5 Inches in 3 Hours: What North Jersey's 'Once-in-a-Generation' Storm Means for Your Basement

A stalled front dropped more than five inches of rain on North Haledon in three hours on Sunday, September 13, flooding streets in Paterson and forcing nearly 20 water rescues. Here's what homeowners in Passaic, Bergen, and nearby counties should check before the next downpour.

How a slow-moving storm overwhelmed North Jersey drainage

The rain that hit Passaic and Bergen counties on Sunday, September 13 wasn't a hurricane remnant or a tropical system. It was a stalled front paired with a slow-moving area of low pressure that parked over North Jersey and refused to move on. That combination let a single band of thunderstorms train over the same towns for hours, and the Rutgers New Jersey Weather Network station in North Haledon recorded more than five inches between 7 and 10 a.m., with gauges in Harrington Park, Paramus, and West Caldwell topping five inches over the same window.

A Rutgers climatologist described the rate, not just the total, as the real story. An inch or two of rain per hour is already more than most storm sewers in older towns were engineered to move. When that rate holds for three hours straight, the system doesn't back up gradually, it fails all at once, which is exactly what turned streets in Paterson into moving water and forced nearly 20 rescues, including a wheelchair user carried off her feet by the current.

Why municipal storm sewers can't save your basement

It's tempting to assume that if the street floods, there's nothing an individual homeowner could have done differently. That's only half true. Municipal storm sewers move rainwater away from roads and yards, but the connection between that public system and a private home runs through equipment the town has no responsibility for: sump pumps, floor drains, backwater valves, and the grading around a foundation. When storm sewers surcharge under this kind of rainfall, water looks for the lowest point in the neighborhood, and in a lot of North Jersey homes, that's a basement with an aging sump pump that hasn't been tested since it was installed.

The failure mode is almost always mechanical, not exotic. A pump that's been sitting idle for a year can seize, a float switch can get wedged against the pit wall, or a battery backup can be dead exactly when the power flickers during a storm like this one. None of those are expensive fixes on their own. They're just easy to forget about until the one week a year, like this past Sunday, when they're the only thing standing between a storm and a ruined finished basement.

What to check this week, before the next system moves through

Forecasters have already flagged this pattern, a saturated ground combined with a stalled front, as one that tends to repeat through the fall shoulder season in the Northeast. That makes this week, not the day of the next warning, the right time to walk through a basement and drainage checklist rather than wait and hope.

Start with anything that moved water during Sunday's storm or should have. Run the sump pump manually with a bucket of water to confirm the float switch trips and the pump actually discharges outside, not just into a pipe that dumps six feet from the foundation. Check that downspouts extend at least four to six feet from the house, since a shortened extension is one of the most common and most overlooked causes of basement seepage. If the home has a floor drain, confirm it isn't the entry point for sewer backup during a surcharge event by asking about a backwater valve, which is a one-way check valve that keeps municipal sewage from being pushed back into the house when the system is overwhelmed downstream.

6 Things to Check in Your Home After a Storm Like This

Whether your basement stayed dry on Sunday or not, this is the checklist worth running before the next round of heavy rain moves through.

1. Test the sump pump manually: Pour a bucket of water into the pit and confirm the float switch trips, the pump primes, and it discharges well away from the foundation.
2. Check the battery backup: Storms that cause flooding often knock out power at the same time. A backup battery is only useful if it's actually charged and wired correctly.
3. Extend downspouts four to six feet: A downspout that dumps right at the foundation is one of the most common, and most fixable, causes of basement seepage.
4. Ask about a backwater valve: This one-way valve keeps a surcharged municipal sewer line from pushing wastewater back into a floor drain or basement fixture.
5. Clear gutters and grates: Leaves and debris from an early fall storm can clog gutters and street-level catch basins right when the next system arrives.
6. Photograph and document any water intrusion: If water did get in, timestamped photos help with insurance conversations, even for damage that ultimately isn't covered.

Frequently asked questions

Does homeowner's insurance cover this kind of flood damage?

Usually not automatically. Standard homeowner's policies typically exclude surface flooding and often exclude sewer or drain backup unless a specific rider was added. It's worth checking a policy's declarations page rather than assuming coverage exists.

Why did this storm cause so much flooding without a hurricane involved?

The rainfall rate mattered more than the storm's classification. Five or more inches falling in three hours is more water than most local storm sewers, especially in older towns, were designed to carry away.

My basement didn't flood this time. Do I still need to do anything?

A dry basement in one storm doesn't guarantee the next one goes the same way, especially if a sump pump or backup battery hasn't been tested recently. A quick inspection now is far cheaper than an emergency call during the next warning.

When should I call a plumber instead of handling this myself?

If a sump pump doesn't respond to a manual test, if there's any sewage odor near a floor drain, or if you're unsure whether a backwater valve is installed, that's worth a professional look rather than a guess.