FloodNet New York City · the measured record Live page retired

This page no
longer reads
the sensors

It used to ask every FloodNet gauge in New York City whether there was water on its corner, once a minute. It has been retired on purpose.

Why

This page was built on FloodNet's real-time endpoint. In July 2026 the project confirmed that endpoint is deprecated and does not carry their full quality-control filtering. Their clean, human-labelled record is published on NYC Open Data, and that labelling is what accounts for its roughly two-week lag.

Asked about a set of implausible readings, FloodNet confirmed the real-time API is not subject to their full filtering stages, that it will not be available much longer, and that no public real-time replacement is planned. The project steps back in March 2027, when the Department of Environmental Protection takes over operations. Their recommendation was to rely on the NYC Open Data record instead.

In the unvetted feed, across the 30 days to 28 July 2026, 33 of 399 reporting gauges returned a maximum of two feet or more and 17 returned three feet or more, topping out at 70.5 inches. FloodNet's vetted record contains 2,604 events since 2021, of which 25 in total ever exceeded two feet. One gauge reported 70.5 inches exactly once in a month and has a half-inch published history. Another held 38 inches for ten hours on a day with no rain anywhere in the city.

Filters can catch most of that, and this page's did. But filtering unvetted data is inference from the shape of a trace rather than measurement, and a page that leads with a number in inches should be built on numbers someone has verified. So the work has moved to the record that is already checked, instead of publishing readings with a caveat attached to every one.

Where the work went

The historical map is the durable half of this project. It runs entirely on FloodNet's published event data from NYC Open Data, which is the same source their own quality pipeline produces, and it covers every flood the network has recorded since November 2020.

Go to the measured record

What was lost, and what was kept

  • Gone: live depths, the live map, the right-now count, and the 7-day and 30-day live windows.
  • Kept: every historical comparison, which never depended on the live feed.
  • Kept in version control: the full live page, including the fault tests written to screen the unvetted feed. Those found three distinct instrument failure modes and are documented in the repository history.

FloodNet is a research collaboration of CUNY, NYU and New York City agencies. This is an independent civic-data project, not affiliated with FloodNet or the City of New York, and nothing here should be read as criticism of a network that publishes its data openly and answered a stranger's questions candidly. Their own dashboard is at dataviz.floodnet.nyc.