The Facebook Cyclists are Drivers group carries a report of a cyclist who was rear-ended by a motorist who was blinded by the setting sun. And, here’s an urban planning issue I bet that you haven’t heard about (unless you have read my Facebook comment on that report). The solution to this problem is, well, blindingly clear, but also, completely overlooked.
Why do street grids have to go north-south and east-west, guaranteeing that the east-west streets will have blinding sun for a week or two, twice a year, early morning and evening peak commute time, and that the south side of those streets will only get sun in the late spring and early summer, early and late in the day?
If the street grids go northeast-southwest and southwest-northeast, then both sides of every street get sunlight every day of the year, and are more conducive to snow melting and plantings thriving. There is never blinding sun along any street (though there can be when turning at intersections — this issue, to be sure, deserves further study).
This approach works except at far northern and southern latitudes, where the sun rises and sets far north or south of the east-west line in midsummer and midwinter.
One city which in fact has a northeast-southwest and northwest-southeast street grid is Montreal, because the long axis of the Montreal island runs northeast-southwest. That’s one more reason, though not the main one, to discredit the Lusk et al. study of Montreal bikeways 😉
In the USA, the east-west-north-south blinding glare problem was given a major boost by the Homestead Act of 1862, which laid out most of the Midwest and Great Plans, both urban and rural, as far west as the Rocky mountains, in north-south-east-west grids.
The late Prof. John Finley Scott, a staunch advocate of integrated cycling, proposed “wrecking ball therapy” as a way to cure the problems with aging urban infrastructure, and perhaps this is an improvement to keep in mind in that context.
Interesting idea. I lived in Montreal for five years (and cycled there) and can’t recall having a problem with the sun there (although it was more than 30 years ago).
One non-transportation advantage of north-south and east-west streets is that houses and buildings with the long axis east-west receive more solar radiation through windows in the winter and less in the summer. The orientation of east-west buildings is also better for solar PV cells and solar hot-water systems.
Ah, then we need buildings on the northeast or northwest side of streets to have their street side at 45 degrees to the street, making room for bicycle parking. On the other side of the street, the back sides of the buildings. So there would be a lot of triangular spaces. Hey if modern computer-aided architecture can come up with this, what I propose should be easy by comparison.
If glare were the only consideration, then one could track where the sun is setting and rising when it rises and sets at rush hour, which for us at least is about now. But I suspect its a little late for such urban renewal efforts, short of an asteroid impact.
One thing cyclists can be taught to do is pay attention to their shadow. When one’s shadow is long and pointed towards the motorist sitting at a stop sign as you ride by, you know he/she is impaired by the glare. Or, if one’s shadow is cast long and directly behind you, you know overtaking motorists are impaired. One can try to compensate. There is one after-work ride I don’t do this time of year because of that situation.
In my neighborhood, the streets run pretty close to your recommended angle. But in some months, traveling SE or NW points you almost directly into the sun. This is at a latitude of about 37 degrees.