There will be multiple lane closures as of 9 p.m. Friday. The complete switch over will take until 8 a.m. Saturday.
The plan is for four lanes of northbound/westbound traffic on the new bridge and four lanes of southbound/eastbound traffic remaining on the old Tappan Zee Bridge.
Workers will be reconfiguring the landings and striping the lanes at both ends of the new 3.1-mile crossing.
In Westchester, the northbound/westbound Thruway exit 9 (Tarrytown - Sleepy Hollow - US Route 9) on-ramp from Route 119 will be closed at approximately 9 p.m.
Drivers will be detoured approximately one mile east on Route 119 to access the northbound Thruway (see map below). The on-ramp is scheduled to reopen by 6 a.m. Saturday. The exit 9 off-ramp to Route 119 will remain accessible from the northbound Thruway.
In Rockland, the northbound/westbound Exit 10 (Nyack - South Nyack - US Route 9W) off-ramp will also be closed at approximately 8 p.m. The off-ramp is scheduled to reopen by 6 a.m. Saturday. The detour route is detailed in the map below.
Variable Message Signs along the Thruway and other highways in the region have been activated to inform motorists of the traffic shift.
In the fall, Westchester-bound traffic will be shifted from the old bridge to the first span. Traffic will consist of four lanes in each direction, separated by a concrete barrier to allow for construction of the second span to be completed.
All lane closures are subject to change due to traffic, weather or emergency situations. Please visit http://www.thruway.ny.gov/travelers/map/ for real-time information regarding traffic conditions.