The river is known to have toxic algal blooms with the last occurring in 2007.

Off the Japanese coast, the resulting red tides often cause disruption to fish farms, although raphidophytes are not usually responsible for toxic blooms.

The toxic blooms of blue-green algae that have caused fish kills in Connecticut occur in the summer and early fall.

Such toxic blooms are associated with warming ocean waters.

In addition to blocking salmon runs, the reservoirs that form behind the dams built up extremely high levels of toxic algal blooms.

Other groups include phytoplankton which produce the toxic algal blooms.

Some colorless dinoflagellates may also form toxic blooms, such as Pfiesteria.

They are the most common toxic cyanobacterial bloom in eutrophic freshwater.

The water is relatively nutrient rich, but it has been known to suffer from potentially toxic blooms of Blue green algae.

The lake has regularly suffered from serious toxic algal blooms since its creation.