New Act Mandates Public Warning if Flood Control Water Exceeds 8 ppb Cyanotoxin Limit

The newly proposed Toxic Health Threat Warning Act of 2025 is pretty straightforward: it aims to stop the federal government from unknowingly flushing toxic algae water into your community. Think of it as a mandatory “Heads Up” text from Uncle Sam before he opens the floodgates.

The Mandatory Test Before the Release

Under Section 2 of this Act, the Secretary of the Army (which acts through the U.S. Army Corps of Engineers) can’t just release water from flood control structures without checking it first. They have to test the water for cyanotoxins, which are those nasty toxins produced by harmful algal blooms. These aren’t just a nuisance; they are a serious public health threat that can contaminate drinking water and make people and pets very sick. The Corps can rely on its own tests, or tests done by another federal agency or the state.

The 8 Parts-Per-Billion Trigger

Here’s where the rubber meets the road: if the testing shows the water has cyanotoxins above 8 parts-per-billion (ppb), the Corps has a mandatory public notification duty before they let the water go. This 8 ppb threshold is the key number. If you live downstream from a reservoir or flood control dam, this is the early warning system you’ve been missing. The notification must go out to the public and to any “affected government”—meaning state, local, or Tribal governments whose jurisdiction will be touched by the released water.

What This Means for Your Town

For communities located downstream, this bill is a major win for transparency and public health. Imagine a town that draws its drinking water from a river fed by a federal reservoir. Currently, a massive water release could send a toxic slug of algae downstream with little warning. Under this new Act, if that water exceeds 8 ppb, the local water treatment plant, the mayor’s office, and the public must be notified immediately. This gives them time to adjust treatment protocols, issue boil water advisories, or close off recreational areas like beaches and fishing spots before the contaminated water arrives.

On the flip side, the Army Corps of Engineers is now saddled with a new administrative load. They have to implement consistent testing procedures and ensure rapid communication across multiple jurisdictions every time a major release is planned. While this is a necessary safeguard, it adds steps to a process that often needs to be executed quickly during emergencies like heavy rain or flood events. The effectiveness of the Act will hinge entirely on the Corps’ ability to perform timely and accurate testing, and then share that data instantly with the people who need it.