The Susquehanna River near Wilkes-Barre, Pennsylvania

Heavy rains caused by Tropical Storm Lee on Thursday forced the evacuation of tens of thousands of residents from the eastern US states of Pennsylvania and New York, as the Susquehanna River reached record heights.

At least five people in Pennsylvania and Maryland died as a result of the flooding. The storm killed four others when it first hit land on the US Gulf Coast last week.

In Wilkes-Barre, Pennsylvania and surrounding towns in Luzerne County and the Wyoming Valley over 70,000 residents who live in the flood plain were told to evacuate their homes and prepare to stay out until Sunday evening. Businesses and colleges were shut down. The river was expected to crest at 41 feet in Wilkes-Barre, threatening to eclipse the city’s dikes.

Upstream on the Susquehanna, officials in Binghamton, New York told 20,000 residents to evacuate as the river surpassed record flood levels and inundated the city’s downtown. The floodwalls in Binghamton, home to a New York state university campus, were built in the 1930s.

Wilkes-Barre’s dyke was rebuilt after the 1972 flood caused by Hurricane Agnes. The damage that year was the most costly in US history to that point, inflicting $2 billion in losses on Pennsylvania alone.

A number of towns along the Susquehanna saw the river surge over their levees Thursday afternoon, including Pittston, a small town across the river from Wilkes-Barre. About a quarter of the city was under water as of this writing, according to media reports.

Downstream in Harrisburg, Pennsylvania’s capital, officials ordered thousands of evacuations as the river appeared poised to reach record levels early Friday morning. Two towns in Maryland, Havre de Grace and Port Deposit, near where the Susquehanna empties into Chesapeake Bay, also ordered evacuations.

A little more than a week ago Hurricane Irene hit the Northeast, bringing with it heavy rains. As a result of Irene, the ground in Pennsylvania, New York, New Jersey, and Maryland was already saturated, and could not absorb the rains from Lee.

Lee has also been made worse by the simultaneous emergence of Hurricane Katia in the Atlantic to the east, and a high-pressure weather system over Ohio and Michigan to the west. As a result, Lee was funneled into a narrow area that roughly matches the Susquehanna watershed, which drains about 27,000 square miles of the Northeast.

Irene “really primed the pump” said Tom Graziano, chief of the Hydrologic Services Division at the National Oceanic Atmospheric Administration, “and now we’re adding this tremendous amount of rainfall.”

The flooding caused power outages in Wilkes-Barre and other towns. There were fears that chemical spills and damage to sewage and water treatment plants could result. As of this writing no major bridges had collapsed, but major damage to roads and parks had been reported in a number of locations.

It is unclear when the danger of flooding will subside. While the Susquehanna had crested in some towns in others it was reportedly still rising at a rapid pace. Governors in Pennsylvania and New York said they would seek federal disaster relief.

Tropical Storm Lee is the latest in a series of natural disasters that have tested the limits of America’s aging infrastructure and meager social safety system. The federal government, along with state governments, counties, cities, and towns, has sharply cut funding for emergency services in recent years.

This year Pennsylvania Governor Tom Corbett cut funding for the state’s Emergency Management by nearly one third, from $12.8 million to $9.69 million. Last weekend, even before the flooding in Pennsylvania and New York, the Federal Emergency Management Agency (FEMA) announced that its funding was running dangerously low.

The Pennsylvania areas worst hit by the flooding are among the poorest in the region. The Scranton and Wilkes-Barre metropolitan area—a former mining and steel region with a population of 563,000 people—has the highest unemployment rate in the state. Harrisburg has been teetering on the brink of bankruptcy for two years. Neither area will be able to absorb the economic dislocation caused by the flooding.