For a brief, shining moment, San Francisco was clean. The arrival of world leaders for a high-profile summit earlier this month prompted the city to jump into action, hosing down its streets and sprucing up neglected downtown neighbourhoods. The change was dramatic. It was also shortlived.

San Francisco is a city of stains. The sunshine glitters and the waters of the Bay sparkle but at street level, the centre is noticeably filthy. Some of these stains are palatable. Warm weather means fruit trees grow along the roads, dropping cherry plums and carob pods that get squashed underfoot. But most are man-made. Every year, the SF Department of Public Works receives thousands of reports of human faeces on its streets. 

Understandably, this is a subject that preoccupies locals. Not long after I moved here, a friend sent me an unusual guide to SF neighbourhoods known as the SF poop map. Created by a non-profit called Open The Books, the online map claims to show the location of every one of these reports made between 2011 and 2019. Zoom out and dots cover almost the entire city. Only a sliver of Pacific beach and the hills of Presidio park are clear.