03 July 2008

The lost highway!

Actually it's not all that lost, but anyway...today I moseyed on up to the North and snapped a few feeble pictures of Louisiana's oldest interchange!

The Scenic Highway/Airline Highway cloverleaf dates to 1940 when Airline Highway was constructed through the area, as the approach to the "old" Mississippi River bridge (which carries US 190).  I can't think of an interchange in this state which is older, so this is Louisiana's very first grade separated junction ever constructed, as far as I know.  

This interchange constitutes the northern end of the US 61/190 concurrency in the Capital area. US 190 approaches from the west on Airline, US 61 approaches from the north on Scenic, and they combine and venture off to the east, eventually turning southeast as they bypass the city center. Scenic Highway continues to the south into the city as Business US 61/190. This interchange thus comprises the business route's northern terminus (incidentially, its southern end is also at a cloverleaf).

This is a very old, very substandard junction.  Here is an aerial image from Google Earth (north is at the top):



(Scenic runs north-south at an angle, Airline east-west.)

As you can see, the ramps (especially the inner loops) are rather hairpin in nature, due to the constricted design of the interchange.  (Yes, this vicinity was developed in 1940 - more developed than it is now, in fact, as you can see that urban prairie grass grows rampant here now.)  

My suggestion is to convert this into a standard diamond interchange, and dispose of the nasty 15 MPH loop ramps.  The junction footprint is more suited to a diamond, in any case, and the traffic counts are low enough to justify such a modification.  This is no longer a particularly important junction, as the massive I-110 stack (one of only a handful in the state) lies just to the east and currently handles the bulk of the traffic movements which this cloverleaf formerly served.

(Lots of interchanges in this area.)

Here are some ground level images!



Looking south on Scenic toward the interchange.  The ancient first generation bridge guardrail gives this away as a really old grade separation.

You may notice the lack of decent signage here, which is somewhat typical for Louisiana.  There used to be a really old, barely legible sign with control cities on the overpass: something like

PORT ALLEN
OPELOUSAS    ->

I seem to have missed something. It was here last time I checked. Where did it go?



Southbound on Scenic, slowing to a crawl as I prepare to navigate the treacherous loop ramp to follow US 61 south.  As I mentioned above, the ramps are rather hairpin.

The US 61/190 shields, BTW, are on a single sign.



Proceeding up the loop ramp to meet Airline Highway.  A "By-Pass" US 61 shield is posted on the ramp, as this is the way to follow mainline US 61 southbound.  The By-Pass banner is ironic, as this has not been officially "By-Pass" US 61 since the mid-1960s.  And yet this sign is relatively new...

The road on the left is the offramp from Airline to Scenic.  If you point your peepers to the upper right, you will notice the light poles.  Those are located in the median of Airline Highway.  The grass on the rise to the right ends at the curb of that road.  Gonna be a pretty sharp turn ahead...

I would have snapped a picture of the "1940" stamp date on the bridge abutment, but I don't do photography well in high-speed traffic (Airline is essentially a freeway at this location).  So oh well.

2 comments:

US 71 said...

I think I was through there a couple years back. Do the the bridge supports have "US 61" imprinted in the concrete? I have some photos *somewhere*, I think. ;)

Urban Prairie Schooner said...

Indeed it does; I forgot to mention that. It is stamped in the center support, and you can plainly see it while driving on Scenic Highway.