Briefing for: QN12 Jamaica-St. Albans-Hollis (CD 12 Approximation), Queens. The shape used for QN12 is City Planning's Community District Tabulation Area, an approximation of the official community district. Counts of facilities inside it can differ from counts for the official district boundary.Snapshot 2026-10-05How this briefing was made
Answer
From the sources consulted: New York City's 2017 land cover map (6 inch, from LiDAR and aerial imagery) shows that 67.1% of this area is paved or built over and 32.3% is green (18.9% tree canopy).1
Experimental A satellite land-cover model estimates that 70.7% of this area is paved or built over and 28.4% is green (13.4% tree canopy), on Sentinel-2 scenes from 2026; no change between years is read from it.2 Limits: it estimates the share of each 10 m satellite pixel that is canopy, grass, paving, roof, water or bare ground, learned from the city's 2017 six-inch map, so detail finer than about 30 m is blurred and a tree over a street counts as canopy; against The Nature Conservancy's 2021 six-inch map of the city, on squares it never trained on, it read a typical district's paved share 1.7 points above the map's (at most 7.8 points off in the 46 districts with enough test ground) and its mean error per land-cover group was 4.8 points at best, more than the 3.0 points of the city's 2017 map read as if it were 2021, so the 2017 map is the more accurate source for its year; citywide its maps show 4.2 to 5.0 points less tree canopy than the city's 2017 map in 3 of its 4 yearly maps (2018, 2021, 2026) and 3.2 points more in 1 of its 4 yearly maps (2024), which is the model and its images and not the trees, so its canopy share can be several points off; two images of one summer differ by under 2.0 points in a district's paved share 19 times in 20, but between 2018 and 2024 the shares of 49 of 59 districts differ by more, so its maps of different years are not compared.2 Rely on the city's 2017 land cover map and The Nature Conservancy's 2021 map (both 6 inch) and the city's building footprints for a survey.2
This is an automated hazard-exposure briefing produced by Riprap from live and precomputed data sources. It is informational only and not a substitute for a professional risk assessment. These are public records about a place, not an assessment of any property or of the people who live there. Riprap computes no score or rating, and records can be missing where people report less.
Live here or own property here? FloodHelpNY explains flood zones and insurance for New York City residents.
Figure 1. Plotted: 60 complaints to 311, each placed at its block and not at a house (hollow rings, proxy); 39 public assets from the register. The outline is the Area boundary (NYC DCP 2020 NTAs). FloodNet's sensors are not drawn on this page; they are shown on FloodNet's own dashboard.Map points as a list (99)
Evidence
Source
Finding
Figure
Tier
Data as of
Cite
Behind the answer
NYC Land Cover 2017
NYC Land Cover 2017 Measured, data as of 2017
New York City's 2017 land cover map (6 inch, from LiDAR and aerial imagery) shows that 67.1% of this area is paved or built over and 32.3% is green (18.9% tree canopy).NYC Land Cover 2017 (6 inch), tree canopy and paved shareFigure: 18.9% tree canopy, 67.1% paved or built (2017)
NYC land-cover model (Riprap, experimental) on Copernicus Sentinel-2 Experimental
NYC land-cover model (Riprap, experimental) on Copernicus Sentinel-2 ExperimentalModeled, data as of 2026
Experimental: a satellite land-cover model estimates that 70.7% of this area is paved or built over and 28.4% is green (13.4% tree canopy), on Sentinel-2 scenes from 2026; no change between years is read from it. Limits: it estimates the share of each 10 m satellite pixel that is canopy, grass, paving, roof, water or bare ground, learned from the city's 2017 six-inch map, so detail finer than about 30 m is blurred and a tree over a street counts as canopy; against The Nature Conservancy's 2021 six-inch map of the city, on squares it never trained on, it read a typical district's paved share 1.7 points above the map's (at most 7.8 points off in the 46 districts with enough test ground) and its mean error per land-cover group was 4.8 points at best, more