Data sources

Every hazard and terrain value on Outpost comes from a government source. This page lists each dataset, the agency that publishes it, and how Outpost uses it.

Screening only — not a legal or official determination. Verify with the issuing agency.

How current the data is

Outpost’s data is as of October 23, 2026 and is refreshed monthly. Most layers come from a dated snapshot of each agency’s data. Four scorecard checks ask the agency’s own service at the moment you check a point: USDA Forest Service Wildfire Hazard Potential (on federal land), California Geological Survey landslide susceptibility, U.S. Fish & Wildlife Service wetlands, and USGS elevation and slope.

Boundaries are simplified for the web and can lag official updates. Agencies publish these data as-is, without warranty. USFWS notes its critical habitat files are not the legal source for boundaries (the Federal Register rule is), and DTSC says EnviroStor is for information only.

Wildfire

• Fire Hazard Severity Zones in State Responsibility Areas (2024 map)CAL FIRE, Office of the State Fire MarshalMap layer and scorecardFire hazard zones guide
• Fire Hazard Severity Zones in Local Responsibility Areas (2025 recommended maps)CAL FIRE, Office of the State Fire MarshalMap layer and scorecardFire hazard zones guide
• State Responsibility Area boundariesCAL FIREScorecard: whether a point is in a state, local or federal fire protection areaFire hazard zones guide
• Fire perimeters (FRAP), recent yearsCAL FIRE Fire and Resource Assessment ProgramMap layer and scorecardFire hazard zones guide
• Wildfire Hazard PotentialUSDA Forest ServiceMap layer (federal land) and live scorecard checkFire hazard zones guide

Flood

• National Flood Hazard Layer (NFHL)FEMAMap layer and scorecardFlood zones guide

Geology

• Alquist-Priolo Earthquake Fault ZonesCalifornia Geological SurveyMap layer and scorecardEarthquake zones guide
• Alquist-Priolo fault tracesCalifornia Geological SurveyScorecard: fault namesEarthquake zones guide
• Seismic Hazard Zones: liquefactionCalifornia Geological SurveyMap layer and scorecardEarthquake zones guide
• Map Sheet 58: deep-seated landslide susceptibilityCalifornia Geological SurveyMap layer and live scorecard checkLandslides guide

Terrain

• 3D Elevation Program (3DEP)U.S. Geological SurveyLive scorecard check: elevation, slope and the terrain profileLandslides guide

Water and habitat

• National Wetlands Inventory (NWI)U.S. Fish & Wildlife ServiceMap layer and live scorecard check (Outpost’s copy of the map if the live service is slow)Wetlands and habitat guide
• Final critical habitat (Endangered Species Act)U.S. Fish & Wildlife Service (ECOS)Map layer and scorecardWetlands and habitat guide
• SGMA 2019 groundwater basin prioritizationCalifornia Department of Water ResourcesMap layer and scorecardGroundwater basins guide
• Critically overdrafted basinsCalifornia Department of Water ResourcesMap layer and scorecardGroundwater basins guide

Contamination

• Superfund National Priorities List (NPL) sitesU.S. EPAMap layer and scorecard (sites within 500 ft)Contaminated sites guide
• EnviroStor cleanup and investigation sitesCalifornia Department of Toxic Substances ControlMap layer and scorecard (sites within 500 ft)Contaminated sites guide
• Leaking underground storage tank (LUST) cleanup sitesCalifornia State Water Resources Control BoardMap layer and scorecard (sites within 500 ft)Contaminated sites guide

Jurisdiction

• Coastal Zone boundaryCalifornia Coastal CommissionMap layer and scorecard

Base map and search

• California state boundaryU.S. Census BureauKeeps searches and map clicks inside California
• Satellite imagery, streets, 3D view and address search© Mapbox © OpenStreetMap © MaxarBase map and address search (not hazard data)

The California Coastal Zone

Outpost shows the California Coastal Commission’s digital Coastal Zone boundary, and the scorecard says whether a point is inside it.

• By law the Coastal Zone generally extends 1,000 yards inland from the mean high tide line. In significant estuary, habitat and recreation areas it reaches farther, up to the first major ridgeline or five miles, whichever is less, and in developed urban areas it is generally narrower.
• Development in the Coastal Zone generally needs a Coastal Development Permit, from the Commission or from a city or county with a certified Local Coastal Program.
• The Commission notes that its digital boundary isn’t the official version adopted in 1977 and may not remove the need for a formal boundary determination.

Official source: California Coastal Commission: Coastal Zone boundary.

Approximate site locations

Some EnviroStor, leaking tank and Superfund records give only an approximate location. Outpost leaves the ones it can identify out of the 500-foot checks; see the contaminated sites guide for how they are shown.