San Francisco Is Quietly Replacing Thousands of Duplicate Property Images — Here's How It Stacks Up Against Amsterdam and Seoul

San Francisco's Planning Department confirmed this spring that it had identified more than 14,000 duplicate or outdated images embedded across its publicly accessible property parcel database — a figure that has quietly grown since the city digitized its assessor records in a phased rollout beginning in 2019. The duplicates range from mislabeled street-view captures of Tenderloin SROs to redundant aerial shots of Mission District mixed-use parcels filed during permit reviews. The department has been working through a backlog using a combination of in-house staff and a contract with a local geospatial firm to flag and replace the images.

The issue matters now because San Francisco, like a handful of comparable global cities, is mid-sprint on a housing production emergency that depends on fast, accurate parcel data. Bad imagery slows environmental review, confuses contractors pulling permits at the Department of Building Inspection on Duboce Avenue, and creates friction for community groups trying to assess development proposals through the city's online planning portal. With Mayor Daniel Lurie pressing city hall to streamline permitting after years of procedural gridlock under prior administrations, even an arcane database problem carries real cost.

The city's Office of Digital Services, headquartered at City Hall on Dr. Carlton B. Goodlett Place, has been coordinating with the Planning Department since January 2026 to pilot an automated deduplication protocol. The program uses perceptual hashing — a technique that generates a fingerprint for each image and flags near-identical matches — to pre-screen submissions before they enter the live database. The SF Heritage Foundation, which tracks changes to historic structures across the city, has separately raised concerns that the cleanup process has in some cases removed the only surviving photographic record of pre-renovation building facades, particularly in the Haight-Ashbury and Western Addition neighborhoods.

How Other Cities Are Handling the Same Problem

Amsterdam's city government began a comparable deduplication effort for its Basisregistratie Adressen en Gebouwen — the national addresses and buildings registry — in 2022. By early 2025, municipal officials there reported clearing roughly 28,000 duplicate records from a database covering the entire Netherlands, according to published documentation from the Dutch Kadaster land registry authority. Seoul took a different approach: the Seoul Metropolitan Government embedded image validation directly into its Smart City Data Hub platform, requiring third-party uploader certification before any property image is accepted, a standard the city introduced in 2023.

San Francisco's manual-plus-automation hybrid sits somewhere between those two models. Unlike Amsterdam, which centralized the cleanup at the national registry level with dedicated federal funding, San Francisco is managing the problem department by department, with no single city-wide mandate or dedicated budget line publicly announced for fiscal year 2026-27. Unlike Seoul's prevention-first approach, the city is still largely doing remediation — fixing errors after they have already entered the system. San Francisco's population density in affected neighborhoods, particularly SoMa and the Tenderloin, means the error rate per square mile is among the highest of any comparable American city managing an active permitting surge.

What Comes Next for Property Records in the City

The Planning Department's internal target, according to materials presented at a March 2026 commission hearing, is to clear the identified duplicate backlog by the fourth quarter of 2026. Whether that timeline holds depends in part on staffing. The department has posted two GIS analyst positions, with salaries listed between $98,000 and $119,000 annually, that remain unfilled as of this month.

For residents and small developers navigating the system in the meantime, the practical advice from planning staff has been to file original, high-resolution photographs directly with permit applications rather than reusing images pulled from third-party real estate platforms like Zillow or Redfin — a practice that has been a primary source of the duplicate problem. The Department of Building Inspection's public counter on Duboce Avenue can flag specific parcel image conflicts before a permit application advances, saving weeks of back-and-forth. The city's long-term goal is a unified property image repository that validates submissions at intake — closer to the Seoul model — but no contract for that system has been publicly awarded.