than the 3.0 points of the city's 2017 map read as if it were 2021, so the 2017 map is the more accurate source for its year; citywide its maps show 4.2 to 5.0 points less tree canopy than the city's 2017 map in 3 of its 4 yearly maps (2018, 2021, 2026) and 3.2 points more in 1 of its 4 yearly maps (2024), which is the model and its images and not the trees, so its canopy share can be several points off; two images of one summer differ by under 2.0 points in a district's paved share 19 times in 20, but between 2018 and 2024 the shares of 49 of 59 districts differ by more, so its maps of different years are not compared. Rely on the city's 2017 land cover map and The Nature Conservancy's 2021 map (both 6 inch) and the city's building footprints for a survey. Land cover from satellite, NYC land-cover model (experimental)Figure: 70.7% paved or built, 28.4% green, 13.4% tree canopy (2026)
NYC Department of City Planning Measured, retrieved 2026-07-11
The outline on the map is this area's boundary from the NYC Department of City Planning's 2020 Neighborhood Tabulation Areas; a community district is drawn as the union of its tabulation areas, which approximates the district.Area boundary (2020 Neighborhood Tabulation Areas)
0.8% of this area lies inside the 2012 Hurricane Sandy inundation extent (0.19 km² of the area's 24.7 km²).Share of the neighborhood inside the 2012 Sandy extent
NYC Stormwater Flood Maps (method of the 2021 Stormwater Resiliency Plan; Open Data files of 2024)
NYC Stormwater Flood Maps (method of the 2021 Stormwater Resiliency Plan; Open Data files of 2024) Modeled, data as of 2024-07-03
On the city's stormwater flood map "Limited Flood (1.77 inches/hr) with Current Sea Levels" (the near term), 1.4% of this area is in a rainfall flooding category: 0.9% in "Nuisance Flooding (greater or equal to 4 in. and less than 1 ft.)" and 0.5% in "Deep and Contiguous Flooding (1 ft. and greater)". The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. The city's Stormwater Resiliency Plan (2021) calls its moderate storm "the 10-year storm, with approximately 10 percent chance of occurrence in any given year" and its extreme storm "the 100-year storm, with approximately 1 percent chance of occurrence in any given year".5
On the city's stormwater flood map "Moderate Flood (2.13 inches/hr) with Current Sea Levels" (the near term), 3.1% of this area is in a rainfall flooding category: 1.8% in "Nuisance Flooding (greater or equal to 4 in. and less than 1 ft.)" and 1.3% in "Deep and Contiguous Flooding (1 ft. and greater)". The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. The city's Stormwater Resiliency Plan (2021) calls its moderate storm "the 10-year storm, with approximately 10 percent chance of occurrence in any given year" and its extreme storm "the 100-year storm, with approximately 1 percent chance of occurrence in any given year".6
On the city's stormwater flood map "Moderate Flood (2.13 inches/hr) with 2050 Sea Level Rise", 3.3% of this area is in a rainfall flooding category: 1.9% in "Nuisance Flooding (greater or equal to 4 in. and less than 1 ft.)" and 1.5% in "Deep and Contiguous Flooding (1 ft. and greater)"; 0.0% is in its "Future High Tides 2050" category, which is coastal tidal inundation projected for 2050. The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. The city's Stormwater Resiliency Plan (2021) calls its moderate storm "the 10-year storm, with approximately 10 percent chance of occurrence in any given year" and its extreme storm "the 100-year storm, with approximately 1 percent chance of occurrence in any given year".7
On the city's stormwater flood map "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise", 16.4% of this area is in a rainfall flooding category: 7.5% in "Nuisance Flooding (greater or equal to 4 in. and less than 1 ft.)" and 8.8% in "Deep and Contiguous Flooding (1 ft. and greater)"; 0.0% is in its "Future High Tides 2080" category, which is coastal tidal inundation projected for 2080. The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. The city's Stormwater Resiliency Plan (2021) calls its moderate storm "the 10-year storm, with approximately 10 percent chance of occurrence in any given year" and its extreme storm "the 100-year storm, with approximately 1 percent chance of occurrence in any given year".8
