Source: Wyoming DEQ
Cyanobacteria are microscopic, photosynthetic organisms that can be found naturally in all aquatic systems. Under certain conditions, cyanobacteria can multiply and become very abundant, discoloring the water throughout a water body or accumulating at the surface. These occurrences are known as blooms. Cyanobacteria may produce potent toxins (cyanotoxins) that pose a threat to human health. Cyanobacteria can also harm wildlife and domestic animals, aquatic ecosystems, and local economies by disrupting drinking water systems and source waters, recreational uses, commercial and recreational fishing, and property values.
This guidance is focused on strategies that you may use in response to cyanobacterial blooms that are found in freshwater aquatic environments, including lakes, streams, rivers, reservoirs, ponds, and freshwater-influenced estuaries. It is intended to help you select monitoring, excess nutrient reduction, in-lake management, and communication approaches that may be suitable for use in your water body. We provide interactive tools to help you explore options in monitoring, management, and nutrient reduction. Our Visual Guide will help you recognize cyanobacteria and other common aquatic phenomena that can be confused with them.
Together, this information, interactive tools, and embedded resources will help you respond to and manage for cyanobacteria.
ITRC has created two guidance documents, one focused primarily on planktonic HCBs, HCB-1, and the other focused primarily on benthic HCBs, HCB-2. While each document has a primary focus, each document has sections that are applicable to all HCBs, including several interactive tools. The framework shows how the two guidance documents are related and where they overlap.
Harmful Cyanobacterial Bloom (HCB) Training
The Harmful Cyanobacterial Bloom team developed an online training to accompany this guidance.
The training video below, Learn to Identify Cyanobacteria Blooms – published with help from the Lake Champlain Basin Program – identifies and describes different types of cyanobacteria and offers guidance on best management and safety practices involving harmful blooms.Published by the Interstate Technology & Regulatory Council, March 2021
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