Question about the construction at I-44 and US-169 (Tulsa)

[Scott5114]

A new cloverleaf interchange is going to be built on I-44 in Chickasha for the new US-81 bypass. I think construction on that starts in the next year or two.

It is kind of insane that Oklahoma is still building cloverleaf interchanges in the 21st century.

[BigOkie]

Since it's finished now I thought I'd throw up an updated overhead view (even though this one was before completion it was pretty close; the image is dated Oct 2023).

[sprjus4]

A new cloverleaf interchange is going to be built on I-44 in Chickasha for the new US-81 bypass. I think construction on that starts in the next year or two.

It is kind of insane that Oklahoma is still building cloverleaf interchanges in the 21st century.

A cloverleaf interchange in a low volume, rural area with C/D ramps is acceptable, IMO. North Carolina has built a few in the past decade or two, including near urban areas.

The important piece is the C/D ramps though... without those you're introduce even the smallest amount of conflict when a vehicle entering at 25 mph encounters 75 mph traffic.

[Bobby5280]

I haven't seen a detailed schematic of the US-81 bypass in Chickasha. But I'm pretty sure its interchange with I-44 is not going to include C/D ramps. The interchange should include C/D ramps for the sake of safety. I just don't think ODOT and OTA are going to spend the extra money for such a thing. After all, the US-81 bypass itself is going to be a (mostly) limited access Super-2 in its initial configuration and then expand to a 4-lane divided freeway in the future.

I don't like cloverleaf interchanges, but in semi-rural locations what other kinds of interchanges between two limited access highways could be built? A 4-level directional stack in Chickasha would be quite an extravagance. A pinwheel interchange could be a less expensive option than a stack, but it would still cost quite a lot more to build than a cloverleaf due to all the additional bridges and graded berms needed for the four interior spiral ramps.

[sprjus4]

I haven't seen a detailed schematic of the US-81 bypass in Chickasha. But I'm pretty sure its interchange with I-44 is not going to include C/D ramps. The interchange should include C/D ramps for the sake of safety. I just don't think ODOT and OTA are going to spend the extra money for such a thing. After all, the US-81 bypass itself is going to be a (mostly) limited access Super-2 in its initial configuration and then expand to a 4-lane divided freeway in the future.

I don't like cloverleaf interchanges, but in semi-rural locations what other kinds of interchanges between two limited access highways could be built? A 4-level directional stack in Chickasha would be quite an extravagance. A pinwheel interchange could be a less expensive option than a stack, but it would still cost quite a lot more to build than a cloverleaf due to all the additional bridges and graded berms needed for the four interior spiral ramps.

I did some digging and I found a project page from 2022, and then there was an Access Justification Report on there with signing plans on PDF 34-35. It appears there will be a single exit for both directions, then two individual exits for both I-44 and US-81, which would imply C/D lanes. Other traffic memos also show a split roadway there for both highways.

Project Page: https://oklahoma.gov/odot/progress-and-performance/federal-grant-awards/mpdg-grants/mpdg-2022/grady_county_us-81_realignment.html

Access Justification Report: https://oklahoma.gov/content/dam/ok/en/odot/federal-grants/mpdg/2022/grady-county-us-81-realignment/reports-and-technical-information/Access%20Justification%20Report.pdf

[rte66man]

I haven't seen a detailed schematic of the US-81 bypass in Chickasha. But I'm pretty sure its interchange with I-44 is not going to include C/D ramps. The interchange should include C/D ramps for the sake of safety. I just don't think ODOT and OTA are going to spend the extra money for such a thing. After all, the US-81 bypass itself is going to be a (mostly) limited access Super-2 in its initial configuration and then expand to a 4-lane divided freeway in the future.

I don't like cloverleaf interchanges, but in semi-rural locations what other kinds of interchanges between two limited access highways could be built? A 4-level directional stack in Chickasha would be quite an extravagance. A pinwheel interchange could be a less expensive option than a stack, but it would still cost quite a lot more to build than a cloverleaf due to all the additional bridges and graded berms needed for the four interior spiral ramps.

