The intersection of Polk Street and Broadway. Photo courtesy of SBT4NOW.

Guest post by Aleksey Bilogur

Every urbanite knows how important clean streets are to the attractiveness and viability of a neighborhood. Clean streets mean walkable streets, walkable streets mean busy streets, and busy streets mean prosperous neighborhoods.

Nobody knows this better than the founders of rubbish, Emin Israfil and Elena Guberman. Armed with trash bags and eye-catching smart litter grabbers, aka “rubbish beams”, they have picked up an impressive 130,000 individual of litter over a year of consistent street cleanings in San Francisco. All the while, the rubbishers collected data on what type of litter was picked up, where, and when.

This article is the first-ever analysis of this unique and expansive dataset. We will slice and dice the street pickups by location, type, and time - learning how our habits as pedestrians and residents of our communities affect our urban environment in the process.

Setting the scene

Rubbish runs are conducted on four blocks of Polk Street, between Filbert and Broadway, in the Russian Hill neighborhood of San Francisco. During each rubbish run the volunteer rubbishers aim to clean up every piece of litter that is on the ground, including litter clogging gutters and drains.

Polk Street is most residential at its northern end but becomes more commercial as you go further south. Commercial areas are more trash-laden than residential ones, due to increased foot traffic, and Polk Street is no exception. If we plot the average number of pieces of litter on the street per block per day, we see just how strong this effect is:

Higher numbers indicate more litter. The centerline represents Polk Street, San Francisco.

In just a couple of blocks, litter pieces of litter jump from just 16 items per day to an incredible 90 items per day. Put another way, the cleanest block on Polk Street is littered on 5,800 times per year; the dirtiest, 32,000 times per year.

The block of Polk Street between Broadway and Vallejo is more than twice as dirty as the block directly across the street (90 pickups per day on the west side, just 37 per day on the east side) even though both blocks are 100% commercial.

What’s causing this increase in litter? Litter correlates to both business location and type. Anecdotally, businesses that have more to go items plus foot traffic contribute more litter overall. The west side of Polk Street has all of the street’s pizza shops and bars, plus a nightclub, whilst the east side of Polk Street has pharmacies and hardware stores and a bookstore. And while the two sides share the neighborhood’s restaurants and coffee shops, the difference between a sidewalk abutting Rouge Nightclub and one abutting Walgreens is easy to see: