{"id":"wildfire-near-water","slug":"wildfire-near-water","name":"Wildfire Near Water Dataset","description":"Annual burned area within fifty kilometres of each United States river gauge, borehole, monitoring station and reservoir site Hydrionis reports, from 1984 to 2019. Derived from federal wildland fire perimeters: 1,881 measurement points had at least one mapped fire in range, and the largest single point-year is the Yellowstone fires of 1988 at the Yellowstone River outlet.","methodology":"Fire perimeters are fetched from the Interagency Fire Perimeter History service with their centroids, and the mapped area of every perimeter whose centroid falls within fifty kilometres of a Hydrionis measurement point is summed by year. Method burned-area-within-radius 1.0.0, stored with basis derived. Areas are converted from the acres the publisher states to hectares. Years are filled with zeros across the whole span, because a year in which nothing burned in range is a real result of the calculation and a reader most wants continuity in the quiet years either side of a fire.","domains":["ecosystem"],"metricIds":["burned-area-within-50km"],"subjectScope":"United States river gauges, boreholes, monitoring stations and reservoir sites with a mapped fire within 50 km","cadence":"irregular","version":"1.0.0","released":"2026-08-27","changelog":[{"version":"1.0.0","date":"2026-08-27","summary":"First release.","additions":["Burned area within 50 km of 1,881 United States measurement points, 1984–2019."],"methodVersion":"burned-area-within-radius 1.0.0"}],"limitations":["A radius is not a catchment. A fire fifty kilometres away may be in another basin entirely, and one just outside the circle may sit directly upstream — the circle knows nothing about which way water flows.","The perimeter centroid stands in for the whole fire, so a long fire straddling the boundary is counted wholly in or wholly out.","Points within fifty kilometres of one another share fires. Their values are not independent and must never be summed.","Coverage ends in 2019 because the source layer does. Perimeters from 2020 are published separately and are not held, so this dataset must not be read as showing wildfire declining after 2019.","A zero means no mapped perimeter fell within the radius. It does not mean nothing burned: small fires and unmapped fires are absent from the source.","Nothing here measures water. Burned area near a gauge is not evidence of turbidity, sediment or nutrient change at it."],"context":{"hydrionisClass":"water-driver","whyHeld":"Fire changes what a catchment does with rain. A burned hillside sheds water faster and carries ash, sediment and nutrients with it, and the consequence for a water supply usually arrives with the first heavy storm after the fire rather than with the fire itself. This records how much burned near places Hydrionis measures water. It records nothing about whether the water changed, and is not a measurement of any river, reservoir or aquifer.","waterRelevance":["Post-fire erosion, turbidity and sediment load","Nutrient and ash flushes into drinking-water catchments","Changed runoff response of a burned catchment to rainfall","Reservoir sedimentation after fire in the contributing area"],"suitableUses":["Showing that a large fire occurred near a gauge in a given year, with the distance stated","Selecting gauges that had substantial burned area nearby, as candidates for closer study","Placing a water-quality record in the context of a known fire year"],"unsuitableUses":["Concluding that water quality changed because a fire burned nearby — that requires the water record itself, and severity, slope, soil and subsequent rainfall besides","Treating the radius as a catchment, or the sum as the area of catchment burned","Summing across nearby points, which double-counts the same fires","Any statement about wildfire trends after 2019"],"joinDimensions":[{"kind":"measured-proximity","on":"Great-circle distance from a fire perimeter centroid to a Hydrionis measurement point, within 50 km","limitation":"Proximity is not catchment membership and carries no direction. A fire within the radius may drain away from the point entirely, and one outside it may drain directly to it."}],"relationshipConfidence":"proximate","eligibility":{"api":true,"download":true,"overlay":true,"publicPage":false}},"observationCount":48816,"seriesCount":1356,"subjectCount":1356,"from":1984,"to":2019,"sourceIds":["nifc-fire-perimeter-history"],"units":["ha"],"redistributable":true,"commerciallyReusable":true,"citation":"Hydrionis (2026), Wildfire Near Water Dataset, version 1.0.0. Retrieved from https://hydrionis.com/data/datasets/wildfire-near-water/","downloads":[{"file":"/downloads/observations-ecosystem-nifc-fire-perimeter-history.csv","format":"CSV","label":"ecosystem observations from NIFC (73,359 rows)"}],"apiPath":"/api/v1/datasets/wildfire-near-water.json","lastFetched":"2026-08-27","fields":[{"id":"burned-area-within-50km","name":"Burned area within 50 km","definition":"Total mapped wildfire area in a year whose perimeter centroid lies within fifty kilometres of this measurement point.","unit":"ha","nativeGeography":["river-gauge","monitoring-station","borehole","reservoir-site"],"comparabilityNotes":"A radius is not a catchment: a fire fifty kilometres away may be in another basin, and one just outside the circle may sit directly upstream. Points within fifty kilometres of each other share fires, so their values are not independent and must not be summed. A zero means no mapped perimeter fell in the radius, not that nothing burned."}]}