Philadelphia's missing shade
Philadelphia lost 5.9% of its tree canopy between 2008 and 2018. The neighborhoods that lost the most green are the same ones with the highest heat vulnerability scores — and the lowest median incomes. A scroll through the compounding geography of heat, trees, and who bears both.
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The vacant block effect
Philadelphia has roughly 8,000 vacant buildings on the city's books and 12,000 parcels stabilized by the PHS LandCare program. They don't sit in the same places — and the 311 dumping and graffiti calls reveal whose blocks the gap leaves behind.
Philadelphia's pothole season
Philadelphia's 311 system files potholes and pavement failures as 'Street Defect' — 167,000 reports and counting. They cluster along high-traffic corridors, spike every late winter as freeze-thaw cycles break the asphalt, and almost always get reported during the morning commute.
Riding the pothole
Most maps show where the street is broken. We wanted to show what the bus rider sees from the platform — and which of SEPTA's ~10,000 Philadelphia stops sit in the middle of the city's heaviest 311 street defect and lighting load.
Philadelphia's missing shade
Philadelphia lost 5.9% of its tree canopy between 2008 and 2018. The neighborhoods that lost the most green are the same ones with the highest heat vulnerability scores — and the lowest median incomes. A scroll through the compounding geography of heat, trees, and who bears both.
The Anatomy of Neglect
Illegal dumping, property violations, and blight complaints don't spread evenly across Philadelphia. They compound, almost exclusively, in the exact same neighborhoods. A scroll-driven look at how civic failure stacks.
Mapping Philadelphia's illegal-dumping hot spots
In 2024, residents filed thousands of illegal-dumping reports across the city. 19134 alone accounts for nearly a quarter of all reports—and the day-of-week pattern reveals when dumping peaks.
Does calling 311 actually work?
Philadelphia's 311 closure rates vary wildly by category — and response times across the city's zip codes are anything but equal. The data behind the inequity.
You called 311. Then what?
Property and blight complaints land at 311; violation notices come from L&I. Where do those two records line up across the city, and where do they diverge? A zip-by-zip co-occurrence map.
A day in the life of Philadelphia, by 311 call
From the predawn lull to late-night maintenance complaints, every kind of trouble has its hour. The city's 24-hour rhythm in 311 calls — plus the weekly heatmap and how five holidays show up in the data.
The seasonal city
Two categories define Philadelphia's 311 winter — Salting and Shoveling, both literally 100% winter. Almost everything else peaks in summer. The seasonal flip, ranked.
Trash in transit
Two waste-related 311 categories — illegal dumping and missed rubbish/recyclable collection — leave very different fingerprints on the map. A two-layer hex-bin view of where they overlap and where they don't.
The 1 in 10 zip codes
Eight zip codes — out of 48 — drove most of Philly's 2024 illegal-dumping reports. A scroll-driven walk from the citywide map down to one zip's day-of-week fingerprint, contrasted against the median.
Pandemic 311
Six categories of Philly 311 calls, stacked month by month from 2019 through 2024. The shape of the city's complaints didn't return to normal — it just settled at a new normal.
When the city sleeps
Different parts of Philly call about different things at 2 AM. A scroll-driven flyover of four neighborhoods and their 24-hour 311 fingerprints.
Where Philly burns
47% of PFD calls are false alarms. Only 14% are actual fires. And one zip — Kensington — accounts for nearly a fifth of every fire in the city. A scroll through what the Philadelphia Fire Department actually responds to since 2024.
The Narcan Map
Two readings of Philadelphia's overdose crisis: where the deaths landed in 2024, and where the Opioid Response Unit's Narcan kits went. The city's published trend tells you direction; only the raw counts tell you scale.
Stations and zips: who PFD answers to
Sixty-three stations, seven battalions, a million dispatches — and a small handful of zips that swallow most of the call load. A scroll-driven walk through the busiest places and the busiest stations, with the map's data morphing between every beat.
Medic-unit load
PFD's medic units carry roughly four EMS calls for every fire the department answers — and the geography of that load doesn't track the geography of where the medics live. Where raw volume and per-unit workload diverge.
Where shots land
Eight years of shooting victims, plotted block by block, then rolled up by police district. The pre-pandemic baseline, the 2021 peak, the partial recovery — and the three districts that absorb most of every year, regardless of trend.