I did some digging and I found a project page from 2022, and then there was an Access Justification Report on there with signing plans on PDF 34-35. It appears there will be a single exit for both directions, then two individual exits for both I-44 and US-81, which would imply C/D lanes. Other traffic memos also show a split roadway there for both highways.

Project Page: https://oklahoma.gov/odot/progress-and-performance/federal-grant-awards/mpdg-grants/mpdg-2022/grady_county_us-81_realignment.html

Access Justification Report: https://oklahoma.gov/content/dam/ok/en/odot/federal-grants/mpdg/2022/grady-county-us-81-realignment/reports-and-technical-information/Access%20Justification%20Report.pdf

Full c/d lanes for both. Access Justification Report p31:

The proposed access is part of the 8.24-mile US-81 project west of Chickasha. It is a cloverleaf full
interchange with collector-distributor roads that accommodate all basic movements needed for the
proposed interchange.

[Bobby5280]

That's a pleasant surprise. The C/D lanes would barrier-separate the slower, weaving traffic using the cloverleaf ramps from the I-44 thru traffic that is going upwards of 80mph or even faster on the main lanes. I wonder if C/D lanes will be built only alongside I-44 or built along both I-44 and the US-81 bypass. I'm guessing probably not for the latter.

It's too bad the cloverleaf interchange at I-44 and the H.E. Bailey Turnpike Extension wasn't built with C/D lanes. It doesn't look like those kinds of lanes could be added into the existing interchange either.

[sprjus4]

That's a pleasant surprise. The C/D lanes would barrier-separate the slower, weaving traffic using the cloverleaf ramps from the I-44 thru traffic that is going upwards of 80mph or even faster on the main lanes. I wonder if C/D lanes will be built only alongside I-44 or built along both I-44 and the US-81 bypass. I'm guessing probably not for the latter.

The signage / schematic plans shows both highways will have C/D roadways.

[bugo]

Cloverleafs are not acceptable in 2024, period.

[Plutonic Panda]

They shouldn't be built at all IMO.

[DJStephens]

C and D roadways make them acceptable in rural locations, where there is land availab le for an expansive interchange.   Believe they were constructed at several locations on the I-269 southern leg of the Memphis loop.   

[CoreySamson]

Now that this ramp has been open for a little while and that I have used it several times, I have to say that this small project paid off big-time. What used to be one of the most dangerous, hectic merges in Tulsa has now become my favorite. I would think that this kind of ramp design could be used to cheaply retrofit loop ramps at problem cloverleaves around the country, honestly.

[DJStephens]

Cheaply.  That's the problem.  Spending a significant fraction of the ideal solution (two flyovers) to build a wonky $20 million ramp.   All part of a trend of design regression and poor decision making.  Also known as a 'throwaway improvement" a lot of those exist in New Mexico and el Paso county.   

[Scott5114]

All part of a trend of design regression and poor decision making.

Calling poor decision making by the government of Oklahoma a mere "trend" is being much kinder to them than they deserve.

[CoreySamson]

Cheaply.  That's the problem.  Spending a significant fraction of the ideal solution (two flyovers) to build a wonky $20 million ramp.  All part of a trend of design regression and poor decision making.  Also known as a 'throwaway improvement" a lot of those exist in New Mexico and el Paso county.   

My counterpoint is that if you can get the job done for much cheaper without sacrificing much else in return, why not do it? Sure, yeah, two flyovers would be nice here, but the new ramp design for this interchange is fundamentally the same for much less money. I feel that flyovers in this location would take up too much space, anyways.

[Bobby5280]

That new ramp from EB I-44 to NB US-169 isn't much of an improvement. It does eliminate the terrible weaving conflict that existed on the NB US-169 bridge over I-44. The new ramp provides a longer "runway" for vehicles coming from WB and EB I-44 to merge onto NB US-169. But now we have a traffic weaving situation with that traffic merging onto US-169 and other vehicles getting off US-169 at the 11th Street South/OK-66 exit.

The new ramp at the I-44/US-169 interchange doesn't offer anything else in terms of improvements -at least not anything that improves travel speed or traffic capacity. The new clover ramp has a 20mph rating. That sucks.

