"Reserved" Interstate Highway Designations

[andy3175]

While looking for something else, I found this TX DOT webpage that describes "reserved" numbers for I-x10 and I-x35 (Scroll to bottom of the link):

http://onlinemanuals.txdot.gov/txdotmanuals/smk/interstate_highway_numbering.htm

Section 5: Interstate Highway Numbering
Original Numbering System
The original numbering system for interstate highways established that:

north-south routes end in 5, beginning with 5 on the west coast and increasing on routes east of IH-5
east-west routes end in zero, beginning with 10 in the south and increasing on routes north of IH-10.
Current Numbering System
After the initial interstate routes were designated, additional corridors became eligible for interstate highway funding. Since the initial routes had used all the available numbers ending with "0"  and "5,"  an alternate numbering system was developed using even and odd numbers, as follows:

Odd numbers designate routes that generally run in a north-south direction.
Even numbers designate routes that generally run in an east-west direction.
The number selected would generally fall in the normal sequence between two existing interstate routes. For example, IH-27 is located between IH-25 (New Mexico, Colorado, Wyoming, etc.) and IH-35 (Texas, Oklahoma, Kansas, etc.).

Loops
Interstate loops use three digits; the first digit is an even number, while the last two digits are associated with the interstate highway that carries the major traffic stream.

Business Loops. Interstate business loops typically retain the number of the interstate highway traversing the city or town and use a green route sign.

Interstate Loops in Texas. Texas interstate loops (both existing and possible) are as follows:

Interstate Loops in Texas
Loop Number Location
IH 210 El Paso (possible)
IH 235 Austin (possible)
IH 410 San Antonio
IH 435 Waco (possible)
IH 610 Houston
IH 635 Dallas
IH 810 Beaumont (possible)
IH 820 Fort Worth

Has anyone heard of these other I-x10 and I-x35 potential Interstate highway designations in Texas?

Regards,
Andy

[NE2]

Huh. Almost certainly something Texas has decided on their own, rather than AASHTO/FHWA. And why no smaller x20s?

It could be completely made up by whatever intern wrote that manual. But with Texas not avoiding number duplication, they probably would have started with the lowest numbers otherwise.

[kurumi]

I wonder if Alabama contemplated the same thing for its x59's.

[FreewayDan]

It doesn't list possible interstate spurs either, as well as the current ones in Texas: I-110 in El Paso, the unsigned I-345 in Dallas and I-369 in East Texas.

[Bobby5280]

I think it's anybody's guess how any available 3-digit Interstate numbers may be used in Texas. But it's fun to guess about the possibilities. Perhaps many of the available route numbers might never be used considering how the federal government has changed its funding formulas on Interstate highway construction and how Texas is funding some of its new super highways. Of course things could change depending on how the political winds blow.

I can't see I-810 in Beaumont. Maybe I-910 down to Port Arthur (and even up to Rose Hill Acres).

I could definitely see TX-130 becoming I-235.

If El Paso was ever going to get an I-210 route, I figured it would be on Loop-375. An I-210 route couldn't run into I-10 at both ends without the Woodrow Bean Transmountain Road getting some upgrades to be fully limited access. Such a thing would likely eliminate those scenic overlook pull-overs on the route. If I-110 had been extended up the Patriot Freeway to the North side of El Paso then an I-210 would still be do-able.

Midland-Odessa, Abilene, Killeen-Fort Hood, Corpus Christi, McAllen, Laredo, Lubbock and Amarillo as well as suburbs of the bigger cities all have numerous possibilities for 3-digit routes stemming from various 2-digit (or single digit) parent Interstate highways.

[msubulldog]

IMHO there is a better chance of the New Jersey Turnpike's southern leg becoming an I-x95 than there is of TX 130 becoming and I-x35.

[ethanhopkin14]

I have seen that memo with the reserved interstate numbers on it. I so hope it is not fiction.  I want Toll 45 in Austin to be Interstate 235 and Toll 130 to be Interstate 435 from south of San Antonio following an upgrade of Loop. 1604 to Interstate 10, then cosigning with I-10 to Seguin then follow Toll 130 the whole way, cosign with Interstate 35 for just a second then follow the current SH 195 into Killeen to service Ft. Hood.