The non-fire fire calls
Only 14% of PFD dispatches are actual fires. A taxonomy of the other 86% — false alarms, good intent, service calls, hazmat, weather. The operational reality behind the department's name.
EMS vs. fire, by neighborhood
Citywide PFD answers four EMS calls for every fire. Each of Philadelphia's nine broad regions tells its own version of that ratio — Center City leans medical, the river wards carry both.
The day shape of Philly crime
Six categories of PPD incidents, twenty-four hours each. Thefts spike at rush hour; aggravated assaults skew toward bar close; residential burglary tilts to daytime when residents are out. The fingerprint of each crime by hour.
After the parade
The 2024 NYC Pride march concluded on June 30 around 6 PM. In the four hours that followed, hundreds of thousands of attendees dispersed to bars, dinners, after-parties, and homes across the five boroughs. The taxi drop-off pattern shows you exactly where the post-parade economy lives.
Boundaries that don't match
Stand on the corner of any block in New York City, and you are simultaneously inside at least seven different administrative jurisdictions — none of which share boundaries with any of the others. The geographic fragmentation is one of the under-appreciated reasons NYC civic data is so hard to use, and so easy to misuse.
The taxi data found the cellular dead zones
Every yellow cab logs its trip to the TLC's central server in real time. When the cellular signal drops, the meter buffers the trip locally and uploads it later. The TLC published the flag that marks these buffered trips. They probably did not realize they were also publishing a map of NYC's cellular dead spots.
The upzoning paradox
Between 2002 and 2010, New York City upzoned hundreds of blocks — increasing legal density, raising allowed building heights, opening capacity for thousands of new residential units. Eight years later, an academic team rolled the data forward to see what the rents had done. The answer punctured one of the most durable assumptions in U.S. urban policy.
What the congestion toll did to yellow cabs
On January 5, 2025, the Congestion Relief Zone toll went live. Battery Park lost 40% of its yellow cab pickups. World Trade Center dropped 22%. The TLC trip records show which zones the toll hit hardest — and which barely moved.
The tip tells you where you are
Yellow cab tip percentages by pickup zone don't track the income map as neatly as you'd expect. Airport runs, tourist corridors, and short hops have their own tipping logic — all of it baked into every credit card receipt since 2008.
NYC at 3 am
Every yellow cab drop-off between midnight and 5 am in 2023, aggregated by zone. The East Village handles more late-night arrivals than most of the outer boroughs combined. The nocturnal city has a geography — and it's not where you think.
The black car takeover
In 2017 there were more yellow cab trips than Uber and Lyft combined. By 2023 it wasn't close. Seven years of TLC data tells the story of the largest disruption in urban transportation since the car replaced the horse.
The taxi data is coming
1.5 billion rows of NYC taxi trips. The largest mobility dataset any U.S. city publishes — and the first to include the new Manhattan congestion-toll field. Why it doesn't fit our live-Socrata pattern, and what the planned pipeline looks like.
Less than 2 percent
Drug activity, drinking, disorderly youth, graffiti — the categories most invoked when 311 gets framed as a 'social disorder hotline' — together account for under 2% of NYC's 311 calls. Noise alone is roughly 30%. The chaos isn't disorder; the chaos is plumbing.
The unknown pipes
NYC's lead service line inventory looks like a public health story. Scroll through the density maps and it starts to look like a construction program — 231,000 properties across five boroughs, all with a 2037 deadline. The 'Unknown' classification is where the mandate gets complicated.
Mice vs roaches
DOHMH doesn't track pest type as a column on its restaurant inspection data. But it's all there in the violation descriptions, parsed by the inspector. Mice, roaches, flies — the urban biome of NYC's kitchens, mapped per borough.
What the inspectors heard
DOHMH's restaurant inspection data carries a cuisine_description column — one of the few structured cuisine fields on any city portal. Scroll through pizza, Chinese, Latin American, and Japanese density across NYC, and the neighborhoods name themselves.
The algorithmic city
Every year NYC publishes a list of the algorithmic tools its agencies use to make decisions affecting residents' rights and benefits. Local Law 35, the ACS predictive risk-score controversy, the GUARD Act response — and the next horizon of open data.
Twenty-seven months in the Bronx
A 180-unit affordable building was complete in 2022. Eighteen months after the lottery had closed and the waitlist filled, no one had moved in. The lease-up bottleneck that suppresses affordable housing availability for years after construction is physically done.
Who owns this building?
