Algae and Cyanotoxins Resources

Last Modified: Jul 22, 2015


  • Erik Rosenfeldt, Bill Becker, Mark Bishop - Hazen and Sawyer

This wall poster can serve as a guide for monitoring and responding to harmful algal blooms and cyanotoxins in drinking water supplies.

This fact sheetoutlines the EPA-issued guidelines for preparing for algae in water supply.

The Hazen-Adams model allows utilities to estimate the amount of cyanotoxins that will be removed during oxidation by ozone, permanganate, chlorine, chlorine dioxide, or chloramine at their facility.

Water utilities are facing increased threats of harmful algal blooms (HABs) and cyanotoxins in their drinking water supplies, particularly in the summer months. Algae-related toxins may cause taste and odor issues, and more importantly, can result in shutdowns of the water system to protect public health.

A holistic approach for reducing risk from HABs and cyanotoxins considers monitoring and managing HABs in source water, and treatment barriers for algal toxins in the plant. The resources at this link can help guide your utility through the monitoring process and help you develop a response should you face an algal event.

These resources include:

A 11×17 Printable Wall Poster
This wall poster walks you through the steps involved in monitoring for – and responding to – algae events of varying severity.

Fact Sheet
This fact sheet covers the EPA guidance recommendations issued in May 2015.

Hazen-Adams CyanoTOX Model
This model, available to AWWA subscribers, calculates how various oxidants at a water treatment plant impact cyanotoxin concentrations.

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