---
pretty_name: "Dam safety hazard classification, inspection frequency, and owner obligations by US state"
license: other
license_name: source-terms-cited
license_link: https://referencesource.org/state-dam-safety-classification/
language:
- en
tags:
- reference-data
- provenance
- referencesource-org
configs:
- config_name: default
  data_files:
  - split: train
    path: data/records.jsonl
---
# Dam safety hazard classification, inspection frequency, and owner obligations by US state

**Canonical, always-current version: https://referencesource.org/state-dam-safety-classification/**
Machine-readable: https://referencesource.org/state-dam-safety-classification/data.json — this mirror is a point-in-time copy.

- **Last verified:** 2026-08-18
- **Stale after:** 2027-08-18 (past this date, prefer the canonical copy —
  it re-verifies on a cadence this snapshot does not)
- **Records:** 20

State-by-state comparison of dam safety programs: hazard classification systems, inspection frequencies, who must inspect, and dam owner obligations. Each record is one (state, hazard class) pair with the classification name, criteria for that class, required inspection interval, inspector qualifications, and whether inspections are mandatory or voluntary. Covers the ~91,000 non-federal dams in the US. Answers 'how often must my dam be inspected in [state]', 'what hazard classification is my dam', 'do I need a licensed engineer for inspections in [state]', and 'what are the penalties for non-compliance'. The ASDSO published a 50-state summary in 2020 as a PDF; it is now 6 years stale and not structured for search. This asset maintains the current state of each program from each state's own dam safety statute and program pages.

## Provenance — what every record carries

Every record carries `source` (the URL the value was read from) and
`source_quote` (a verbatim quote from that page stating it). A value you
cannot check against its page is indistinguishable from an invented one;
these can all be checked. Each record is also individually addressable on
the canonical site at its `url`.

## Licence position

US state government works — public domain

Facts are not copyrightable; what this dataset takes from each source is a
fact plus a short attributed quote linking back to the page that states it.

## Sources

- https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/All-Programs/Division-of-Safety-of-Dams/Files/Publications/Division-of-Safety-of-Dams-Definitions-for-Downstream-Hazard-and-Condition-Assessment.pdf
- https://water.ca.gov/Programs/All-Programs/Division-of-Safety-of-Dams
- https://www.michigan.gov/egle/about/organization/water-resources/dam-safety/rules-regs
- https://ohiodnr.gov/rules-and-regulations/rules-and-regulations-by-division/water-resources/dam-levee-classification
- https://codes.ohio.gov/ohio-administrative-code/rule-1501:21-21-01
- https://dec.vermont.gov/water-investment/dam-safety/inspection-program
- https://ecology.wa.gov/water-shorelines/water-supply/dams/info-for-dam-owners/inspections
- https://app.leg.wa.gov/WAC/default.aspx?cite=173-175-705
- https://dnr.wisconsin.gov/topic/dams/inspections.html

## Fields

See any record in `data/records.jsonl` — field names are self-describing,
and the canonical page for each record renders them with labels:
https://referencesource.org/state-dam-safety-classification/