The vacant block effect

Vacancy in Philadelphia is geographically extreme. About 8,297 vacant buildings are catalogued citywide, but the load isn't spread evenly across the 50 ZIP codes — it concentrates in a handful in North, West, and South Philadelphia. 19134 carries more than any other.

Next: where intervention has landed. The map shading will shift to fern — same geography, new metric.

The Pennsylvania Horticultural Society's LandCare program turns vacant parcels into clean, fenced, planted lots. Over 0 parcels have been stabilized across the city. Notice the shading: the LandCare map doesn't mirror the vacancy map. Some high-vacancy ZIPs see heavy intervention; others see relatively little.

Now switch lenses to what residents are reporting — the 311 calls about dumping and graffiti. The map shifts to fluoro.

Since 2023-01-01, residents filed roughly 106,513 311 reports about illegal dumping or graffiti — the visible street-level signals of disinvestment. Stack this against the vacancy and LandCare maps and a comparison sharpens.

The next beat splits the most-vacant ZIPs into two groups: the half where LandCare has landed most heavily relative to vacancy, and the half where it hasn't.

The brick map shows blight burden per intervention: 311 reports divided by LandCare sites in each high-vacancy ZIP. A high score reads as "lots of complaints, not much stabilization landing here." A low score reads as "stabilization is keeping pace with the load." The story this measure tells is not which neighborhoods are worst — it's where the gap between need and intervention is widest.

Stabilization is not a synonym for renewal, and 311 calls are not a clean measurement of neighborhood condition. But the ledger below shows the texture: which high-vacancy ZIPs the LandCare program reaches, and which it doesn't.