1950s: Planning The route of what became I-84 through New York state began in the late 1940s, when the then-New York State Department of Public Works (now NYSDOT) was planning Gov.
Thomas Dewey's proposed
Thruway system. The plan was for the Thruway's main line to cross the river between Newburgh and Beacon, an area then in the middle of a gap in fixed river crossings. The remainder of the expressway would be toll-free. Politicians in the Newburgh area had also been lobbying for a bridge over
Newburgh Bay, as the
ferry service in that section of the river was becoming financially nonviable. In 1951 they were able to authorize test
boring in the riverbed to see if a bridge was feasible. It was, but their counterparts further up the river got legislation passed that prohibited any construction of the Newburgh Bay bridge until the
Kingston–Rhinecliff Bridge was completed. By the early 1950s the road plan had changed. The Thruway had been rerouted to cross the Hudson at the present site of the
Tappan Zee Bridge. Dewey suggested that the future I-84 be built as a separate toll road instead. After the passage of the
Federal Aid Highway Act of 1956, during the
Averell Harriman administration, state officials changed it back to a free road in order to get federal funding for the project. It remained on paper as other New York Interstates got underway.
1960s–70s: Construction Construction began in 1960 after the new governor,
Nelson Rockefeller, promised to expedite it during his campaign by building a single span, within the limits of what the state could afford without federal aid. The new plans called at first for a freeway connection for I-87 from Beacon to the
Bronx and a concurrency across the river. After that project was cancelled after
heavy local opposition. I-87 was routed to join I-84 at Brewster (where it would have followed the route of the current I-684). The first segment, the between the Thruway mainline in the
Town of Newburgh and US 9 in Fishkill, was opened November 2, 1963. On October 1, 1968, the section between NY 17M in New Hampton and NY 17 in Middletown was opened. On April 2, 1969, the section from the Taconic Parkway to NY 311 was opened. On August 27, 1970, the bridge over the Delaware River between Matamoras and Port Jervis was opened. On October 20, 1970, the section between Mountain Road in Greenville and NY 17M in New Hampton was opened. On May 12, 1971, the section between NY 311 and the interchange with I-684 in Brewster was opened, rendering all sections of the highway east of the Hudson River as open. The last segment to open was the one between NY 208 and the Thruway, on July 1, 1971.
Effect on western Orange County state highways The highway's route number prompted the renumbering of several existing state routes in western Orange County, where there was already an
NY 84. To avoid confusion, the NY 84 designation was eliminated and replaced with other routes in the mid-1960s. The portion south of
US 6 at
Slate Hill became
NY 284 while the section of NY 84 north from
Middletown to its northern terminus at
NY 17K in
Montgomery was added to
NY 211, which had previously terminated at its junction with
NY 17M and NY 84 in Middletown. The rest of NY 84 remained part of US 6 and NY 17M, which NY 84 had
overlapped through Middletown. Lastly,
NY 416 was truncated to its current northern terminus just south of Montgomery rather than ending at 17K as it had before. In addition, New Jersey renumbered its own
Route 84 to
Route 284 to match New York renumbering NY 84 to NY 284.
Improvements Montgomery
quad showing NY 84/416 along current route of NY 211. With I-84 complete soon after from
Scranton to
Hartford, the heavy traffic created
traffic jams at the
bottlenecks at either end of the Newburgh-Beacon Bridge. In 1975 a second span was approved. It was opened on November 1, 1980, almost 17 years to the day traffic first crossed the original span. Two lanes could still not handle all the traffic, and four years later, in 1984, the old bridge was reopened after renovations. The first was the US 9 exit, revamped in 1999 at a cost of $25 million. and completed in December 2009. The new exit also replaced 13 old buildings with a few new ones: a separate toll plaza to handle traffic entering the Thruway (the existing toll plaza is now dedicated to exiting traffic), offices and garages for NYSTA and the
New York State Police. The new buildings use
green techniques to minimize energy use such
daylighting and
rainwater collection. The ramps have been rerouted, using six new bridges and of roadway, so that almost all traffic from routes 17K and 300 now use the latter route to access both Interstates. The existing connector from the toll plaza to NY 17K remains as an
E-ZPass–only lane from that highway to the northbound Thruway. After lengthy litigation by
environmental groups concerned about the impact on nearby
Stewart State Forest, in 2005 construction began on exit 32 (then exit 5A). Local road Drury Lane was upgraded and widened into newly designated
NY 747 to allow easier access to
Stewart International Airport via an almost-full
diamond interchange. It was completed in November 2007, at the same time the briefly
privatized airport was turned over to the
Port Authority of New York and New Jersey with the intent of making it the
New York City metropolitan area's fourth major airport. The Thruway Authority's involvement with the road would have ended in 2006 when its board voted to transfer the highway back to the state DOT, a move it suggested did not commit it to doing so. The proceeds would have covered NYSTA's expenses in eliminating the toll barrier for a year on
I-190 south of
Buffalo. This was seen as an election-year move to help
Republican candidates in
Western New York. But residents of the mid-Hudson region felt NYSTA had done a better job
plowing the road in winter, and Thruway workers assigned to I-84 feared having to move or working for the DOT at lower pay and with different
union representation. In 2010, maintenance fully reverted to DOT. With the state facing financial difficulties in the
slow economy, Governor
David Paterson decided that DOT could save a few million dollars doing the work itself. In August of that year, the department bought $6 million worth of new equipment and hired 54 new employees to handle maintenance duties on the highway. In October 2010, Thruway insignia and signs indicating its maintenance responsibilities were removed from the roadway, and authority employees assigned to the road began transferring to jobs elsewhere, after the union waived several contract provisions to smooth the transfer.
