Photo by PoPville flickr user angela n.
Looks like it’s from the DC Department of Transformation (“A tactical urbanist org that believes that cities should be designed for people, not cars. Reclaim space for community use, accessibility, and sustainability.”):
“We have our second Pandemic Protected Sidewalk! This one is at 17th and Church NW.”
— DC Department of Transformation (@DCDOTRA) April 8, 2020