Harvey, one of the most destructive storms in US history battered Texas for the fifth day on Wednesday claiming 30 lives and left thousands homeless even as Houston's mayor declared a nighttime curfew to prevent looting and opportunistic crimes.
Thousands of emergency rescue teams officials remained on their toes, helping people affected by the deluge. Weather official said parts of state are expected to receive heavy rainfall again.
At least 30 people have died in storm-related incidents, local officials confirmed. The toll could rise as they are pursuing reports of people lost in the torrential downpours unleashed since Friday.
Authorities announced the curfew - midnight to 5 AM - after police arrested a crew of armed robbers who were hijacking vehicles, and officials warned residents of people impersonating Homeland Security investigators. There also were fears of looting as thousands of houses lay partially submerged and abandoned.
Harvey was gearing up for another landfall near the Texas-Louisiana border. With this landfall expected, the devastation and misery could intensify, it said.
More than 100,000 Indian-Americans living in and around Houston have also been badly hit by the monstrous hurricane.
The Weather Service has issued a flash flood emergency - its most severe flood alert - yesterday night, The Washington Post reported.
The remnants of deadly Hurricane Harvey menaced Texas and Louisiana, while a reservoir west of downtown Houstonspilled overdue torecord-shatteringrainfall.
Officials in Houston were unable to determine the extent of the tragedy caused by one of the most destructive storms in the US history, authorities said.
Texas Governor Greg Abbott said Harvey is one of the largest disasters America has ever faced and warned against expecting anything resembling recovery any time soon, or a return to the way things were.
"We need to recognise it will be a new normal, a new and different normal for this entire region," he said.
Houston, the fourth-largest city in the US and the most populous in Texas, was still conducting emergency operations, with multiple road closures and no access to area hospitals for ambulances, after Hurricane Harvey, a Category 4 storm, made landfall on Friday night.
Harvey has since lost its intensity, leaving behind a trail of destruction that could take years to overcome.
The National Weather Service reported that Houston has already received more than 42 inches of rain due to Harvey.
Some parts of Louisiana have also seen more than a foot of rain, and the flash flood warnings were in effect for much of the Lake Charles region as the rainfall is expected to continue.
New Orleans is under a tornado and flash flood watch until tomorrow.