Sub-problem 2a: What types of analysis should be conducted on the I-87/Alternate Route 7 interchange?

Let's first list the ramp junctions present in the interchange. From Exhibit 4-19, we can see there are a total of sixteen ramps in our current study area:

1. westbound Alternate Route 7 exit ramp to I-87 northbound

2. westbound Alternate Route 7 exit ramp to U.S. 9

3. westbound Alternate Route 7 entrance ramp from U.S. 9

4. eastbound Alternate Route 7 entrance ramp from I-87 northbound

5. eastbound Alternate Route 7 exit ramp to U.S. 9

6. eastbound Alternate Route 7 entrance ramp from Alternate Route 7

7. southbound I-87 exit ramp to frontage road

8. southbound I-87 frontage road exit ramp to Alternate Route 7

9. southbound I-87 frontage road entrance ramp from Alternate Route 7

10. southbound I-87 frontage road exit to I-87 southbound mainline

11. southbound I-87 entrance ramp from southbound I-87 frontage road

12. northbound I-87 entrance ramp from State Route 2 and 7

13. northbound I-87 exit ramp to eastbound Alternate Route 7

14. northbound I-87 entrance ramp from westbound Alternate Route 7

15. entrance ramp on I-87 entrance ramp from U.S. 9

16. entrance ramp from U.S. 9 to westbound Alternate Route 7 ramp

However, only three of the locations represent true freeway merge or diverge points:

1. westbound Alternate Route 7 exit ramp to I-87 northbound (including both a diverge point from Alternate Route 7 and a merge point onto I-87)

2. eastbound Alternate Route 7 on-ramp from U.S. 9 (this is a merge point)

3. southbound I-87 entrance ramp from southbound I-87 frontage road (this is also a merge point)