NPR has an article up about Diverging Diamonds.
While the Missouri Department of transportation talks about how this is great for vehicles, it is also great for pedestrians:
- all crossings can be signalled for long crossing times because pedestrians are walking with the main flow of traffic — so lots of time for moms with kids to get across.
- the center island can be double the normal width — the 2 sidewalks on the edge of the bridge are combined to one double width sidewalk.
- planter boxes or fencing on the perimeter of the center island can help reassure moms (and dads) that the 3-year old is not going to escape into traffic.
- NO worries about people turning into pedestrians – all traffic is going the same direction as pedestrians — except for the initial right turn on to the freeway.
- the right turn on to the freeway can easily be signaled and no right-turn on red allowed.
- the gray areas at the end of the bridge also provide nice big areas.
- Really, really easy to get across Missouri 13. It is now trivial to get do a diagonal crossing so that 44 and 13 are both crossed.
h/t to AdamHertz for pointing the NPR article out.
There’s also another attraction to a central walkway. Most highway bridges in my area have elaborate fences along the sides to prevent vandals from throwing objects into the freeway below. Moving the sidewalk to the middle seems a good deterrent. Anything that made them feel less like prison balconies would be an improvement!