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TX: I-20 relocation at Ranger Hill

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oscar:
I suggest an Updates entry, saying I-20 was relocated (or "slightly relocated") between waypoints 358 and 361, to alert users that there was a change that they might want reflected in their list files, even if there is no change to the route file. People who want to view the change as declinching (not me) can use those points to indicate the part of the route they've no longer clinched. If the old and new alignments split within the footprints of the existing interchanges, that's close enough, never mind 1PPI. No need to add new points, or relabel existing points (the Updates entry will take care of that).

When I-80 in California was rerouted to the new eastern span of the San Francisco-Oakland Bay Bridge, I inserted new points at each end of the old alignment/new alignment split. The western split is so close to an existing interchange that I had to mark the resulting NMP as a false positive. Since that point is in use, I'd leave that alone, even though I didn't consider the bridge replacement as a de-clinch. Later, I traveled the new bridge, planning my trip to do that in the toll-free direction.

Duke87:

--- Quote from: yakra on January 16, 2022, 04:07:39 pm ---Again: 1PPI.

--- End quote ---

The new alignment doesn't deviate from the old until about half a mile west of exit 361 and well over a mile east of exit 358.

As of this writing Goog's satellite view shows this quite clearly: the new alignment is mapped but the old is on the satellite image. Select edit with iD on OSM and similar can be seen (for an open source).

yakra:
old alignment data ripped from shapefiles:

--- Code: ---495365-1827 http://www.openstreetmap.org/?lat=32.487083&lon=-98.562736
495365-1826 http://www.openstreetmap.org/?lat=32.488715&lon=-98.553823
495365-1825 http://www.openstreetmap.org/?lat=32.488987&lon=-98.552408
495365-1824 http://www.openstreetmap.org/?lat=32.489150&lon=-98.551719
495365-1823 http://www.openstreetmap.org/?lat=32.489555&lon=-98.550462
495365-1822 http://www.openstreetmap.org/?lat=32.489913&lon=-98.549549
495365-1821 http://www.openstreetmap.org/?lat=32.490280&lon=-98.548786
495365-1820 http://www.openstreetmap.org/?lat=32.490498&lon=-98.548410
495365-1819 http://www.openstreetmap.org/?lat=32.490901&lon=-98.547748
495365-1818 http://www.openstreetmap.org/?lat=32.491230&lon=-98.547309
495365-1817 http://www.openstreetmap.org/?lat=32.491677&lon=-98.546757
495365-1816 http://www.openstreetmap.org/?lat=32.491939&lon=-98.546450
495365-1815 http://www.openstreetmap.org/?lat=32.494803&lon=-98.543430
495365-1814 http://www.openstreetmap.org/?lat=32.495758&lon=-98.542426
495365-1813 http://www.openstreetmap.org/?lat=32.496501&lon=-98.541588
495365-1812 http://www.openstreetmap.org/?lat=32.497048&lon=-98.540802
495365-1811 http://www.openstreetmap.org/?lat=32.497517&lon=-98.539877
495365-1810 http://www.openstreetmap.org/?lat=32.497815&lon=-98.539015
495365-1809 http://www.openstreetmap.org/?lat=32.497938&lon=-98.538539
495365-1808 http://www.openstreetmap.org/?lat=32.498043&lon=-98.538012
495365-1807 http://www.openstreetmap.org/?lat=32.498122&lon=-98.537436
495365-1806 http://www.openstreetmap.org/?lat=32.498214&lon=-98.536466
495365-1805 http://www.openstreetmap.org/?lat=32.498377&lon=-98.534093
495365-1804 http://www.openstreetmap.org/?lat=32.498621&lon=-98.530870
495365-1803 http://www.openstreetmap.org/?lat=32.498688&lon=-98.529801
495365-1802 http://www.openstreetmap.org/?lat=32.498742&lon=-98.528689
495365-1801 http://www.openstreetmap.org/?lat=32.498958&lon=-98.523561
495365-1800 http://www.openstreetmap.org/?lat=32.499236&lon=-98.516673
--- End code ---
Use ESRI WorldImagery in wptedit.
The western divergence is just about exactly at existing point 358.
The eastern divergence is at about the 495365-1801 point. This is past the ramp gore, within the interchange footprint, and thus gets collapsed into 361.
I'm not looking at the distance to the center-point of the interchanges, but rather the interchange footprint as a whole.

Duke87:
*blink*

I was looking at interchange footprint and not just point location too. I think the reason I'm coming up with a different answer here is that I'm looking the point where the new roadway footprint and the old roadway footprint cease having any overlap as being where the new alignment diverges from the old. If you're looking at where the centerline begins to shift then... yes this is basically at the gore point of the exit at both ends. The alignment shift is so gradual here that you get a very different point of divergence depending on which definition you use.

So, we could go down the rabbit hole of asking which definition of old alignment diverging from new is more correct, but... no, it's not worth it. There is a definition of things by which what you've done is defensible so I'm content to let it be.

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