Modeled
Data as of2024-07-03
USGS 3DEP DEM with derived HAND and TWI rasters
USGS 3DEP DEM with derived HAND and TWI rasters Proxy, retrieved 2026-07-11
Median ground elevation 10.55 m NAVD88 (10th percentile 5.43 m).Neighborhood terrain from the USGS 3DEP DEM
NYC Department of City Planning Measured, data as of 2024-02-01
NYC Planning's Community District Profile counts 5 buildings in the 1% annual chance floodplain of this district (the floodplain of FEMA's 2015 preliminary and 2007 maps). The profile prints 0 residential units and 0 residents for this district, a zero that does not fit its own count of 5 buildings, so it is not repeated here as a count. People and buildings in the floodplain (NYC Planning district profile)Figure: Buildings in the floodplain
36 MTA subway entrances in this area (each entrance read at its own point on the maps, with no buffer): 0 inside the 2012 Sandy inundation extent and 17 inside the DEP stormwater map "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise", a modelled scenario (17 in a rainfall flooding category and 0 in its future high tides category, which is coastal tidal inundation projected for 2080 and not rainfall flooding). In a rainfall flooding category of the modelled "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise" map, by station: Jamaica Center-Parsons/Archer (E J Z), Jamaica-179 St (F), Parsons Blvd (F), Sutphin Blvd (F), Sutphin Blvd-Archer Av-JFK Airport (E J Z). The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. MTA subway/rail entrances exposed in the area
1 NYCHA development inside a mapped flood extent in this area (the register lists only developments with 10% or more of their mapped outline inside the 2012 Sandy extent, or their centre point inside one of three modeled DEP stormwater scenarios (Moderate Flood with current and with 2050 sea levels, Extreme Flood with 2080; the Limited Flood map is not tested), not every development): 0 inside the 2012 Sandy inundation extent and 1 inside the DEP stormwater map "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise", a modelled scenario (1 in a rainfall flooding category and 0 in its future high tides category, which is coastal tidal inundation projected for 2080 and not rainfall flooding). Under 10% of the outline inside the 2012 Sandy extent (not counted): FHA REPOSSESSED HOUSES (GROUP X). In a rainfall flooding category of the modelled "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise" map: CONLON LIHFE TOWER. The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. NYCHA developments exposed in the area
NYC Department of Education Measured, data as of 2019-09-04
1 public school inside a mapped flood extent in this area (from the NYC Department of Education's school locations for the 2019 to 2020 school year, charter schools included; the register lists only schools whose location point is inside the 2012 Sandy extent or one of three modeled DEP stormwater scenarios (Moderate Flood with current and with 2050 sea levels, Extreme Flood with 2080; the Limited Flood map is not tested), not every school): 0 inside the 2012 Sandy inundation extent and 1 inside the DEP stormwater map "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise", a modelled scenario (1 in a rainfall flooding category and 0 in its future high tides category, which is coastal tidal inundation projected for 2080 and not rainfall flooding). In a rainfall flooding category of the modelled "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise" map: I.S. 059 Springfield Gardens. The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. Public schools exposed in the area
0 hospitals in this area (each read at the one point the state file gives for it, not across its campus): 0 inside the 2012 Sandy inundation extent and 0 inside the DEP stormwater map "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise", a modelled scenario. The city's stormwater flood maps are modelled scenarios (each a design storm paired with a sea level), not forecasts: their rainfall flooding categories cover public areas and rain only, the city says the map "does not provide the exact depth of flooding at any location", and it is not a flood plain determination. NYS DOH hospitals exposed in the area
