The storm has displaced more than 1 million people, with 46 feared dead from flooding that paralyzed Houston.
President Donald Trump arrived in Houston on Saturday to witness the devastation wrought by Hurricane Harvey, which pounded America's fourth-largest city with apocalyptic floods that killed dozens and wrecked homes and businesses.
The sprawling Texas megacity was taking tentative steps back to normalcy after a week of acute flooding that damaged 40,000 to 50,000 homes and sent tens of thousands fleeing to emergency shelters.
The White House has asked Congress for $7.85 billion for Harvey-related "response and initial recovery efforts," calling it a "down payment" on the long-term cost of recovering from the record flooding.
TRT World's Sara Firth reports.
Harvey has been blamed for at least 42 deaths thus far and tens of billions of dollars of damage.
Trump and first lady Melania landed at a Houston air base late Saturday morning and were whisked off in a convoy of dark SUVs accompanied by a delegation that included Texas Governor Greg Abbott.
The president is returning to Texas for his second visit since the mega storm hit, and will also visit neighbouring Louisiana later in the day.
Trump on Tuesday stopped in the coastal city of Corpus Christi and the state capital of Austin, after which he tweeted that he witnessed "first hand the horror & devastation caused by Hurricane Harvey" – though he did not, in fact, tour any flooded areas or meet with any victims.
And as floodwaters receded in Houston, nearby cities such as Beaumont – which had lost its water supply – and Port Arthur struggled to recover.
One week after Harvey slammed into southeast Texas as a Category Four hurricane, rescuers were still out searching for people still inside flooded homes.
The White House's request for nearly $8 billion in emergency storm aid – made in a letter late Friday to House Speaker Paul Ryan – was $2 billion more than what the White House was expected to request, suggesting a rapid rise in needed funding as the scale of the disaster becomes clear.
White House budget director Mick Mulvaney, who said the administration would later be seeking an additional $6.7 billion for disaster relief, called on Congress to lift the US debt ceiling, warning that otherwise the outlays could be affected.
Meanwhile, rescuers in Port Arthur were still evacuating residents who refused to leave their homes during the storm.
Houston Mayor Sylvester Turner said most of the city was "now dry," but urged residents living near two overflowing reservoirs to leave their homes.
Officials said most of the 15,000 to 20,000 area residents have left. Some, however, were holding out, straining emergency workers who have to maintain services to them, including providing them with water.