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Fixing the problem The solution to the problem, like many a sappy musical, comes in two parts, with the second happening as a result of the first. The first thing to happen is a reconfiguration of the I-283/PA 283 interchange. A new plan would be primarily designed to accommodate 283 through traffic while not leaving Highspire and Turnpike traffic out in the cold. After the dust settles, 283 would actually be a continuous route from Harrisburg to Lancaster. Step two actually involves getting rid of the 283 designation. That's right, I said getting rid of 283. Interstate 283 connects one Interstate (83) to another (76) and therefore has an even first digit with the base of 83, hence 283. Once 283 is 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. The interchange 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 I-383 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.
One of the upsides of the layout is that is allows for a pretty painless construction process. First, the westbound thru traffic bypass is constructed and the old west-to-north ramp is closed.
Next, the new eastbound exit "bump out" is built and westbound exit lanes are built as well.
Once the new exit lanes are in place, work can begin on the eastbound "fly-over" thru traffic bypass.
After that, the old south-to-east and east-to-north ramps are closed and the remaining five ramps are relocated or rehabilitated.
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.
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. Reconstructing the old 283/283 interchange is the central key to creating I-383, and the rest of the work should be limited to clerical and signing adjustments.
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