FloodNet (New York University and The City University of New York)
FloodNet (New York University and The City University of New York) Measured, fetched 2026-10-05 17:34 UTC
21 FloodNet sensors inside this area have recorded 40 flood events (each a series of depth readings above 10 mm at the sensor, FloodNet's definition) on 8 separate days in the last 3 years (16 of them installed during that period, the latest on 2026-07-09), the most recent starting 2026-08-23 11:15 UTC (every date here is a UTC day). By UTC calendar year: 2 in 2024, 11 in 2025 and 27 in 2026. FloodNet's API lists 14 more events labelled flood here that are still to be verified by a person; Riprap counts verified events only. The highest depth in FloodNet's record for these sensors in that period is 1172 mm (46.1 in) on 2026-05-20, in an event the API marks as verified by a person, at a sensor listed as "noisy" in FloodNet's API when this was read (2026-10-05); that is the sensor's status now, which the API does not give for the day of the event. 6 of the 21 sensors are listed with a status other than "good" in FloodNet's API when this was read ("dead", "driverail_altered", "low_charge", "needs_sensor", "noisy") and recorded 8 of the 40 events. FloodNet ultrasonic depth sensors (NYC)
NYC 311 Service Requests (NYC Open Data) Proxy, data as of 2026-10-05
4499 NYC 311 complaints about flooding and sewer backups filed in Community District QN12 (by the record's community board field) in the last 3 years (since 2023-10-06; eleven descriptors; other sewer complaints, such as odors or missing covers, are not counted): 2731 sewer backup, 1083 catch basin, 532 street flooding, 153 manhole overflow. A count of complaints is a count of reports filed, not of floods: a low count can mean under-reporting and not the absence of flooding, because the propensity to file a 311 request varies with income, language and demographics (studies of other 311 complaint types: Kontokosta, Hong and Korsberg, arXiv:1710.02452; Boxer, Hong, Kontokosta and Neill, Annals of Applied Statistics 19(2), 2025, doi:10.1214/24-AOAS2003). NYC 311 complaints about flooding and sewer backups in the area (3y)
NOAA CO-OPS Measured, fetched 2026-10-05 17:34 UTC
Latest reading at Kings Point, NY, the nearest NOAA tide station in a straight line (13.2 km away, on Long Island Sound): 1.26 ft above MLLW (+0.13 ft vs predicted tide), observed 2026-10-05 17:24 UTC.NOAA tide-gauge water level (nearest station)Figure: Observed water level
National Weather Service (NOAA) Modeled, fetched 2026-10-05 17:34 UTC
No active NWS flood, coastal or tropical storm alerts for this area (read at its centre), checked 2026-10-05 17:34 UTC.NWS active alerts for the area (flood/coastal/tropical storm)
NWS National Water Prediction Service Modeled, fetched 2026-10-05 17:34 UTC
The National Weather Service forecasts a peak water level of 9.1 ft above MLLW at Kings Point, the nearest forecast gauge (13 km away), on 2026-10-08 15:00 UTC (forecast issued 2026-10-05 07:33 UTC), below the gauge's minor flood stage of 10.0 ft.NWS water-level forecast (nearest harbor gauge)Figure: Forecast peak water level
NPCC4 (2024) projects sea-level rise in New York City of 14 to 19 in (0.36 to 0.48 m) by the 2050s and 30 to 50 in (0.76 to 1.27 m) by 2100, relative to 1995-2014, as its middle range (25th to 75th percentile); the 90th percentile is 23 in (0.58 m) by the 2050s and 65 in (1.65 m) by 2100.NPCC4 (2024) sea-level rise projections
1NYC Land Cover 2017, 6 inch (NYC Office of Technology and Innovation; University of Vermont Spatial Analysis Lab)Land Cover Raster Data (2017), 6 inch resolution, NYC Open Data he6d-2qns: eight classes mapped from 2017 LiDAR and aerial imagery. Riprap counts the 6 inch pixels of each class into 30 m cells and reports the shares inside the neighbourhood or district; a tree over a street counts as canopy.Measured, data as of 2017, city_landcover_nta