A new direct-connect flyover ramp from EB I-44 to US-169 would have been better. The ramp might have given the apartment complex on the NE corner of the interchange a "haircut". The curve geometry of the WB I-44 to NB US-169 surface ramp is pretty crooked looking. It's a sudden 25mph-rated turn that smooths out farther North. It's obviously done to avoid the apartment buildings. The only good thing in that spot is the additional ramp merge from E 7th Street was eliminated.

[CoreySamson]

That new ramp from EB I-44 to NB US-169 isn't much of an improvement. It does eliminate the terrible weaving conflict that existed on the NB US-169 bride over I-44. The new ramp provides a longer "runway" for vehicles coming from WB and EB I-44 to merge onto NB US-169. But now we have a traffic weaving situation with that traffic merging onto US-169 and other vehicles getting off US-169 at the 11th Street South/OK-66 exit.

How would having a flyover change anything about that merge? That merge is going to exist there regardless of whether the current interchange setup is there or not because the 11th St interchange is so close to the I-44/US 169 interchange (and even then, it's much better than what it used to be before they made it a folded diamond!). I guess ODOT could interweave the ramps similarly to how they did with the I-44/US 77 interchange and NE/W 63rd interchange in OKC if it really became a problem. The point I'm making is that the current ramp configuration coming from I-44 is not the problem here. It's the location of the 11th St interchange. Adding a flyover won't change that.

The new ramp at the I-44/US-169 interchange doesn't offer anything else in terms of improvements -at least not anything that improves travel speed or traffic capacity. The new clover ramp has a 20mph rating. That sucks.

I mean, it's not perfect, but as I've said, it was an inexpensive solution. Oklahoma doesn't have Texas money to throw around at interchanges to make them stacks. In an ideal world, maybe. Even so, I see Oklahoma is actively making improvements to problem areas on its highways, even if those improvements are "cheap". That's a heck of a lot better than what a lot of states are doing.

But I would argue (against your claim) that it does improve travel speed. The old cloverleaf ramp smacked straight into US 169 traffic and had to merge quickly (as I've said before in this thread, that old merge used to be the hairiest merging spot in Tulsa IMO). Now, traffic on the ramp has a lot more time and space to adjust to the speed of the freeway, which makes the merging safer and quicker.

A new direct-connect flyover ramp from EB I-44 to US-169 would have been better. The ramp might have given the apartment complex on the NE corner of the interchange a "haircut". The curve geometry of the WB I-44 to NB US-169 surface ramp is pretty crooked looking. It's a sudden 25mph-rated turn that smooths out farther North. It's obviously done to avoid the apartment buildings. The only good thing in that spot is the additional ramp merge from E 7th Street was eliminated.

Hardly any traffic is using that WB I-44/NB US 169 ramp anyways. Most traffic instead uses the I-244 or 11th St exits from I-44 to make that connection. Honestly, they probably should have removed it, just like they did for the WB I-44/SB US 169 ramp. Not saying it's perfect like it is, but it's not a huge problem.

I would guess you also implicitly admit here that space would be an issue in building a flyover. There is not a lot of space around this interchange to put a flyover in without getting rid of something near the interchange. Flyovers take up either a lot of space horizontally or a lot of space vertically. Since there is not much horizontal space at this interchange to put in a good flyover, you would need more vertical space, which would probably put that merge even closer to the 11st St interchange, which would not be a good thing. So either way, putting in a flyover compromises something.

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All that to say that I think that this ramp is an elegant inexpensive solution to the problem merge the interchange used to have.

[Scott5114]

My counterpoint is that if you can get the job done for much cheaper without sacrificing much else in return, why not do it?

I think the argument that DJStephens is making is something along the lines of "If you can get a 16-ounce soda for $1, and a 12-ounce soda for 99¢, what fool would ever buy the 12-ounce soda?"

[Bobby5280]

The point I'm making is that the current ramp configuration coming from I-44 is not the problem here. It's the location of the 11th St interchange. Adding a flyover won't change that.

A proper flyover ramp from EB I-44 to NB US-169 would have a much higher travel speed than the 20mph limit of the tight clover loop of what ODOT actually built. That same flyover ramp could also span over a new, reconfigured US-169 exit ramp to 11th St S/OK-66 in a pseudo braided fashion. That would eliminate the weaving conflict that now exists with the lower cost solution ODOT built.