National Dam Safety Program

The United States has more than 91,000 dams — from massive hydroelectric structures to small agricultural impoundments. The National Dam Safety Program, administered by FEMA in coordination with the Army Corps of Engineers and state agencies, ensures these structures are inspected, inventoried, and maintained to protect human life and property.

Current Law (2026)

Legal Authority

• 33 U.S.C. § 467 — Definitions (establishes what qualifies as a "dam" for federal safety purposes: 25+ feet high or 50+ acre-feet capacity)
• 33 U.S.C. § 467a — Inspection of dams (directs the Secretary of the Army to carry out a national inspection program; exempts dams under Bureau of Reclamation, TVA, or FERC jurisdiction)
• 33 U.S.C. § 467b — Investigation reports to Governors (requires reporting inspection findings to state governors)
• 33 U.S.C. § 467c — Determination of danger to human life and property (authorizes emergency determinations)
• 33 U.S.C. § 467d — National inventory of dams and low-head dams (requires the Army Corps to maintain a comprehensive database including location, ownership, condition, and safety status)
• 33 U.S.C. § 467e — Interagency Committee on Dam Safety (ICODS) (coordinates dam safety efforts across federal agencies)
• 33 U.S.C. § 467f — National dam safety program (establishes the coordinated program under FEMA with strategic planning, state assistance, and a National Dam Safety Review Board)
• 33 U.S.C. § 467f-1 — Lock and dam security (addresses post-9/11 security concerns at critical dam infrastructure)
• 33 U.S.C. § 467f-2 — Rehabilitation of high hazard potential dams (provides grants to states and tribes for rehabilitating dams whose failure would cause loss of life)
• 33 U.S.C. § 467g — Research (authorizes dam safety research programs)
• 33 U.S.C. § 467g-1 — Dam safety training (supports training for state dam safety staff and inspectors)
• 33 U.S.C. § 467g-2 — Public awareness and outreach for dam safety (mandates public education about dam hazards)
• 33 U.S.C. § 467j — Authorization of appropriations ($9.2 million/year through FY 2028, allocated by formula to states)
• 33 U.S.C. § 467n — Recovery of dam modification costs required for safety purposes

How It Works

The National Dam Safety Program operates as a federal-state partnership. FEMA administers the program nationally, setting standards and distributing funding, while state dam safety agencies handle on-the-ground inspections and enforcement. The Interagency Committee on Dam Safety (ICODS) coordinates across federal agencies that own or regulate dams — the Army Corps, Bureau of Reclamation, FERC, TVA, and others.

The Army Corps maintains the National Inventory of Dams (NID), which catalogs every qualifying dam in the country. A dam qualifies if it is 25 feet or taller (measured from the downstream toe) or can impound 50 or more acre-feet of water. The inventory tracks each dam's location, owner, condition, hazard classification, and inspection history. A separate provision requires tracking low-head dams — often called "drowning machines" — which pose disproportionate safety risks despite their small size.

Dams are classified by hazard potential, not structural condition. A "high hazard potential" dam is one whose failure would likely cause loss of life, regardless of the dam's current condition. This distinction matters because federal rehabilitation grants under § 467f-2 are specifically targeted at high hazard potential dams, providing funding to states and tribal governments to bring dangerous structures up to safety standards.

Federal funding flows to state programs through a formula: one-third is divided equally among qualifying states, and two-thirds is allocated proportionally based on each state's number of dams and hazard classification. States must maintain their own dam safety programs to qualify for assistance. FEMA also funds research, training for state inspectors, and public awareness campaigns about dam hazards.

The program explicitly exempts certain dams from Army Corps inspection: those regulated by the Bureau of Reclamation, TVA, FERC, or the International Boundary and Water Commission, and those recently inspected by state agencies at a governor's request. This avoids duplication while ensuring every dam has some regulatory oversight.

How It Affects You

If you're a homeowner or property owner near a dam: If you live downstream of a dam classified as high hazard potential, the dam's condition directly affects your safety and property value. Your state dam safety agency should have inspection records available, and the National Inventory of Dams is publicly searchable. Dam failure inundation maps may affect insurance requirements and property disclosures.

If you're in state or local government: States bear primary responsibility for dam safety regulation and enforcement. Federal grants through the program offset some costs, but states must maintain qualifying programs. Local governments may own dams (many small municipal water supply dams) and face inspection and maintenance obligations.

If you're a dam owner: Private dam owners — including farmers, ranchers, and developers with impoundment structures — must comply with state dam safety regulations. If your dam meets the federal threshold (25 feet or 50 acre-feet), it appears in the national inventory. Rehabilitation grants may be available if your dam is classified as high hazard potential.

If you're an infrastructure or public works planner: The aging dam portfolio is a real liability. Most U.S. dams were built between 1930 and 1980, putting tens of thousands of structures at or past their 50-year design life. The National Inventory of Dams shows more than 15,600 high hazard potential dams — structures whose failure would likely kill people — in less than satisfactory condition. Federal rehabilitation grants under § 467f-2 provide a funding pathway, but demand far exceeds available resources ($9.2 million/year in federal program funding is a rounding error relative to the rehabilitation backlog, estimated in the tens of billions). State and local dam owners should be watching for IIJA-funded rehabilitation cycles and WRDA project authorizations as funding opportunities.

Many high-hazard dams are federal reclamation facilities operated by the Bureau of Reclamation, which maintains its own safety program for the 476 dams in its portfolio.

