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nid.sec.usace.army.mil/

USACE National Inventory of Dams

Freeauth: noneProvider terms#transport-shipping#geospatial#risk#infrastructure#historical-data✓ verified Nov 1, 2026

USACE National Inventory of Dams

The U.S. Army Corps of Engineers publishes National Inventory of Dams records through a public REST API and nationwide CSV and GeoPackage downloads. Records include dam identifiers, owners, coordinates, purpose, dimensions, storage, completion year, inspection date, hazard classification, condition and regulatory fields; no key is required for public data.

Coverage

The nationwide CSV fetched on 2026-11-01 contained 92,692 dams across 52 state or territory values and stated that the data were last updated on 2026-10-30. The inventory covers qualifying dams in the United States and its territories; the provider does not state a fixed refresh interval.

Verdict

A national infrastructure signal for water-storage, flood-control, hydropower and navigation assets near transport corridors and operating regions. Location, purpose, capacity, hazard and inspection fields can add exposure context, but the site states that it is informational and not real-time. Hazard potential describes consequences rather than failure likelihood, and inspection, condition or ownership fields can be missing or old because source agencies maintain the underlying records. Preserve the file's update date and do not treat the inventory as an emergency-warning service.

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Use in your agent

Load the nationwide USACE dam CSV into Parquet. Checked against the provider's documentation on Nov 1, 2026.

Raw skill file (/skills/usace-national-inventory-of-dams.md)Also in our MCP server: call get_ingestion_skill with {"slug": "usace-national-inventory-of-dams"}.

Access

  • No account or key. The national CSV and GeoPackage endpoints are public downloads.
  • The CSV has a one-line update-date preamble before the column header.

Request

bash
curl -O 'https://nid.sec.usace.army.mil/api/nation/csv'

Format

CSV with a metadata preamble followed by dam rows covering identifiers, owners, location, dimensions, storage, purpose, inspection, hazard, condition and regulatory fields.

Load into pandas and Parquet

Needs Python 3 with requests, pandas and pyarrow.

python
"""USACE nationwide National Inventory of Dams CSV -> pandas -> Parquet."""
import io
import requests
import pandas as pd

URL = "https://nid.sec.usace.army.mil/api/nation/csv"
r = requests.get(URL, timeout=120)
r.raise_for_status()
text = r.content.decode("utf-8-sig")
updated = text.splitlines()[0].split(",", 1)[1]
df = pd.read_csv(io.StringIO(text), skiprows=1, low_memory=False)
df.to_parquet("national_inventory_of_dams.parquet", index=False)
print(len(df), "dams", "data last updated", updated,
      "states/territories", df["State"].nunique())

Run by us on 2026-11-01 (python 3.13.5 | pandas 3.1.0 | pyarrow 26.0.0 | requests 2.34.2). Result: 92692 dams data last updated 2026-10-30 states/territories 52

Limits

  • Rate limit: Not stated.
  • The checked national CSV was about 69 MB.
  • The provider does not state a fixed update schedule.

Quirks

  • Skip the first CSV line and retain its date as file-level provenance.
  • Hazard Potential Classification describes downstream consequences if a failure occurs; it is not a probability of failure.
  • Dates and condition fields can be blank or old, and the source agency is identified per record.
  • The inventory is not real-time and must not be used as an emergency-warning feed.

Terms and attribution

  • USACE makes the public API and nationwide downloads available without a key.
  • The API documentation says NID services are available for integration into applications.
  • The NID site states that it is informational and not real-time; no separate open-data licence was stated.

Sources

Information and education only. Not financial, investment, legal or tax advice. Listings can be inaccurate, incomplete or out of date and are provided "as is". Free tiers, limits and licenses belong to each provider and can change, so check the provider's own terms before you rely on them. Terms & Disclaimer

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