Re: AZ Loop 303 Mileposts: You so crazy!!
Ralph Herman
(in article
<e5f5ec05-d505-4634...@34g2000pru.googlegroups.com>):
> I was in town last weekend and had a chance to drive the new section
> of Loop 303. The AZ Repugnant stated that the "new stretch of freeway"
> was open, an idea that I scoffed at. While it is obviously not a
> freeway by any means, I was surprised by how close it was - there were
> a few traffic interchanges - maybe 3? - and a couple more "no bridge"
> traffic interchanges (meaning the main highway follows what will
> become the off ramp/on ramp for the traffic interchange).
>
> The last time I drove loop 303, the mile posts were as expected - near
> I-10 it started at 0, and then 1, and so on. However the traffic
> interchanges, such as Lake Pleasant Rd, were numbered like 138 (or
> something like that). "Oh, neat," I thought. "These must continue from
> the intersection point of loop 303 and I-10."
>
> This makes sense, and I was wondering how they would handle the
> numbering, since the southern terminus isn't defined yet. Per standard
> ADOT protocol, it would have exit 1 at McDowell or Thomas or something
> like that. But then you would have negative exit numbers for when the
> Loop 303 is built on the south side of I-10.
>
> What I figured they would do is "reverse" number it, a-la US 93 and
> I-19 -- make MP 0 at I-17/Loop 303 interchange and increase that way.
> This would make sense because we know that I-17 will be the terminus,
> at least in our lifetimes.
>
> Anyway, long story short, I get to I-10 and I realize the mile posts
> still don't match up as I thought they would. That knocked my ego
> down, but I emailed ADOT asking where the mile post numbers came from.
>
> Turns out that it's the number of linear miles from the border - since
> Loop 303 is "east-west" (I guess) it's from the CA/AZ border. I guess
> in linear miles?
>
> Either way its weird. I don't know if this is the new standard or not.
> I hope not;
ADOT is inconsistant in metro Phoenix where a branching route would continue
the milepost numbering of its original host. Loops 101 and 202 start at
zero, as does AZ 51.
Loops 101 and 202 are partial loops, but IMO LOOP 303 is really a bypass
route, since it connects I-10 and I-17 within the NW quadrant or metro
Phoenix.
Loop 303 seems to follow mileposts continuing from I-10.... where else would
the numbers come from?
The newly opened section of Loop 303 reminds me of the Las Vegas Beltway (CR
215).... ADOT seems to not want to build bridge structures on the mainline
until the local cross roads warrant a grade separation.
When the City of Phoenix built AZ 51 (then Squaw Peak Pkwy) between I-10 and
Glendale Ave, they built the overpasses after the mainline was open, and used
the exit ramps for through traffic on AZ 51 at McDowell, Thomas and Indian
School Roads.
Ralph