State Variations

Dam safety regulation is primarily a state function, with wide variation in stringency:

• All 50 states have dam safety programs, but staffing and enforcement resources vary dramatically
• Some states (e.g., California, Colorado) have robust inspection regimes with dedicated engineering staff
• Other states have minimal programs with only a handful of inspectors for thousands of dams
• Hazard classification systems vary by state, though federal standards provide a baseline
• Some states require emergency action plans for high hazard dams; others make them voluntary
• Private dam owner responsibilities vary significantly — some states can compel repairs, others lack enforcement authority

Implementing Regulations

• 44 CFR Part 222 — FEMA dam safety (National Dam Safety Program, grant assistance to states, dam safety research)
• 33 CFR Part 222 — Army Corps of Engineers Engineering and Design standards, covering dam and reservoir safety engineering. Key provisions:
  • § 222.2 — Spillway land acquisition: guidance on acquiring lands downstream from spillways for hydrologic safety — protecting the public from hazards imposed by controlled or uncontrolled spillway discharges when dams must release flood waters; applicable to Civil Works projects
  • § 222.3 — Power and communication line clearances: prescribes minimum vertical clearances for power and communication lines crossing over Corps reservoir projects — ensuring that relocated or newly constructed lines maintain safe clearance above maximum pool elevations, accounting for sag, temperature variation, and ice loading
  • § 222.4 — Post-earthquake inspection and reporting: requires Corps districts to assess structural integrity and operational adequacy of major Civil Works structures following any significant earthquake in their area; establishes procedures for emergency inspections, damage reporting, and determining whether a dam or levee can safely continue operations after seismic events
  • § 222.5 — Water control management: prescribes policies for Corps water control management activities including establishment of water control plans (WCPs) for both Corps-operated and non-Corps projects in Corps watersheds; WCPs govern how reservoir pools are managed for flood control, water supply, hydropower, navigation, and recreation — the document that determines when flood gates open and how fast
  • § 222.6 — National Program for Inspection of Non-Federal Dams: implements the Corps' inspection program for non-federal (state and privately owned) dams under 33 U.S.C. § 467 — the Corps inspects high-hazard non-federal dams and reports findings to state dam safety programs and dam owners; the program does not give the Corps regulatory authority over non-federal dams but identifies deficiencies that state regulators can require owners to address

Pending Legislation

• HR 5414 (Rep. Van Drew, R-NJ) — Federal priority system for high-hazard dam rehab, extend funding through 2031. Status: In committee.

Recent Developments

• Oroville Dam (2017) remains the defining modern dam safety event: In February 2017, the main spillway of Oroville Dam — the tallest dam in the United States, operated by California's Department of Water Resources — failed catastrophically, and the emergency spillway (never previously used) also showed signs of failure. Nearly 188,000 downstream residents were evacuated. The dam hadn't failed, but it came dangerously close. The Oroville incident accelerated federal pressure on states to update inspection protocols, emergency action plans, and spillway capacity analyses for high hazard dams — particularly those with unlined or earthen emergency spillways that had never been stress-tested.
• IIJA (2021) added significant dam rehabilitation funding: The Infrastructure Investment and Jobs Act included approximately $585 million in new funding for dam safety — the largest single infusion of federal dam safety resources in decades. This included direct rehabilitation grants for high hazard dams and expanded support for state dam safety programs. While large in context, the IIJA funding covers only a fraction of the estimated rehabilitation backlog for high hazard dams nationwide.
• Climate-intensified precipitation is stressing design assumptions: Most U.S. dams were designed using historical precipitation records that did not account for the intensification of rainfall events under current climate conditions. The Probable Maximum Precipitation (PMP) values used in dam spillway design are being re-evaluated in many states. A dam that was safely designed in 1970 may be inadequate for the precipitation events that are now plausible in its watershed. Several states have initiated systematic PMP re-evaluations for high hazard dams; the results are expected to require spillway upgrades at a significant share of existing structures.
• Low-head dam inventorying expanded: Low-head dams — small structures often 3–15 feet high that span streams and rivers — are sometimes called "drowning machines" because the recirculating hydraulic currents they create trap swimmers and boaters with high lethality. Congress strengthened the National Inventory of Dams requirements to explicitly include low-head dam documentation (33 U.S.C. § 467d). Many communities and state agencies are now conducting systematic low-head dam inventories and evaluating removal or modification as a safety measure.
• FEMA budget cuts and dam safety program (2025): The National Dam Safety Program is administered by FEMA, which faced significant workforce reductions and budget pressure under the Trump administration's DOGE-driven cuts. FEMA's dam safety grant programs — funding state inspection programs and dam rehabilitation — saw proposed cuts in Trump's FY2026 budget. The dam safety grant program distributes approximately $10–12 million annually to states; even small reductions affect inspection staffing in lower-capacity state programs. Dam safety advocates, particularly those representing downstream communities near high hazard dams, have pushed back on proposed cuts given the documented inspection backlog.
• Dam removal vs. dam preservation — policy divide (2025): The Klamath River dam removal (completed 2024) — the largest dam removal in U.S. history — demonstrated the feasibility of removing aging dams for fish passage and river restoration. The Trump administration opposes most dam removal, viewing dams as water storage and hydropower assets consistent with the "energy dominance" and western water supply agenda. FEMA's dam safety program is focused on maintaining and improving existing dams rather than removal; Trump's Interior Department has specifically directed agencies to consider alternatives to dam removal when fish passage or ecosystem restoration is the goal. This creates a policy divergence: the dam safety program's rehabilitation focus aligns with the administration's dam preservation posture, while climate-driven spillway inadequacy concerns require upgrades — which are expensive but funded through IIJA grants.