User:Ldriveskier/Contraflow Configuration

(writing this to be able to be linked as a standalone page... can always cut/paste later. -AD)

Crossover Reconfigurations are necessary when normal one-way traffic on a divided road is diverted across the median on a divided road, and then runs in a contraflow manner respective to the traffic direction on that side of the median.

Crossover reconfigurations and new traffic patterns can be quite varied depending on construction parameters; therefore, editors should consult their respective Large Area Managers or State Managers before beginning the process for a scheduled reconfiguration involving crossovers.

Draw Contraflow Segment

1. Draw a new segment spanning the length of the new crossover section. This new segment should remain unconnected from any existing segments at this point.
2. Place this segment adjacent to the existing segment that this new segment will serve as a contraflow lane against.
   • Adjust the geometry nodes on the new segment so that the contraflow segments are parallel.
3. Set appropriate attributes for the new contraflow segment.
   1. Road type (Freeway / Major Highway / etc)
   2. Direction: One Way (A->B or B->A, depending on how segment was drawn)
   3. Speed Limit: For contraflow sections, note that there may be different speed limits based on direction of travel through the reconfigured area.
   4. Elevation: Match the elevation of the newly drawn segment to the contraflow segment being mirrored. (may need to cut the newly drawn segment for elevation changes, watch especially around exits and underpasses/overpasses)

Connect Contraflow to Existing Segments

Start by connecting the contraflow segment at the end of the crossover. Follow the entrance ramp geometry guidance for drawing the merge angle.

At beginning of the crossover, connect the segment following exit ramp geometry guidance.

• Consider that there will likely be a SWL separating lanes before the actual lane crosses over into oncoming lanes.

Consider adding wayfinders to match signage or provide guidance. For example,

• I-80 W only / Thru traffic
• I-80 W / to exit 187 / I-480 / SR-14
• Note: consider adding "All Exits" if there is more than one exit that is only available from one side
• Note: be sure to remove alt-names to avoid BC
• Note: if setting this up as part of a scheduled reconfiguration, make sure the wayfinder for the existing lanes stays as BC until the crossover is active.

Note: I prefer to draw the whole thing first (before even asking for a downlock), attach the end second, then attach the beginning. If I get pulled away in the middle, I'd rather have a random segment laying around that isn't attached to anything important.

(add some guidance up front pointing to the scheduled reconfigurations page? Or are we going to incorporate this page into that one or into the interchange style guide as Kartografer suggested?)