2NYC land-cover model (Riprap, experimental) on Copernicus Sentinel-2, trained on NYC Land Cover 2017Riprap's NYC land-cover model, trained by scripts/train_cover.py on NYC Land Cover 2017 (6 inch, NYC Open Data) aggregated to 10 m and run by scripts/run_landcover_batch.py on Sentinel-2 L2A scenes; scored against NYC Land Cover 2021 (The Nature Conservancy and UVM) on squares it never trained on. Contains modified Copernicus Sentinel data, via Microsoft Planetary Computer. Experimental: an estimate from 10 m pixels, not a survey.Modeled Experimental, data as of 2026, landcover_nta
4NYC Open Data, Sandy Inundation ZoneNYC Sandy Inundation Zone (NYC Open Data 5xsi-dfpx), share of the neighborhood inside the 2012 extentMeasured, data as of 2015-11-09, sandy_nta
5NYC Stormwater Flood Maps (method of the 2021 Stormwater Resiliency Plan; Open Data files of 2024), Limited Flood (1.77 inches/hr) with Current Sea LevelsNYC Stormwater Flood Maps (NYC Open Data 9i7c-xyvv, Department of Environmental Protection), map "Limited Flood (1.77 inches/hr) with Current Sea Levels", share of the area by the map's flooding categories. Riprap reads this map from the vector tiles of DEP's own map viewer (nyc.gov/stormwater-map, tile service Moderate_5yearMHHW_updateOB_VTile1_61424), because the NYC Open Data file for it is a compressed geodatabase that open tools cannot read; the other three maps are read from the NYC Open Data files. The viewer's tiles and the Open Data files are not identical where both can be read (for the Moderate map with current sea levels the deep and contiguous category matches and the nuisance category differs by about a tenth of its area), so this reading may differ from the Open Data file for the Limited map. Map disclaimer, from DEP's own map items (arcgis.com/home/item.html?id=5b82c08be55d4f30bf28d265ab8e4a49): the map "is intended to be an informational tool and does not provide the exact depth of flooding at any location", shows "the relative risk of flooding in public areas from stormwater runoff due to rain only", and "shall not be used for the design, modification, or construction of improvements to real property or for flood plain determination". The caveat on an outside reading quotes NYC Emergency Management, Hazard Mitigation Plan, flooding profile (https://nychazardmitigation.com/documentation/hazard-profiles/flooding/).Modeled, data as of 2024-07-03, dep_limited_current_nta
6NYC Stormwater Flood Maps (method of the 2021 Stormwater Resiliency Plan; Open Data files of 2024), Moderate Flood (2.13 inches/hr) with Current Sea LevelsNYC Stormwater Flood Maps (NYC Open Data 9i7c-xyvv, Department of Environmental Protection), map "Moderate Flood (2.13 inches/hr) with Current Sea Levels", share of the area by the map's flooding categories. Map disclaimer, from DEP's own map items (arcgis.com/home/item.html?id=5b82c08be55d4f30bf28d265ab8e4a49): the map "is intended to be an informational tool and does not provide the exact depth of flooding at any location", shows "the relative risk of flooding in public areas from stormwater runoff due to rain only", and "shall not be used for the design, modification, or construction of improvements to real property or for flood plain determination". The caveat on an outside reading quotes NYC Emergency Management, Hazard Mitigation Plan, flooding profile (https://nychazardmitigation.com/documentation/hazard-profiles/flooding/).Modeled, data as of 2024-07-03, dep_moderate_current_nta
7NYC Stormwater Flood Maps (method of the 2021 Stormwater Resiliency Plan; Open Data files of 2024), Moderate Flood (2.13 inches/hr) with 2050 Sea Level RiseNYC Stormwater Flood Maps (NYC Open Data 9i7c-xyvv, Department of Environmental Protection), map "Moderate Flood (2.13 inches/hr) with 2050 Sea Level Rise", share of the area by the map's flooding categories. The Stormwater Resiliency Plan (2021) describes its moderate scenario as "approximately two inches of rain falling in one hour (also referred to as the 10-year storm, with approximately 10 percent chance of occurrence in any given year) combined with 2.5 feet of SLR". Map disclaimer, from DEP's own map items (arcgis.com/home/item.html?id=5b82c08be55d4f30bf28d265ab8e4a49): the map "is intended to be an informational tool and does not provide the exact depth of flooding at any location", shows "the relative risk of flooding in public areas from stormwater runoff due to rain only", and "shall not be used for the design, modification, or construction of improvements to real property or for flood plain determination". The caveat on an outside reading quotes NYC Emergency Management, Hazard Mitigation Plan, flooding profile (https://nychazardmitigation.com/documentation/hazard-profiles/flooding/).Modeled, data as of 2024-07-03, dep_moderate_2050_nta
