Where this answer comes from.
Each of these has its own page naming the office that publishes it, how often it updates, and what it cannot answer. Rebuilt from the ParcelOps source directory on September 9, 2026.
USACE National Inventory of Dams
Which listed dams sit near a site, the hazard class the regulator assigned each one, and its condition and inspection record.
FEMA Flood Zones
Flood hazard maps from FEMA, for an early check on a US property.
USGS Water Observations
USGS streamflow, stage, site, daily-value, water-quality, and groundwater observations.
Where this stops.
The part a search result will not tell you, and the part worth reading before this answer goes into a decision.
- Upstream and downstream cannot be told apart here. A dam across a ridge and a dam on the same creek return the same way, and only terrain and the stream name separate them.
- A blank condition assessment means unassessed or unreported. It does not mean fine, and a blank emergency action plan flag means unknown rather than no.
- This is not a flood determination. Most dam failure inundation areas are not mapped as special flood hazard areas, so the two answers are not substitutes in either direction.
- State regulated and federally regulated dams are inspected under different programs on different cycles, and the inventory reports whichever regulator supplied the record.
What people ask next.
A high hazard dam is half a mile away. Should I be worried?
Not from that fact alone. High hazard is a statement about consequences downstream if it failed, and plenty of high hazard dams are in good condition and inspected on schedule. The signals that mean something are a poor or unsatisfactory condition rating, a long gap since the last assessment, and terrain that puts the property in a plausible flow path. The first two come back with the result. The third does not.
Where do I get the actual inundation map?
From the dam owner or the state dam safety program. Breach inundation studies exist for most high hazard dams, they are not part of the national inventory, and several states restrict how they are shared. The inventory record gives you the owner, the regulator, and the identifier to ask with, which is usually the slow part.
Questions people ask alongside this one.
What census tract is this address in?
Federal program designations are published by census tract, not by address. How to resolve an address to its state, county, tract, and block codes, and why the vintage matters.
Is this property in a flood zone?
A flood zone answer is a letter read off a specific FEMA map panel with an effective date. What each zone means, and why outside a zone is not the same as safe.
Are there wetlands on this property?
The national wetlands inventory is a map layer compiled from imagery, not a jurisdictional determination. What the classification codes mean and where the layer stops.
Is this property in a wildfire risk area?
There is no national wildfire zone the way there is a flood zone. What the modeled risk metrics at a point actually describe, and what decides one house.
Have earthquakes been recorded near this site?
The published earthquake catalog around a coordinate, with magnitude, depth, and date. Why a quiet catalog is a statement about the instrument record, not about hazard.
What disasters have been declared in this county?
Federal disaster declarations are made at county level. The declaration history, the flood insurance claim pattern, and what a declaration does and does not say about one address.
The lanes this question belongs to.
A lane page lists every source that kind of work reads, not only the ones behind this question, and states where the whole lane stops.
Run it on a property you already know.
The free plan includes 50 tool calls for the life of the account. They never expire and never refill, and there is no credit card. Ask this question about an address whose answer you can check.