[Talk-us] Update on potential highway classification reform

[Adam Franco]

On Wed, May 19, 2021 at 2:02 PM Brian M. Sperlongano <zelonewolf at gmail.com>
wrote:

> Anthony - thanks for this fascinating bit of Interstate trivia.  I was
> totally unaware about these cases.  I found a comprehensive list of
> exceptions on Wikipedia, and there's far more than I realized:
>
>
> https://en.wikipedia.org/wiki/List_of_gaps_in_Interstate_Highways#At-grade_intersections
>
> Would we be okay with something like:
> - Downgrading a section of Interstate to trunk for all cases on the "Major
> at-grade intersections" and "Other at-grade intersections" list
>
This feels right and is very much in keeping with the "prioritize
connectivity" theme of reforming trunk usage.


> - Retaining motorway for all cases on the "minor at-grade intersections",
> "Undivided and narrow freeways", and "movable bridges" list
>

"minor at-grade intersections": I think these generally don't warrant a
downgrade from motorway. All of the ones I've encountered out west are
extremely low usage and don't appreciably change the character or usage of
the roadway much more than an emergency pull-off would. These are generally
present only in extremely remote areas and see so little traffic that
downgrading would be more silly than not.

"movable bridges": I would be ok with keeping these segments as motorway as
long as the bridge-opening frequency is low enough that the motorway
character and expectation of road users having priority isn't normally
violated. At the extreme end, a drawbridge that is only operated in
extremely rare circumstances (say normally once a year for
testing/maintenance) would not impact road users enough to warrant
downgrading. One that operates multiple times per day on the other hand
probably would warrant downgrading as there should be the expectation of
waiting on marine traffic. These may need to be taken case by case based on
operational frequency.

"Undivided and narrow freeways": I'm less convinced that these should stay
motorway just because they are signed as part of the interstate system. By
definition these don't meet *all* of the motorway physical characteristics
and road users *should* expect to go more slowly in these constricted
locations, so downgrading these to trunk feels more logically consistent
with the classification scheme for non-interstate highways.
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