Aerial views of flooding in Texas

Baseball fields sit in floodwaters in Lumberton, Texas, on Aug. 31, 2017.

Three boys take a seat as floodwaters rise around damaged railroad tracks near Lumberton, Texas, on Aug. 31, 2017.

Rising floodwaters cause damage to a home near Lumberton, Texas, on Aug. 31, 2017.

A drop-off point for boat rescues in Lumberton, Texas, on Aug. 31, 2017.

Rising floodwater with an oil slick engulfs homes near Lumberton, Texas, on Aug. 31, 2017.

California Air National Guard Master Sgt. Adam Vanhaaster searches flooded residential neighborhoods near Lumberton, Texas, on Aug. 31, 2017.

A military search and rescue helicopter refuels midflight before resuming night missions over areas flooded by Hurricane Harvey near Lumberton, Texas, on Aug. 31, 2017.

Rising floodwater engulfs an entire residential neighborhood in the aftermath of Hurricane Harvey near Lumberton, Texas, on Aug. 31, 2017.

Rising floodwater engulfs an entire residential neighborhood in the aftermath of Hurricane Harvey near Lumberton, Texas, on Aug. 31, 2017.

Coca-Cola delivery trucks sit idle in floodwater in Lumberton, Texas, on Aug. 31, 2017.

Cattle wander the flooded streets of Lumberton, Texas, on Aug. 31, 2017.

A cow sits in a pasture surrounded by floodwater left in the wake of Hurricane Harvey on Aug. 31, 2017, near Orange, Texas.  (Scott Olson / Getty Images)

Rising floodwater engulfs an entire residential neighborhood in the aftermath of Hurricane Harvey near Lumberton, Texas, on Aug. 31, 2017.

Rising floodwater engulfs an entire residential neighborhood in the aftermath of Hurricane Harvey near Lumberton, Texas, on Aug. 31, 2017.

Rising floodwater engulfs an entire residential neighborhood in the aftermath of Hurricane Harvey near Lumberton, Texas, on Aug. 31, 2017.

People launch boats from a highway overpass into floodwaters in the aftermath of Hurricane Harvey in Kountze, Texas, on Aug. 31, 2017.

A boat floats near homes flooded by Hurricane Harvey in Beaumont, Texas, on Aug. 31, 2017.

Floodwaters surround homes in Orange, Texas, on Aug. 31, 2017.

Flooding from Hurricane Harvey rushes over a road in Beaumont, Texas, on Aug. 31, 2017.

Flooding from Hurricane Harvey covers roads in Beaumont, Texas, on Aug. 31, 2017.

Trucks drive through flooded streets in Orange, Texas, on Aug. 31, 2017.

Construction materials float along the mostly flooded Interstate 10 in Vidor, Texas, on Aug. 31, 2017.

Floodwaters surround homes and businesses in Port Arthur, Texas, on Aug. 31, 2017.

Floodwaters surround homes in Port Arthur, Texas, on Aug. 31, 2017.

Petroleum spill-off flows through floodwaters in the aftermath of Hurricane Harvey in Beaumont, Texas, on Aug. 31, 2017.

High water levels at the Addicks Reservoir in Houston on Aug. 29, 2017.

Lake Houston’s spillway in Houston on Aug. 29, 2017.

Residential neighborhoods near Interstate 10 sit in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

Residential neighborhoods near Interstate 10 sit in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

Residential neighborhoods near Interstate 10 sit in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

Residential neighborhoods sit in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

Residential neighborhoods near Interstate 10 sit in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

Residential neighborhoods near Interstate 10 sit in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

Recreational vehicles lay on their sides in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

A house is nearly submerged in floodwater in the wake of Hurricane Harvey in Houston on Aug. 29, 2017.

People walk through flooded neighborhoods after Hurricane Harvey in Houston on Aug. 29, 2017.

People come out to visit the flooded areas near their homes in Houston on Aug. 29, 2017.

Interstate 10 remains flooded after Hurricane Harvey in Houston on Aug. 29, 2017.

Vehicles sit on interstate 10 in Houston on Aug. 29, 2017.

Downtown Houston on Aug. 29, 2017.

Hurricane Harvey’s storm clouds move east, revealing clearer skies, in Houston on Aug. 29, 2017.