US rescuers battled to reach thousands cut off by flooding in towns across Vermont, New Jersey and upstate New York as the death toll from Hurricane Irene climbed towards 50.

Emergency provisions had to be airlifted on Tuesday to dozens of communities stranded by floodwaters as torrential weekend rains dumped by the massive storm system washed away roads and sent rivers cascading over their banks.

President Barack Obama dispatched senior officials to survey some of the worst of the damage as rescuers ferried thousands of people — including the elderly, small children and babies — to safety in rubber motorboats.

Although the much-hyped direct-hit on New York failed to translate into major damage or casualties in America’s most populous city, heavy rain in places like the Catskill Mountains proved a ticking disaster time-bomb.

Two days after the storm’s passage, marooned families were still waiting anxiously for the National Guard and firefighters to bring food and water to towns swamped by the floodwaters.

The main highway to Wilmington, Vermont was clogged with mud and Irene had turned other roads into deathtrap chasms after dumping two months worth of rain (8.3 inches, 21 centimeters) in less than a day.

“The problem is inaccessibility,” emergency operations supervisor Dave Miller said as teams struggled to pull trucks out of the sludge and remove fallen trees that had perilously dragged down power lines.

The drastic situation was mirrored in parts of New Jersey and upstate New York, where schools and community centers turned into makeshift Red Cross emergency shelters were nearing full capacity.

In Paterson, New Jersey, teams were rescuing and evacuating people non-stop under thankfully blue skies after the Passaic River crested 13 feet (four meters) above flood stage, its highest level since 1903