8NYC Stormwater Flood Maps (method of the 2021 Stormwater Resiliency Plan; Open Data files of 2024), Extreme Flood (3.66 inches/hr) with 2080 Sea Level RiseNYC Stormwater Flood Maps (NYC Open Data 9i7c-xyvv, Department of Environmental Protection), map "Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise", share of the area by the map's flooding categories. The Stormwater Resiliency Plan (2021) describes its extreme scenario as "approximately 3.5 inches of rain falling in one hour (also referred to as the 100-year storm, with approximately 1 percent chance of occurrence in any given year) combined with 4.8 feet of SLR". Map disclaimer, from DEP's own map items (arcgis.com/home/item.html?id=5b82c08be55d4f30bf28d265ab8e4a49): the map "is intended to be an informational tool and does not provide the exact depth of flooding at any location", shows "the relative risk of flooding in public areas from stormwater runoff due to rain only", and "shall not be used for the design, modification, or construction of improvements to real property or for flood plain determination". The caveat on an outside reading quotes NYC Emergency Management, Hazard Mitigation Plan, flooding profile (https://nychazardmitigation.com/documentation/hazard-profiles/flooding/).Modeled, data as of 2024-07-03, dep_extreme_2080_nta
10NYC Department of City Planning, Community District Profiles (floodplain indicators)NYC Department of City Planning, Community District Profiles, floodplain indicators (data version 2024-02). The 1% annual chance floodplain is from FEMA's 2015 preliminary and 2007 flood insurance rate maps; population is the 2010 census by census block.Measured, data as of 2024-02-01, dcp_floodplain_nta
11MTA, subway/rail entrances registerMTA subway/rail entrances, cross-referenced with Sandy 2012 + DEP extreme 2080.Measured, data as of 2025-12-05, mta_entrance_exposure
12NYCHA developments registerNYCHA public housing developments, cross-referenced with Sandy 2012 + DEP extreme 2080.Measured, retrieved 2026-05-01, nycha_development_exposure
14NYS DOH hospitals registerNYS DOH Health Facility General Information (vn5v-hh5r) hospitals in NYC, cross-referenced with Sandy 2012 + DEP extreme 2080.Measured, retrieved 2026-07-11, doh_hospital_exposure
15FloodNet (New York University and The City University of New York)FloodNet street flood sensors. Flood events and sensor status read from the FloodNet Data API (api.floodnet.nyc, an early-access beta) at the retrieval time shown. A flood event is a series of depth measurements greater than 10 mm at the sensor (FloodNet's definition); a depth is measured at one point and does not show the depth on every part of the street. Riprap counts the events the API marks as verified by a person. FloodNet's published cautions about a depth: "most FloodNet sensors are mounted over sidewalks and are thus unable to measure floods in the roadbed until the water rises above the height of the curb"; the depth at the street's lowest point differs from the reading by the sensor's height above that point; "a single anomalous data point, measured during a flood event" may exaggerate a maximum depth; and a sensor may miss a flood "if it was offline and awaiting repair or had not been deployed yet or retired" (FloodNet's NYC Open Data description, dataset aq7i-eu5q). Ten rows of FloodNet's deployments table are NOAA and USGS tide gauges (deploy_type "tidal"); Riprap does not count them as FloodNet sensors. Riprap names no sensor, because FloodNet's licence forbids reposting its records: each verified event can be found by its date and depth in FloodNet's own table on NYC Open Data, "FloodNet: Street Flooding Events Measured by FloodNet Sensors" (https://data.cityofnewyork.us/d/aq7i-eu5q), and on its dashboard (https://dataviz.floodnet.nyc). Cite: Mydlarz et al. (2024), Water Resources Research 60, e2023WR036806, https://doi.org/10.1029/2023WR036806; Silverman et al. (2022), Water Research, 118648, https://doi.org/10.1016/j.watres.2022.118648. Licence: FloodNet data and content derived from it are CC BY-NC-SA 4.0 (https://creativecommons.org/licenses/by-nc-sa/4.0/), not Riprap's Apache-2.0. Riprap is independent of FloodNet and not endorsed by it.Measured, fetched 2026-10-05 17:34 UTC, floodnet
