Dallas: I-345

[BJ59]

Would it have been better if Interstate 345 had been constructed as a depressed freeway to begin with? After all, US 75 north of TX Spur 366 is a depressed freeway up to Exit 6.

US 75 wasn't initially built as a depressed freeway. By the time US 75 was reconstructed into its current configuration in the 90's, the elevated I-345 Expressway had already been there for 20+ years.

[bwana39]

The new surface street bridges over the new trenched highway will have far more sunlight. Sight lines will be far better for both vehicles and pedestrians. The new sidewalks will be wider and more modern in design. I don't know if TX DOT or Dallas city officials are planning any aesthetic enhancements to the bridges, such as adding any green landscaping or structures to hide the depressed freeway from view. Ultimately the end result is going to look a hell of a lot better and may do more to invigorate the Deep Ellum neighborhood.

I will practically guarantee ALLthe existing buildings in Deep Ellum will be torn down and replaced within ten years of the freeway replacement.

I pointed out the sidewalks would have to be replaced to modernize what is there.

The noise barriers (11' tall) will box in the surface level crossings to rival if not exceed the current dark / dank environs.

The first twenty years of SS-366 before the caps it was pretty foreboding. The elevated portion on the western end was  far more open and inviting than the recessed. Oh yes and the I-30 canyon is really pedestrian friendly and walkable. How much foot traffic crosses US-75 except around SMU?

[Road Hog]

Please forgive my ignorance, but why is this called I-345, and not I-45? This is not a spur off a 2DI -- it is a continuation.

Also, US-75 should be converted to I-45 atleast through McKinney, if not to the OK state line (making it a true "interstate").

Back in the 1960's the thought was that I-45 would follow I-30 to TX-114 to US-287 and US-287 to at least I-44 or perhaps even I-40 in Amarillo. In the 2020's we see I-345 clearly as a continuation of I-45, at he time it was just a spur bridging I-30 ( the then and current technical end of I-45) to the freeway portion of Central Expressway (US-75) north of downtown Dallas.

Not disparaging what you said in the least, because things were different in the 1960s, much less the 1980s or 1990s.

But US 75 has been a complete freeway in Texas up to the Red River since the 1990s and is a logical (and frankly easy) extension of I-45. Improvements have been painfully slow but incremental and it's come into fruition in the Sherman-Denison area.

TxDO'H has drug its feet on US 287 from the get-go and has forfeited its claim on 287 as an I-45 future route. 287 from Ennis to Amarillo (and north) is deserving of its own 2di status.

[The Ghostbuster]

An Interstate 32 designation has been suggested for the US 287 corridor if it were ever upgraded to Interstate Standards. Whether or not that will ever come into fruition is anyone's guess.

[74/171FAN]

I received an email noting that the next public meetings for I-345 will be later this month.

The I-345 Connects public hearing materials will be available starting at 5 p.m. on Tuesday, April 22.

To view the public meeting materials, click HERE

[05danper42842]

An Interstate 32 designation has been suggested for the US 287 corridor if it were ever upgraded to Interstate Standards. Whether or not that will ever come into fruition is anyone's guess.

There are plans and meetings in place for the future of US 287 and possible Interstate designations along the corridor such as near Beaumont Texas and DFW.

[Bobby5280]

A DFW-Beaumont Interstate isn't the thing along US-287 most urgently needed. Fort Worth-Amarillo should be the top priority, starting with the segment from Fort Worth thru Decatur. An Interstate from Dallas to Beaumont would mostly be a duplication of I-45 efforts.

[bwana39]

A DFW-Beaumont Interstate isn't the thing along US-287 most urgently needed. Fort Worth-Amarillo should be the top priority, starting with the segment from Fort Worth thru Decatur. An Interstate from Dallas to Beaumont would mostly be a duplication of I-45 efforts.

Freeway grade at least. It should go from Amarillo to Ennis. The Fort Worth to Ennis part is seemingly in the works.

[Bobby5280]

Yeah, they're slowly chipping away at upgrading the US-287 corridor between I-20 and I-45. I don't expect much more to happen with the non-freeway 4-lane zones around Midlothian and Waxahachie until the big I-20/I-820/US-287 interchange project is completed.

[TXtoNJ]

Please forgive my ignorance, but why is this called I-345, and not I-45? This is not a spur off a 2DI -- it is a continuation.

Also, US-75 should be converted to I-45 atleast through McKinney, if not to the OK state line (making it a true "interstate").

Until the replacement discussions only the MOST ardent road geek knew anything about I-345. It was labeled as US-75 or as To I-45 SB and as to US-75 NB. There still are no I-345 signs. 

Back in the 1960's the thought was that I-45 would follow I-30 to TX-114 to US-287 and US-287 to at least I-44 or perhaps even I-40 in Amarillo. In the 2020's we see I-345 clearly as a continuation of I-45, at he time it was just a spur bridging I-30 ( the then and current technical end of I-45) to the freeway portion of Central Expressway (US-75) north of downtown Dallas.

Why the hidden I-345 designation. Back then, there were funds designated for INTERSTATE highway funding exclusively. As an Interstate funded highway, it had to have an Interstate Highway number. so it was technically I-345 even though there was no marking whatsoever. It was marked as (only) US-75 to avoid any confusion as there was at that point a US-75 concurrency for the entirety of I-45.

There was also a preference that all the 2 digit interstates begin and end at another interstate. This has not come to pass, but in the 1960's it was the goal

I had never heard that before, but it makes a lot more sense than concepts that go up 75. Especially if the concept were a NORAD-Pantex-Sheppard AFB-Lockheed-NASA/Ellington/Port of Houston route that became obviated once bombers were phased out in favor of ICBMs in the late '60s.

[The Ghostbuster]

In some parallels in the history of the Interstate System, believe the segment of Interstate 79 north of Interstate 90 northward into Erie was originally to have been numbered Interstate 179: https://www.pahighways.com/interstates/pdi.html#I179. The Interstate 72 extension along US 36 west of Springfield, IL was originally approved in 1991 as Interstate 172: https://www.aaroads.com/interstate-guide/i-072/#history. That would have been confusing, so it was renumbered to a more logical extension of Interstate 72, and the 172 designation was shifted to the 19-mile freeway segment of IL 336. Also, when Interstate 26 was originally extended north from Asheville, NC in 2003, the remainder of Interstate 181 was originally to be renumbered Interstate 126. However, it became part of Interstate 26 in 2007, as it should have been to begin with.

[MaxConcrete]

I reviewed the new schematic presented at the April meeting. There are substantial design changes between the new April 2025 schematic and the prior March 2024 schematic, all for a much better design.

March 2024 schematic
April 2025 schematic

In the northbound direction, there is now a long, grade-separated (freeway-level) exit ramp from I-30 to Elm Street.

Cesar Chavez is no longer above the main lanes. It is integrated into the frontage roads north of the freeway intersection.

The intersections above the main lanes in the area from Live Oak to Hawkins are gone. These are now done with the frontage roads.

There is now a northbound frontage road (one lane) from Pacific to north of Swiss, where it joins the new frontage road formed by the northbound lanes of Cesar Chavez.

The strange connector street on top of the freeway from Commerce to Main is gone. This connector is shifted west of the freeway, and now extends from Commerce to Elm.

Connection ramp positions are shifted at I-30.

The I-45 main lanes south of I-30 are now in a trench under Hickory, Dawson and Louise Streets. (Currently the freeway is elevated, and the 2024 plan was elevated.)

The connection ramp from northbound I-345 to westbound Woodall Rodgers is now fully replaced, instead of being about half replaced.

Allen Street is brought under Woodall Rodgers, one lane only.