One-out-of-four commuters who normally take the Morris & Essex lines to Manhattan would have to stay home or find another ride to work.

Another 1,200 would have to head south instead of north on the PATH.

And 3,800 would have to split up in just the right way, between PATH, ferries and buses.

If all that happens, then transportation officials say they are prepared for the busiest hour of the morning commute on July 10 and for weeks afterward, when renovations to New York Penn Station will reduce train traffic to the world's busiest rail terminal by 25 percent.

However the numbers work out, commuters are bracing for eight weeks of chaos as work is done to repair the rails and switches that feed Penn Station.

NJ Transit plans to divert most of the 23,000 riders on the Morris & Essex Midtown Direct line from New York to Hoboken. That would more than double the number of people using the Hoboken terminal and send an unknown number of additional people to already crowded PATH trains.

Here's how it breaks down:

NJ Transit officials said they anticipate as many as 10,000 additional commuters going to Hoboken over a three-hour period ending at 10 a.m. — half of them during the busiest hour, from 8 a.m. to 9 a.m.

The Port Authority plans to send four extra PATH trains each hour from Hoboken to 33rd Street – enough to handle 3,080 people an hour.

A special New York Waterway ferry service from Hoboken to 39th Street is expected to handle another 1,800 per hour.

Additional bus service is planned that NJ Transit officials said could handle 2,880 more people between Hoboken and midtown.

Scott Ladd, a spokesman for the Port Authority, which runs the PATH service, said in an email this week that PATH would be able to “absorb the increase” in ridership “without too much difficulty unless there are unforeseen developments either at Penn Station in New York or in the PATH system over the time period involved.”

Commuters wary

Some commuters and transportation advocates were not nearly as confident, saying they expect PATH trains to be a bottleneck.

“PATH is going to be a big problem,” said David Peter Alan, chair of the Lackawanna Coalition, a rail commuter advocacy group. “That’s the elephant in the living room no one is willing to face.”

Some longtime Morris & Essex line passengers said they would take the PATH to midtown, as they did before Midtown Direct service into the city began operating in 1996, even though they expect the PATH to be overcrowded.

“I will go to Hoboken like I used to do,” said Walter Zweifler, an 85-year-old business appraiser from South Orange who travels into New York to visit clients. “Do I like it? Hell no. Is there anything I can do about it? Absolutely not. ... I will take the PATH — even though it’s obvious the PATH won’t be able to accommodate them. What else do we have?”

Transportation officials point out that they have been through this before, following a derailment at Penn Station earlier this year, when PATH trains handled a crush of additional riders. This time, they say, there has been ample opportunity to prepare.

Conflicting numbers

But as the day of reckoning approaches, transportation officials have contributed to confusion by releasing conflicting numbers.

Ladd said in an email this week that the Port Authority anticipated an additional 7,600 NJ Transit riders “during each of our peak commuting periods: 7-10 a.m. and 4-8 p.m.” That was similar to what other Port Authority officials had been saying.

Those statements, however, appeared to be in conflict with some numbers being released by NJ Transit. And some of NJ Transit’s numbers conflicted with its own numbers released just days earlier.

On Friday, Port Authority and NJ Transit staff, after conferring about the figures, said that 9,500 additional passengers would be heading to Hoboken during the morning rush hours. NJ Transit officials said they came to that number by using a computer model.

That model predicts 25 percent of 13,000 morning commuters who usually take Morris & Essex line trains to Manhattan would not go to Hoboken.

They could take early morning Morris & Essex Midtown Direct trains that will arrive at Penn Station before 7 a.m. Some might use the expanded bus service from South Orange. Others might get off at Newark Broad Street, take light rail to Newark Penn Station and hop on another train into Manhattan. And still others could work from home or take vacations.

NJ Transit said that leaves between 9,000 and 10,000 additional passengers going to Hoboken between 7 a.m. and 10 a.m.

During the busiest hour, from 8 to 9 a.m., the same computer models showed 6,600 Morris & Essex passengers being whittled down to 5,000. Models show that 25 percent of that number will head to the World Trade Center instead of to midtown. NJ Transit workers will help to direct others to the ferry and the bus, officials said Friday.

But for all of the computer modeling and projections, commuter advocates say there is much that remains unknown.

First days will be tough on commuters

They anticipate a rough first day followed by commuters sharing their stories on social media and changing their routines – some going in early or late, and others sharing rides or taking an Uber to train stations like Secaucus, where they would attempt to get a one-seat ride into New York.

“These commuting patterns are set,” said Charles Walsh of the North Jersey Rail Commuting Association, a rail commuting advocacy group. “It’s like throwing a deck of cards into the air – you don’t know how it’s going to land.”

Commuters this past week said they are readying for an extended period of discomfort – and a few even said they would consider driving into New York City to avoid getting on and off trains that they expect to be delayed in any case. Others said they might take an extra week of vacation.

But most said they would continue their routines and come to grips with the anticipated delays.

“The Hoboken terminal is clearly decrepit,” said Matthew Horisk, of Cornwall, New York, who commutes on the Port Jervis line to Hoboken every day. “So any added people we’re putting into the terminal and then putting onto PATH trains that are already at or near capacity seemingly is a bad thing to do.”

Ryan Renzi, of Metuchen, who was riding a Northeast Corridor train into Penn Station this week, said he’s already inured to delays of up to 45 minutes into and out of Penn Station caused by repairs and maintenance work that’s been ongoing since two derailments earlier this year.

In May, NJ Transit’s on-time performance at Penn Station during the morning peak hours was just 46 percent. In contrast, the Main-Bergen line, which runs to Hoboken, was on time 97 percent of the time.

“I don’t get the opportunity sometimes to be with my family,” Renzi said of the evening delays. He added that he is planning to take two weeks of vacation this summer, instead of the usual one week, to avoid at least some of the anticipated commuting problems: “A little staycation just to be with family.”

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Some PATH riders who live in Hoboken said they were aware of the Penn Station renovations and expected that it might have some impact on them, but had not been aware of the scope of the potential problems. Several said they did not anticipate using an alternative to the PATH.

One woman, Barbara Gombach, said she might take the bus or the ferry because “it’s too scary on these platforms” when the PATH trains are crowded.

Catherine McClellan, a fundraiser for a nonprofit organization in Manhattan, said she just moved from Park Ridge to Hoboken to swap a commute on the Pascack Valley line for a much shorter ride on the PATH.

“I chose my apartment because of how close it was to the PATH,” she said.

Zweifler, the 85-year-old from South Orange, said “there’s no logic to someone taking their car into New York under any conditions” and that he would not consider the bus because it would be uncomfortable and he does not believe it would be faster than the PATH. He said that he accepts the anticipated delays as part of the commute.

“I will probably take it and grit like the rest of us and make the best of things,” he said.