This bill, known as the Toxic Health Threat Warning Act of 2025, mandates that the Secretary of the Army, acting through the Chief of Engineers, must determine if water is contaminated with cyanotoxins before any planned release from flood risk management structures. This determination will be based on tests conducted by the Secretary, another Federal agency, or the State where the structure is located. Should the water contain cyanotoxins exceeding 8 parts-per-billion , the Secretary is required to notify the public and all affected governments prior to the release. These affected governments include State, local, and Tribal jurisdictions that will be impacted. The notification must also specify the potential effects on human health from the contaminated water.