Looking at this I-69 HPC stuff it is very confusing:
Corridor from Sarnia, Ontario, Canada, through Port Huron, Michigan, southwesterly along Interstate Route 69 through Indianapolis, Indiana, through Evansville, Indiana, Memphis, Tennessee, Mississippi, Arkansas, Shreveport / Bossier Louisiana, to Houston, Texas, and to the Lower Rio Grande Valley at the border between the United States and Mexico, as follows: [I-69]
Right, that makes sense. Sarnia - Port Huron - Indianapolis - Evansville - Memphis - MS - AR - Shreveport / Bossier - Houston - Lower Rio Grande Valley (unspecific where in that valley) is I-69 and I-69 is the corridor. The bit through AR is a defined future bit of the corridor, but not currently part of the corridor as it isn't I-69.
Then there's more detail, where it goes crazy:
A. In Michigan, the corridor shall be from Sarnia, Ontario, Canada, southwesterly along Interstate Route 94 to the Ambassador Bridge interchange in Detroit, Michigan.
B. In Michigan and Illinois, the corridor shall be from Windsor, Ontario, Canada, through Detroit, Michigan, westerly along Interstate Route 94 to Chicago, Illinois.
So I-94 is the route of I-69 between Sarnia and Indianapolis? Chicago wasn't mentioned in the summary above. Nor Windsor...
The language here leaves no room for I-69 to also be the corridor in MI. Really poor writing.
C. In Tennessee, Mississippi, Arkansas, and Louisiana, the Corridor shall--
i. follow the alignment generally identified in the Corridor 18 Special Issues Study Final Report; and
ii. include a connection between the Corridor east of Wilmar, Arkansas, and west of Monticello, Arkansas, to Pine Bluff, Arkansas
Fine, though does that mean that the I-530 extension is part of I-69?
In the Lower Rio Grande Valley, the Corridor shall-
i. include United States Route 77 from the Rio Grande River to Interstate Route 37 at Corpus Christi, Texas, and then to Victoria, Texas, via United States Route 77; [I-69 East]
I-69 E defined in law from Victoria to the border.
ii. include United States Route 281 from the Rio Grande River to Interstate Route 37 and then to Victoria, Texas, via United States Route 59; [I-69 Central]
wait a minute. I-69C is legally defined to Victoria, and includes a three-way junction with itself at George West (or does it then, on arriving at I-37 north of Three Rivers take I-37 to US 59?)
and
iii. include the Corpus Christi North-side Highway and Rail Corridor from the existing intersection of United States Route 77 and Interstate Route 37 to United States Route 181, including FM511 from United States Route 77 to the Port of Brownsville.
Where's Laredo? Laredo isn't explicitly defined as part of the I-69 corridor 18, and can therefore have whatever number TX DOT, AASHTO and the FHWA choose to give it. Ditto the Texarkana spur, US 83 and TX 44. However, the North-side Highway is part of I-69 (with no legally defined suffix).
And how can the Corpus Christi North-side Highway and Rail Corridor also be including FM511? Which is also I-69 with no legally defined suffix.