US President Donald Trump has arrived in Texas to survey the response to devastating Tropical Storm Harvey, the first major natural disaster of his White House tenure, as officials in Houston struggled to manage the record-breaking rains.You can watch his visit live, below.The slow-moving storm has brought catastrophic flooding to Texas, killed at least nine people, led to mass evacuations and paralyzed Houston, the fourth most-populous U.S. city. Some 30,000 people were expected to seek emergency shelter as the flooding entered its fourth day.Officials in Harris County, where Houston is located, said reservoirs built to handle drainage water were beginning to overflow on Tuesday. They urged residents to evacuate as they released water to alleviate pressure on two dams, a move that would add to flooding along the Buffalo Bayou waterway that runs through the area.Officials in Brazoria County, south of Houston, also called for immediate evacuations around a levee Columbia Lakes that had been breached by Harvey’s floodwaters.Some 3,500 people already have been rescued from high waters in the Houston area with police, firefighters and National Guard troops continuing to try to locate those marooned in high waters.