I was inspired to make this map thanks to Greater Greater Washington's coverage of the 2016 DC zoning code. After reading about the possibility of corner stores in DC I had fond memories of the tiny grocery that was right around the corner from my home in Brooklyn. Even though I barely cook, I was amazed at the efficiency of that store. It seemed to have everything you needed and nothing else, including free space.
To figure out where corner stores might show up I dug around until I found chapter 254 of subtitle U of the 2016 DC Zoning Code. Section 6 of which has seven rules.
Several (a,b,c,g,e) of the rules are straightforward geographic considerations. (i.e.) must be in this type of zone, can't be within 750ft of that type of zone. Those were easily symbolized on the map by green dots at intersections that meet the requirements, and red buffers for restrictions. Due to my decision to symbolize the corners themselves, I didn’t have to work through restrictions on the type of building.
But some building restrictions seemed important to convey. Georgetown has stuck with the old law: Only pre-1958 commercial buildings in use in the last 3 years qualify. Those corners are shown as crab mustard yellow. R-3 -13 and -17 zones are little less restrictive: pre-1958 commercial buildings qualify, whether or not, they have been in use recently. Those corners are a tomatillo salsa green. Finally, the rest of the corners are dark green, where the history of the building is not considered. There are a few more restrictions on building types that I could not convey. I suggest anyone starting a corner store check out the regulations for themselves. That said, I feel the map gives a good sense of where new corner stores might show up.
While the zoning changes are a great improvement, several neighborhoods including Petworth, Brentwood and Marshall Heights are stuck with, at best, the corner stores that existed 58 years ago which seems unlikely to be ideal. Though GGW does have an encouraging post about how many of those building do exist.
One regulation was not easy for me to put on a map even though it seems possible:
(a) On a lot that is at the intersection of two (2) generally perpendicular streets;
Since I am new to geography I don’t know how to interpret "generally perpendicular." Someone suggested intersections at angles between 46° and 134°. But I bet that wouldn't pass the smell test. In the end I went along state streets and deleted points at intersections that looked to me not be generally perpendicular. If anyone knows how to apply this rule in a more rigorous way I'd be interested to hear about it.
After placing points on all the intersections in DC an unexpected class of intersections appeared. As far as I can tell, "T" intersections meet all the requirements for corner stores. Several of these can be seen on the map, for example 18th St. and Monroe NW. Personally, I would be happy to shop at a mid block corner store.
While working on regulations (b) and (c), which describe how far corner stores have to be from each other, I figured two interesting things. First, almost no areas currently meet those restrictions. Second, if you turn those regulations on their head you can imagine a vibrant DC corner. By my reading, some corners in DC could have two eating and drinking establishments and two other establishments. This brings to mind a nice little corner where you can get groceries, share a glass of wine with friends, and maybe get a haircut, all in your own neighborhood.
Thanks for taking a look at this. If you have any questions or found an egregious spelling error, feel free to send me an email.