Dot Urbanism

[Image: From Nick Foster's "Hidden Signals" project].

Intrigued by the colorful dots he found spray-painted on the streets of San Francisco, always near drains, Nick Foster began photographing them.

[Images: From Nick Foster's "Hidden Signals" project].

He soon learned that these marks are not some emerging genre of street art—at least not intentionally—but are, in fact, quasi-Pynchonian signals left behind by the San Francisco Mosquito Abatement Courier Team, or SFMAC.

Formed in 2005 following the rapid increase of West Nile Virus in California, this band of pest controllers cycles around San Francisco dispatching sachets of Vectolex into the drains to kill the little biters before they breed. After each drain is treated, the courier sprays a little dot of paint to mark it as completed—this season’s color is blue.

Like full-spectrum hieroglyphs, these spray-painted dots are "infrastructural forensic evidence," in Foster's words, marking the ritualistic elimination of insects from urban space.