When is urban planning on-topic on engineering?

Question

There exists an Urban Planning proposal on Area51. Many proposed questions are about traffic planning. For example:

Do pedestrian crossings with countdown signals reduce the number of fatalities from auto collisions?

What makes Swindon's Magic Roundabout work so well?

In cities that have significantly reduced car traffic in city centres, how has this affected commerce in centre and periphery?

How can you decrease jam-avoiding traffic in the smaller roads.

How to diminish noise from high-traffic roads?

Engineering SE has a highway-engineering tag, with the topic defined as:

Highway engineering covers the design of highways, in particular: layout (vertical and horizontal), surfacing design and drainage.

and some popular questions:

• What are the pros and cons of a traffic circle versus a traffic light intersection?
• Has a specific type of alternative intersection been shown to reduce congestion & accidents?

To me, those proposed Urban Planning questions appear very similar in style to the linked questions already on Urban Planning and apparently condoned by the community.

Under what circumstances are Urban Planning questions on-topic on Engineering?

For example, are the questions I quoted above on-topic on Engineering?

Answer 1

From the questions that you listed, all of the traffic planning topics would certainly be acceptable here.

There is a separation of Urban Planning and Engineering though. As an example, at the college that I went to, traffic engineering (road design, safety, modeling, etc.) was in the civil engineering department of the engineering college. There was a separate urban planning department in the liberal arts college.

I took some of the Urban Planning courses and they were more policy and public opinion based (verging on political science at times).

In summary, the degree of overlap will be based on the questions that are asked, but there certainly is a lot of possible overlap.

Answer 2

Skimming over the proposal, it looks like many of those questions would be on-topic for Engineering.

I'll add a cautionary note that some of the questions appear to be overly broad. But given that the proposal is in the discussion phase, I think that's understandable. Area51 proposed questions don't always directly align well with SE's Q&A guidelines.

And I'll also note that there isn't a perfect overlap, and some questions aren't a good fit. For instance, In cities that have significantly reduced car traffic in city centres, how has this affected commerce in centre and periphery? probably wouldn't work well here on Engineering.