Twelve buildings citywide generated more than 20 Class C — immediately hazardous — housing violations apiece since 2024. The named owner is always an LLC. The beneficial owner is always findable. The corporate-veil-piercing pattern at the heart of NYC tenant advocacy.
The sound of the city
NYC's noise complaints have grown every year since 2010 — population is roughly flat, awareness was already high, but the calls keep coming. Epidemiologists treat the 311 noise feed as a city-scale environmental surveillance layer. The growth is a public-health signal.
The subway tide
Four million weekday riders. The MTA used to know where they boarded but not where they got off — turnstiles only read entries. Then they built an algorithm. The cleanest public view of NYC's transit circulatory system that has ever existed.
NYC's decade of pipe work
231,000 properties. One EPA deadline: 2037. Framing NYC's lead service line replacement program as a construction-industry challenge — which boroughs carry the heaviest load, and what annual pace the city needs to hit.
The maintenance gap
Chicago has subsidized thousands of affordable rental units across its seventy-seven community areas. The streetlights outside them stay dark longer. A first look at whether the city maintains its public right-of-way at the same speed where its housing investments are most concentrated.
When Chicago calls
Chicago picks up the 311 phone at every hour, but the shape of who calls — and what for — changes around the clock. Four service-request categories, four distinct rhythms, one 24-hour dial. Street Light Out peaks at 9 p.m.; Rodent Baiting clusters at 10 a.m.; Aircraft Noise tracks O'Hare's commute lobes.
The swimmer's safety gauge
Chicago Park District buoys publish hourly water temperature, wave height, and turbidity from Lake Michigan. The 24-hour lab E. coli result lags the swimmer's afternoon by a full day. Walking through the last summer of six-sensor coverage — and the slow collapse of the network to one.
Three buckets, one verdict
Chicago classifies every food establishment into one of three risk tiers — High, Medium, Low — that govern how often the city inspects them. Across more than 100,000 inspections since 2020, those three buckets fail at indistinguishable rates. The tier predicts cadence; not outcome. Where the real variation lives: facility type and the trigger that brought the inspector through the door.
Topics
all →Philly 311
Philadelphia's 311 system turns every complaint into a data point. Stories using that database as a lens on city life — service equity, response patterns, and the geography of civic engagement.
Fire & Emergency
Stories drawn from Philadelphia Fire Department dispatch data, EMS call records, the police shooting-victims feed, and public-health emergency records — what the city responds to, and where.
Waste & Illegal Dumping
Eight zip codes drove most of Philly's illegal-dumping reports in 2024. Stories mapping where trash ends up, when it happens, and which neighborhoods bear the burden.
Housing & Blight
The gap between a 311 complaint and an L&I violation notice — mapped zip by zip. Stories on property enforcement, blight, and whether the city's systems talk to each other.
NYC 311
Twenty-four million 311 records since 2010. Noise dominates; the disorder framing doesn't survive the data; the long-arc growth in noise complaints is a public-health surveillance signal.
NYC Housing
The lease-up bottleneck. The corporate-veil offenders. The upzoning paradox. NYC's housing apparatus is data-rich and contradiction-rich; this track maps both.
NYC Environment & Health
The lead pipes the city has lost track of. The pests every restaurant inspector parses out of free-text violation descriptions. The environmental-health surveillance that open data made possible.
NYC Mobility
Four million daily subway riders mapped from one-sided turnstile data. Plus the 1.5-billion-row taxi dataset that's about to need its own pipeline.
NYC Algorithmic Governance
Local Law 35 made NYC the first U.S. city to mandate annual disclosure of every algorithmic tool its agencies use to make decisions affecting residents. The GUARD Act made that disclosure pre-procurement instead of post-facto.
Datasets
Philly 311 service requests
Live snapshot of the City of Philadelphia's 311 requests, queried directly against phl.carto.com via our Cloudflare Worker proxy. Five tabs, real SQL, real maps.
L&I Violations
License & Inspections violation notices issued to Philadelphia properties — the enforcement side of 311. Carto snapshot covering 2007 through March 2020. Join with 311 data to ask: does calling correlate with action?
Philadelphia Fire Department incidents
Every PFD dispatch since 2024-01-01 — false alarms, EMS assists, hazmat, and the ~14% that are actual fires. Quarterly updates from the city's stat360_fire_incidents layer, queried through our ArcGIS proxy.
