A huge clean-up is taking place in the north east of the US after dozens of people died following record-breaking rainfall from the remnants of Hurricane Ida

At least 46 people in five states died as storm water cascaded into people’s homes and engulfed cars, overwhelming urban drainage systems never meant to handle so much rain in such a short time.

The toll was highest in New Jersey, where 23 people died in heavy rains late Wednesday and early Thursday.

The majority drowned after their vehicles were caught in flash floods, some dying in their submerged cars, some getting swept away after getting out into fast-moving water.

Floodwaters and a falling tree also took lives in Maryland, Pennsylvania, Connecticut and New York. In New York City, 11 people died when they were unable to escape rising water in basement apartments.

Authorities said the work of searching for possible victims and identifying the dead was not over.

Work also continued to haul away ruined cars, clean mud and debris from streets and restore services on transport systems.

Parts of New York City’s subway system remained offline on Thursday night as workers repaired flood damage.

Leaders in some states also pledged to examine whether anything could be done to prevent a catastrophe like this from happening again.

New Jersey and New York have both spent billions of dollars improving flood defences after Superstorm Sandy hit the region in 2012 but much of that work was focused on the coasts and tidal floodplains.

President Joe Biden has approved disaster declarations for both states. The federal action was issued to mobilise agencies to provide assistance to areas hardest-hit by the storm.

New York Governor Kathy Hochul said the region needed to turn its attention to storm systems unprepared to handle a future of more frequent inland flash flooding due to global climate change.

“One thing I want to make clear: we’re not treating this as if it’s not going to happen again for 500 years,” she said.

Ida came ashore in Louisiana on Sunday, then moved north as the fifth-strongest storm to hit the US mainland, then moved north and east dumping torrential rain all week.

Forecasters had warned of potentially dangerous hazardous flooding but the ferocity of the storm caught the nation’s most densely populated metropolitan corridor by surprise.

One person died in Maryland and at least five in Pennsylvania, where some neighbourhoods alongside the Schuylkill River in Philadelphia remained partly underwater.

A Connecticut state police sergeant died after his cruiser was swept away. In one New York City basement apartment, a two-year-old boy died along with his parents when they could not escape rising water.

The National Weather Service said the storm also spawned at least 10 tornadoes, the most serious of which destroyed homes in Mullica Hill, New Jersey, south of Philadelphia.