Quote:
Originally Posted by Hatman
Perhaps you have some insight, I-215, if such a thing is possible under current freeway design standards?
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I have seen a
freeway-to-garage ramp system done before off the SR-400 freeway north of Atlanta.
Two characteristics are different with this site, versus the one you diagram above:
* The Atlanta garage ramps are only grabbing
one set of movements (to/from the north) to capture inbound traffic only.
* Your proposal tries to grab from multiple directions.
* The Atlanta garage ramps are
spaced fairly far from adjacent interchanges.
* Your proposal has zero spacing. This requires a complex of flyover ramps right at the I-80/400 South complex, which would be very expensive and technically challenging to do.
* The Atlanta garage ramps wrap around to the back side (relative to the freeway, opposite the rail station) giving adequate slowing/stopping distance.
* Your proposed site would mean ramps would be impeding with pedestrian access to the train station.
Could it happen? Yes, I think a design like this
could happen, but is extremely unlikely due to cost and potential operational impact to the existing interchange. More than likely the garage would have ramps that connect to 400 South, rather than to the freeway directly. This napkin sketch shows how to accommodate reasonable access without any new ramps at all:
It's worth asking a bigger question: Would money be better spent expanding parking options at suburban rail stops rather than at one big one? This garage will likely supplement (rather than replace) existing parking spaces downtown. Each new space attracts new traffic on I-15. With the investment we have already made on Frontrunner and TRAX, I believe we are better served to end the vehicle leg of trips as far away into the suburbs as we can and use rail to bring people into intermodal.
Ideally, I'd kind of like to see most of the downtown parking disappear entirely. In the future, people park at their nearest TRAX station and ride the rest of the way in. That would take a lot of pressure off the I-15 corridor through SLC proper.