Vacant Property Indicators
The City's three-layer view of vacancy: ~8.1k vacant buildings, ~25k vacant lots, and ~22.6k census blocks scored by vacancy percentage. The bridge from "someone called about a vacant lot" to "how much of this block is actually empty."
PHS LandCare program
Every parcel the Pennsylvania Horticultural Society LandCare program has stabilized — cleaned, fenced, planted — across Philadelphia. The cleanest public record of where vacancy intervention has actually landed, with year + season + program metadata.
L&I Complaints
Every resident-reported complaint to License & Inspections — unsafe conditions, vacant buildings, illegal use, no-heat, construction without permit. The intake-side companion to L&I Violations; each row is one phone call, not one complaint.
NYC 311 service requests
Live snapshot of New York City's 311 service requests, twenty-four million rows from 2010 to today. Queried via SODA v3 against data.cityofnewyork.us through our Cloudflare worker proxy. Noise dominates; less than 2% is what most people would call 'social disorder.'
NYC TLC taxi trip records
One-and-a-half billion yellow / green / FHV trips since 2009. Stories use build-time DuckDB aggregates. The Playground tab runs DuckDB WASM in the browser — ad-hoc SQL against remote Parquet, no server required.
PLUTO — every NYC tax lot
The Department of City Planning's Primary Land Use Tax Lot Output. ~860K tax lots, ~70 fields each — zoning district, land use, building class, year built, residential units, assessed value. The substrate beneath nearly every quantitative urban-policy paper written about NYC.
NYC Restaurant Inspections
Every sustained violation issued to every food establishment by the Department of Health and Mental Hygiene. One row per violation per inspection. The grade card hung in your favorite spot's window comes from this dataset — and the famous 1900-01-01 placeholder dates.
NYC Lead Service Line Inventory
Per-property classification of which NYC buildings are still served by lead pipes. Published per the EPA's 2024 Lead and Copper Rule Improvements. The headline isn't the lead count — it's the staggering "Unknown" classification, the public-health data void at the heart of the city's 2037 replacement deadline.
HPD Maintenance Code Violations
Every Housing Maintenance Code violation issued by HPD. Joins to PLUTO via BBL. The substrate beneath every "worst landlord" feature, the join key for tenant-advocacy tools that pierce LLC corporate-veil opacity to identify serial offenders.
HPD Affordable Housing Production
Every affordable housing project the city has financed under Housing New York and successor programs. Unit counts segmented by AMI band — what "affordable" actually means depends on which bands you include in the headline.
MTA Subway Origin-Destination
The MTA's algorithmic reconstruction of where 4M daily subway riders actually go. Turnstiles only capture entries; exits are probabilistically inferred from each rider's next entry. The cleanest public view of NYC's transit circulatory system.
NYC LL35 Algorithmic Tools Report
The city's annual algorithmic-tools disclosure required by Local Law 35 of 2021. AI/ML systems used by city agencies that affect rights, liberties, benefits, or safety — including the controversial ACS predictive risk scores that prompted the GUARD Act response. Static editorial; no live adapter.
Chicago 311 service requests
Live snapshot of Chicago's consolidated 311 service requests, ~13.8M rows from 2018 onward. Queried via SODA v3 against data.cityofchicago.org through our Cloudflare worker proxy. Aircraft noise from O'Hare flight paths competes with graffiti, potholes, and rodent baiting for the top-ten slots — a different texture from NYC or Philly.
Chicago Affordable Rental Housing Developments
Every municipally subsidized, deed-restricted rental property the Department of Housing tracks. ~600 rows, joins to 311 and Health Atlas via community area number. Excludes Naturally Occurring Affordable Housing (NOAH) and Housing Choice Voucher placements — what the city directly subsidizes, not the entire affordable stock.
Chicago beach water-quality automated sensors
Hourly Lake Michigan telemetry from Park District buoys at six Chicago beaches: water temperature, wave height, wave period, turbidity, and battery life. Six sensors at the 2014–2015 peak; only Ohio Street Beach is actively reporting in 2026. Companion to the city's 24-hour-lab E. coli advisory.
Chicago food inspections
Every routine canvass, license, and complaint-driven food-establishment inspection by the Chicago Department of Public Health since 2010 — restaurants, daycares, schools, grocers, long-term-care kitchens. ~310K rows. Anonymized at the inspector level: per-sanitarian variance isn't recoverable from the public release. July 2018 schema break.