National Inventory of Dams with Hazard Potential Classifications

The National Inventory of Dams (NID) contains all known dams in the United States and its territories that meet the federal definition. It includes over 70 data fields per dam, covering location, size, purpose, type, last inspection, and regulatory facts. The dataset is maintained by the U.S. Army Corps of Engineers in cooperation with state and federal agencies.

Use Cases

• Map dam locations and analyze spatial distribution of high hazard potential dams using location and hazard classification fields.
• Assess infrastructure risk by correlating dam type and last inspection date with hazard potential classifications.
• Analyze dam purposes (e.g., irrigation, flood control) across different size and storage capacity categories.
• Model reservoir storage capacity and dam height relationships for dams meeting specific federal size thresholds.

Strengths

• Contains over 70 data fields for each dam, providing detailed attributes.
• Nationally comprehensive, covering all known dams in the U.S. and its territories meeting federal criteria.
• Includes specific hazard potential classifications (high, significant, low) based on downstream impact criteria.
• Maintained by authoritative sources like the U.S. Army Corps of Engineers and state agencies.

Limitations

• Exact row count and update frequency are not specified in the provided input.
• Data completeness relies on periodic updates from multiple state and federal agencies, which may introduce lags.
• The definition for inclusion (e.g., specific height and storage thresholds for low hazard dams) may exclude smaller structures.

Provenance

Source

U.S. Army Corps of Engineers National Inventory of Dams (NID), in cooperation with the Association of State Dam Safety Officials and federal/state agencies.

Collection Method

Compiled and maintained as a national registry from submissions by state, territorial, and federal agencies.

Freshness

Data was last updated on 2026-02-03, but a specific update schedule is not stated.

Geography

United States and its territories.