#1 The Port Authority is paying for it

The roughly $450 million bridge deck replacement is part of a $1 billion rehabilitation of the aging span, and Gov. Chris Christie managed to get

. The move has caused some controversy – the bi-state agency is only allowed to fund transportation projects outside of its network with approval from both New Jersey and New York legislators – but the Port Authority defended the move by saying the Skyway is an access road to the Lincoln Tunnel.

Yes, the Lincoln Tunnel. Though the Skyway leads directly into the Holland Tunnel, the bi-state agency can't legally build access roads to the Hollan Tunnel because construction of that tube predates the agency's creation.

#2 It’s going to last a long, long time

The lane closures begin on Saturday, April 12. State officials say the bridge deck replacement will take two years, and they don’t foresee it ending early. Crews will work anywhere from 20 to 24 hours per day and at least six days a week. The DOT says if they see work isn’t progressing fast enough, they will ask for a seventh day.

#3 The closures affect northbound traffic only

Southbound traffic headed to Kearny and Newark will be able to use the Skyway for the entire duration of the project, though the Broadway ramp in Jersey City will be closed in both directions. Once the bridge deck on the northbound side is replaced, southbound traffic will use the northbound lanes as the deck on the other side is replaced. DOT officials say if they kept the bridge open for only northbound vehicles, traffic would back up beyond the Holland Tunnel and onto New York City streets.

#4 The DOT wants you to leave your car at home

State officials have arranged for thousands of extra seats on trains and buses headed to New York, and they’re hoping regular commuters will decide to skip driving and learn to love public transportation instead. NJ Transit has added bus capacity and additional trains on the Morris and Essex, Raritan Valley and North Jersey Coast lines, leading to 3,000 extra seats each morning peak period. There will also be an express bus from the Sears in Watchung to Newark Penn Station, where riders can then take PATH trains into New York. The Port Authority, meanwhile, has increased the frequency of PATH trains that it says will allow 6,000 more people to ride the rail line in the morning.

#5 It will cost you more

The DOT believes most drivers who normally use the Skyway will now use the New Jersey Turnpike Extension, where the DOT has opened up a third lane of traffic to handle all the extra cars. Toll rates on the extension are significantly higher than they are elsewhere on the state roadway. It costs $2.45 at peak periods to travel the roughly eight miles between Exit 14 (Newark Liberty International Airport, I-78, Routes 1&9) and Exit 14C (the Holland Tunnel). The toll is just as much to travel the 33 miles from Exit 2 in Woolwich to Exit 5 in Westampton. And even if you take one of the non-Turnpike detours, you’ll likely pay more for gas, since none of the routes are as direct as the Skyway and there will probably be more congestion.

#6 If you plan to cut through Jersey City, think again

The city has approved a host of new turn restrictions that, while intended to keep congestion to a minimum, will also serve to discourage drivers from using local streets as a detour. The city will also have 50 cops stationed in various locations to keep you from making those newly forbidden turns.

#7 Leave home early

Especially in the first few days of the shutdown, there will be a lot more drivers on the road who are taking a new route to work, so plan on spending more time sitting in traffic. And look out for drivers paying more attention to their GPS than to the road.

#8 No one really knows what to expect

The state has never shut down the northbound lanes of the Skyway for this length of time, so who knows what will happen? A state official said it could be “car-mageddon.” Jersey City Public Safety Director James Shea conceded city officials are “just guessing” about the effects of the lane closures. We won’t know until April 14, the first Monday after the Skyway lane closures start.

#9 The ride home may stink, too

Only the northbound lanes are closed, but who knows what effect the closure (and bridge construction) will have on the evening rush hour? Motorists may be confused and think the entire bridge is shut down, clogging the alternate routes at night, too.

#10 Construction on the lower level of Route 139 will continue

The DOT is suggesting drivers take Routes 1&9T to Route 139 to the Holland Tunnel instead of the Skyway, but construction on Route 139 will leave only one lane open eastbound (between the Tonnelle Circle and the tunnel) for the duration of the Skyway shutdown. Westbound, two lanes will be open except at some points overnight when one of the lanes will close.

The DOT is suggesting motorists stay updated via 511nj.org and on twitter – @skywayrehab – so you should check them before you leave every morning to see if, for instance, the Lincoln Highway Bridge is scheduled to rise during the commute. You can also find information on pulaskiskyway.com.