Brian Troutman Land

I-383 – Harrisburg to Lancaster

by on Nov.01, 2004, under Amateur Counsel, Highways

Mounting Traffic on I-283 at Highspire

Mounting Traffic on I-283 at Highspire

Interstates and US route numbers follow (or are supposed to follow) strict numbering guidelines, but state departments of transportation can number any state route as they please and will sometimes use this liberty to bridge psychological gaps in the Interstate network or keep alive a familiar designation that has officially been retired. For example, US 309 once ran from Philadelphia to Wilkes-Barre and beyond, but when it was decommissioned in 1968, PennDOT decided to keep the number on life support as PA 309. Also witness PA 581 that runs from I-81 eastward into Harrisburg. It could be Interstate 581, although it might not meed Interstate technical standards, but in any case, it serves the purpose that a true I-581 would serve.

Then we have central Pennsylvania’s “283”, which comes in two formulas: I-283 and PA 283. The two routes are not continuous, but in a way, the duo replaces the deceased US 230, a route connecting Harrisburg to Lancaster and all of the towns in between. The Interstate portion connects I-83 to the Pennsylvania Turnpike (I-76) near Highspire, and the state route portion runs from Eisenhower Boulevard in Highspire to US 30 in Lancaster. The two segments meet at a full eight-ramp cloverleaf.

The trouble with this arrangement is that most southbound vehicles are not headed for the Turnpike; they are going to the airport, to Middletown, Elizabethtown, or Lancaster and are funneled through the smallest of the four loop ramps. Come through this section of I-283 during rush hour, and you’ll see a backlog of vehicles in the right lane waiting to fight their way onto the PA 283 ramp. In recent years, PennDOT has slightly reconfigured the interchange area so that I-283 southbound’s right lane is dedicated Exit Only for PA 283 traffic, but this piecemeal solution does not really solve the issue.

The solution that I came up with is somewhat of a compromise; it’s not what you’d design if you were starting with an open field and a ton of federal money, but it is relatively cost-effective configuration that would serve the traffic needs of the Harrisburg-Lancaster corridor admirably. The end product is essentially a three-way directional interchange with a five-ramp partial cloverleaf attached like a Siamese twin. Sort of.

I-383: Harrisburg/Lancaster/Turnpike Interchange

I-383: Harrisburg/Lancaster/Turnpike Interchange

After construction of the interchange, the 283 designation could be retired and replaced by 383. Once the interstate forms an uninterrupted route to Lancaster, it will no longer end at an Interstate; it will end at US 30 and should therefore have an odd first digit. Since PennDOT uses the number 183 on a state route in rural Berks County, the next logical choice would be 383. It could be 583 or 783 (you get the picture), but “three eighty-three” has a nice little alliteration to it. As a result, the City of Lancaster would lose the dubious honor of being the largest city in Pennsylvania not served by an Interstate.

Obviously, the setup has a couple of downsides. Most notably, the interchange includes a left exit for westbound I-383 traffic headed to Highspire and the Turnpike and a left entrance for Turnpike traffic headed westbound onto I-383. Of course in the United States (or any other country that drives on the right), on- and off-ramps should be on the right, but this problem is somewhat mitigated by the high-volume nature of the interchange and also by the geometry of the two main exit ramps, both of which could be safely approached at 55 mph. An arrangement using only right exits and entrances could be created, but that would also be more difficult to construct, lead to a much higher price tag and probably require tighter turns in the ramps.

The other drawback is the permanent removal of the Highspire to Harrisburg ramp (PA 283 East to I-283 North), and I’m sure that this action would be unpopular with the Pennsylvania Turnpike Commission bigwigs who use the ramp as a shortcut to their Gridiron Breakfast at the Swatara Eat ‘n Park. But in this case, the “greater good” probably means giving the exiting Turnpike traffic more than a few feet in which to get in the appropriate lane for Lancaster or Harrisburg. The Swatara interchange (currently I-283 exit 2) is just a short drive down Eisenhower Boulevard and can handle the motorists who are heading north and west. Alternately, the existing ramp could be left in place, but that would not address the issue of having such a short distance between the toll plaza and the eastbound I-383 exit ramp. Yet another option would be to add a left turn lane on the old PA 283 right of way and construct a westbound on-ramp. Then again, the traffic volume probably doesn’t warrant the construction, and we might not want drivers turning left against the exit traffic that is coming from the opposing direction at 50 or 60.

I-383 Interchange Alternatives

Overall, the interchange solves the problem and does it well. The plan calls for only two new overpasses—major high-cost items in road construction—the rest of the elevation adjustments could be accomplished with retaining walls and backfill. The eastbound bypass lanes would gently rise about 16 feet to clear the westbound on-ramp, rise another 16 feet to pass over the westbound off-ramp, and finally lower to resume the elevation of the existing roadway.

The entire route’s milemarkers would be renumbered starting at the Eisenhower Interchange (I-83), and exits numbers would ascend eastward from there. (The entire route would be marked on an east-west orientation. Oddly enough, (and strictly by coincidence) the Swatara interchange, which was Exit 1 for about 30 years, became Exit 2 under the mileage-based interchange numbering but would return to Exit 1 with the I-383 exit numbering.

I-383 Westbound Signage

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