New York State Troopers who patrolled the road were reassigned from Thruway-based Troop T to Troop F in Orange County and Troop K in Dutchess and Putnam Counties, which cover the west and east sides of the Hudson respectively. At the DOT's request, the two state police substations in Wallkill and East Fishkill remained open. In 2019, a $13.9 million project was completed that rebuilt the overpass carrying traffic over
US 9W in Newburgh, in order to provide better clearance for truck traffic below on Route 9W and to meet current interstate highway standards. Also in 2019, the exits were renumbered from sequential to mile-based as part of a sign replacement project by NYSDOT, in accordance with
MUTCD regulations. The Putnam County section of I-84 was changed to mile-based in June, with Dutchess County's exits renumbered before September 2. exits west of the Hudson have been fully renumbered up to the NY 17 interchange. Eastbound, NY 208 is fully renumbered in that direction but has both exit numbers on its signage approaching eastbound.
Incidents Many
traffic accidents, some fatal, have caused traffic jams and closures since I-84 was opened. One was notable for the type of vehicle involved; another led to a still-open
murder investigation.
Air accident On August 6, 1976, drivers along I-84 near exit 18 (
NY 311; now exit 61) in the
Putnam County town of
Patterson saw a low-flying
helicopter cross over the Interstate and then get entangled in the
power lines passing overhead. The craft flipped over and fell onto the eastbound lanes of the highway. Both pilot and passenger were killed, and 4,000 customers in the area
lost power. A traffic backup of several miles was rerouted onto the road's
shoulder around the crash site until the road was reopened two and a half hours later.
Murder investigation A
road rage incident on the side of the highway led to the death of Richard Aderson in 1997. Aderson, an assistant
superintendent at the
Valley Central School District in Montgomery, was returning to his
LaGrange home on the evening of February 5, 1997, when he had a minor collision with a relatively new green
Jeep Cherokee carrying what appeared to be
New Hampshire license plates just before crossing the Newburgh–Beacon Bridge. The two drivers pulled over near what was then exit 12 (now exit 44), and after a brief argument the other driver
shot Aderson and left the scene. Aderson was able to give the
9-1-1 operator he called on his
cell phone a description of his assailant and the vehicle before dying at the scene. A
police sketch based on Aderson's description has been widely circulated and is still posted prominently in
kiosks at the freeway's rest areas. The case has been dramatized on both ''
America's Most Wanted and Unsolved Mysteries''.
2023 bus crash On September 21, 2023, a chartered bus carrying ninth-grade members of the
Farmingdale High School marching band from
Long Island to a weekend at a camp in Pennsylvania suffered a tire failure along westbound I-84 in Wawayanda near
Slate Hill and rolled down a slope into the highway's median strip. Many students were injured, some critically, and two adults on the bus were killed. The highway was closed in both directions between exits 4 and 15 (formerly exits 2 and 3), with traffic diverted onto US 6, in order to clear the accident and create a landing zone for helicopters to evacuate the most seriously injured to
Westchester Medical Center. At the end of the year, the
Federal Highway Administration approved the addition of a crash gate for emergency vehicles, the absence of which had hampered response to the crash, along that stretch of the interstate. ==Exit list==