Back with another update. I think you'll enjoy this one. Yes, the MIS has arrived--if you've been following the RHW Development thread [link], things have been coming along on it quite nicely, with a lot of development over the past week or so.
Well, at any rate, here's one of the projects slated for the Bob Dylan Freeway (Highway 61 )--the Ferrum Road interchange, which is located on the north side of Argentum, in the Tarentum neighborhood. Ferrum Road is particularly critical to North Argentum, providing freeway access to one of several high-tech districts in town, and it will also provide a crucial link to the new Argentum International Airport upon completion.
Construction has already begun in this shot. Access to the freeway is currently through a rather unsafe at-grade intersection. The pre-existing 2-lane overpass is still in place, so that traffic traveling past the highway on Ferrum Road can do so without dealing with the at-grade crossing.
The overpass demolished, with equipment in place to rebuild the overpass
A couple of trees are in the way of the ROW for the ramps to and from northbound Highway 61. However, the environmental impact is still minimal, a major goal of these new improvement projects--the giant stands of redwoods to the south are entirely undisturbed. As you can see, a new 4-lane overpass has been built.
The basic design here for the ramps is a Parclo AB or Folded Diamond, chosen for environmental reasons. (Also, a rather common interchange design here in Oregon.)
The ramps to/from the Southbound lanes
The ramps to/from the Northbound lanes
The interchange will probably still get a little tweaking here, just to improve flow a little more.