This combination of satellite images provided by DigitalGlobe shows Simonton, Texas, west of Houston, on Nov. 20, 2016, left, and on Wednesday.
Floodwaters from Tropical Storm Harvey surround homes in Port Arthur, Texas, on Thursday.
Sharon Anderson, left, pays for gas at a Walmart in Tyler, Texas, on Thursday. It’s getting harder to fill gas tanks in parts of Texas where some stations are out of fuel and pump costs are spiking in the aftermath of Harvey.
Mike Cossey, of Bureau Veritas, uses an air monitor to check the quality of air at a police roadblock marking the 1.5-mile perimeter of the evacuation area around the Arkema Inc. chemical plant Thursday in Crosby, Texas. The Houston-area chemical plant that lost power after Harvey engulfed the area in extensive floods was rocked by multiple explosions early Thursday, the plant's operator said.
This still image taken from video provided by the U.S. Navy shows sailors from Helicopter Sea Combat Squadron (HSC) 28 rescuing 14 people and four dogs, at Pine Forrest Elementary School, in Vidor, Texas on Thursday.
Flooding from Tropical Storm Harvey rushes over a road in Beaumont, Texas, on Thursday.
Aircrewman 2nd Class Jansen Schamp, right, speaks with Harvey evacuees while rescuing them from a shelter in Vidor, Texas.
People launch boats from an overpass into floodwaters in the aftermath of Hurricane Harvey in Kountze, Texas, on Thursday.
Floodwaters from Tropical Storm Harvey surround homes in Port Arthur, Texas, on Thursday.
This combination of satellite images provided by DigitalGlobe shows Simonton, Texas, west of Houston, on Nov. 20, 2016, left, and on Wednesday, after Harvey inundated the area.
Firefighters gather during a door-to-door survey of a neighborhood that was hit by floodwaters from Harvey in Houston on Thursday. The first responders are checking homes for any emergency needs of residents as the cleanup commences after the historic storm.
Louis Naro waits with his family for a visit from Vice President Mike Pence on Thursday in Rockport, Texas, an area that received heavy damage from Hurricane Harvey.
A resident reaches out to Vice President Mike Pence during a visit to areas affected by Hurricane Harvey on Thursday in Rockport, Texas.
A boat floats near flooded homes Thursday in Beaumont, Texas, in the aftermath of Tropical Storm Harvey.
Georgi Guillory rests on the floor of an emergency shelter at a bowling alley in Port Arthur, Texas, on Thursday with her daughter, Khloe Connor, left, 6, and son Jahmaal Connor, 7, after her home was flooded by Hurricane Harvey. Cynthia Armstrong, left, also was evacuated from her flooded home.
People evacuate a neighborhood inundated after water was released from nearby Addicks Reservoir when it reached capacity due to Tropical Storm Harvey on Wednesday in Houston.
This combination of satellite images provided by DigitalGlobe shows Holiday Lakes, Texas, south of Houston, on April 3, left, and on Aug. 30, five days after Hurricane Harvey made landfall and brought historic rainfall.
Tammy Dominguez, left, and her husband, Christopher Dominguez, sleep on cots at the George R. Brown Convention Center where nearly 10,000 people are taking shelter in Houston. They have been at the shelter since evacuating Houston's Northside on Sunday.
Copano Cove in Rockport, Texas, is littered with debris on Wednesday, more than four days after Harvey roared through as a Category 4 hurricane.
U.S. Border Patrol Agent Steven Blackburn, left, checks if people wading in water need help during a search a rescue operation in a neighborhood inundated by floodwaters from Tropical Storm Harvey in Houston Wednesday.
Barbara Coleman feeds 10-month-old Landon Davis, a family friend who shares her home, at an emergency shelter at the Beaumont Civic Center in Beaumont, Texas, on Wednesday. Their home in Port Arthur was flooded Wednesday morning.
Steven Hathaway searches for people to help in an apartment complex as floodwaters from Tropical Storm Harvey rise in Kingwood, Texas.
Volunteer Elizabeth Hill, 8, plays with evacuee Skyler Smith, 7, at a shelter at St. Thomas Presbyterian Church in west Houston.
A man climbs out of a utility truck that got stuck in floodwaters Wednesday on Highway 96 in Lumberton, Texas.
Interstate 10 is closed due to floodwaters from Tropical Storm Harvey.
Adriana Perez, left, and Clair Hummel help remove drywall and boards damaged by floodwaters from Harvey from a friend's home Wednesday in Houston.
Workers begin repairs to a wall that was lost in the wake of Harvey on Wednesday in Rockport, Texas.
People line up to volunteer at NRG Center, which opened its doors to evacuees in the wake of Harvey on Wednesday in Houston.
In this Aug. 28 photo, a house in Port O'Connor, Texas displays a message for Hurricane Harvey on one of the plywood shutters put up before the occupants fled.
Mike Henry, center, lifts his leg onto a boat as members of the Louisiana Department of Wildlife and Fisheries help rescue him during flooding from Harvey in Orange, Texas, on Wednesday.
In this photo provided by Beulah Johnson, evacuees sit in the bleachers at the Bowers Civic Center in Port Arthur, Texas, on Wednesday after floodwaters inundated the facility overnight. Authorities said it's not clear where the evacuees will go.
A rescuer moves Paulina Tamirano, 92, from a boat to a truck bed as people evacuate from rising waters from Harvey in Houston.
Interstate 69 is covered by floodwaters from Harvey, in Humble, Texas, on Tuesday. Just two weeks ago, President Trump rolled back an order by his predecessor that would have made it easier for storm-ravaged communities to use federal emergency aid to rebuild bridges, roads and other infrastructure so they can better withstand future disasters. That decision is now being questioned with the Texas Gulf Coast and much of Houston under water in the wake of Harvey.
Volunteers and first responders work together to rescue residents from rising flood waters in Houston on Tuesday.
Evacuees make their way though water near the Addicks Reservoir as floodwaters from Harvey rise Tuesday in Houston.
Water from Addicks Reservoir flows into neighborhoods as floodwaters from Harvey rise Tuesday in Houston.
Rescue boats fill a flooded street as victims are evacuated Monday.
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