16NYC 311 Service Requests (NYC Open Data)NYC 311 Service Requests from 2020 to Present (NYC Open Data dataset erm2-nwe9), complaints about flooding and sewer backups in the area (the sentence states how the area was counted, and the window). A neighbourhood is counted from the rows in its bounding box that fall inside its outline; a community district by the record's community_board field. Counted: requests of complaint type "Sewer" or "Sewer Maintenance" whose descriptor is one of eleven flood and sewer descriptors (street flooding, sewer backup, catch basin, highway flooding, manhole overflow and rain garden flooding, under their coded and plain names; the list is in app/context/nyc311.py), created on or after the start date the sentence gives (midnight UTC, 365 days for each year of the window). A request filed under both descriptor names at the same place within ten minutes is counted once. This citation's query_url is the Socrata query for the counted rows, with no house number or coordinate selected. Complaints are shown at the block, never the house number.Proxy, data as of 2026-10-05, nyc311_nta, the query for these rows
19NWS National Water Prediction Service, gauge forecastNational Weather Service, National Water Prediction Service, official water-level forecast and flood stages for the nearest harbor gauge.Modeled, fetched 2026-10-05 17:34 UTC, nws_water_forecast
20NPCC4, New York City Panel on Climate Change (2024)Braneon, C. et al. (2024). NPCC4: New York City climate risk information 2022, observations and projections. Annals of the New York Academy of Sciences, Vol. 1539 (doi:10.1111/nyas.15116), Table 1: projections for sea level rise in New York City, relative to 1995-2014.Modeled, data as of 2024, npcc4_slr
What was checked
Sources consulted (20)
Area boundary (2020 Neighborhood Tabulation Areas)
Share of the neighborhood inside the 2012 Sandy extent
NYC Stormwater Flood Maps, Extreme Flood (3.66 inches/hr) with 2080 Sea Level Rise, share of the area
NYC Stormwater Flood Maps, Moderate Flood (2.13 inches/hr) with 2050 Sea Level Rise, share of the area
NYC Stormwater Flood Maps, Moderate Flood (2.13 inches/hr) with Current Sea Levels, share of the area
NYC Stormwater Flood Maps, Limited Flood (1.77 inches/hr) with Current Sea Levels, share of the area
Neighborhood terrain from the USGS 3DEP DEM
NYC Land Cover 2017 (6 inch), tree canopy and paved share
Land cover from satellite, NYC land-cover model (experimental)
FloodNet ultrasonic depth sensors (NYC)
NYC 311 complaints about flooding and sewer backups in the area (3y)
NOAA tide-gauge water level (nearest station)
People and buildings in the floodplain (NYC Planning district profile)
MTA subway/rail entrances exposed in the area
NYCHA developments exposed in the area
Public schools exposed in the area
NYS DOH hospitals exposed in the area
NWS active alerts for the area (flood/coastal/tropical storm)
NWS water-level forecast (nearest harbor gauge)
NPCC4 (2024) sea-level rise projections
Not checked for this question (1)
Construction jobs in the older DOB permit file inside the neighborhood
Out of scope
This briefing is not a flood zone determination, an engineering assessment or advice. Where a probe was offline at run time, the relevant section omits that signal.
How this briefing was made
Checks run: citations and numbers on every claim; lead rules on the answer, which is the cited text word for word.
Answered by rules over the question's words; no language model was used.
Precomputed snapshot, generated 2026-10-05 17:34 UTC from Riprap commit b0398f64. Live readings (tides, alerts, sensors) are as of that time.
5 Stones, 22 registered source functions: 22 ran.
Models in this briefing
NYC land-cover model (experimental), weights not published.
An earlier batch run; its saved output is read; not run for this briefing.