards said.

More than 20,000 people have been rescued and about 8,000 were in shelters Monday night, according to Edwards.

President Obama declared a federal emergency in the state on Sunday.

PHOTO: Ryan Evans walks along a flooded road, Aug. 15, 2016, in Baton Rouge, Louisiana.Joe Raedle/Getty Images
Ryan Evans walks along a flooded road, Aug. 15, 2016, in Baton Rouge, Louisiana.

PHOTO: A Coast Guard crew searches by helicopter for people who may need assistance in flooded areas of Baton Rouge, Louisiana, Aug. 15, 2016.Melissa Leake/AFP/Getty Images
A Coast Guard crew searches by helicopter for people who may need assistance in flooded areas of Baton Rouge, Louisiana, Aug. 15, 2016.

PHOTO:
SLIDESHOW: Louisiana Residents Clean Up After Catastrophic Flood

Livingston Parish Sheriff Jason Ard told ABC News that 80 percent of the homes in the Baton Rouge area may be destroyed from the flooding.

In 24 hours, 21 inches of rain fell in Livingston Parish, just under the 24-hour state record of 22 inches, set in 1962.

PHOTO: A boy rides his bike inside the flood damaged Life Tabernacle Church, Aug. 15, 2016, in Baton Rouge, Louisiana.Brendan Smialowski/AFP/Getty Images
A boy rides his bike inside the flood damaged Life Tabernacle Church, Aug. 15, 2016, in Baton Rouge, Louisiana.

PHOTO: A flooded home is seen, Aug. 15, 2016, in Baton Rouge, Louisiana. Joe Raedle/Getty Images
A flooded home is seen, Aug. 15, 2016, in Baton Rouge, Louisiana.