I’m going to make this a quick one. Here is part of a pathfinder survey from 1936 of alleys in DC. I picked out some Shaw related alleys. It says were the alleys are, as in which city square they are located, how many alley dwellings there were and how many of those were occupied by people. The point was to kick people out of their alley homes.
Source: National Archives and Records Admin. Washington, DC. Record Group 302, entry 3, maybe file Pathfinder Survey (1936).