Harmful Algal Blooms

Harmful Algal Blooms | Wenck

Harmful Algal Blooms (HABs), are composed of photosynthesizing microorganisms called cyanobacteria that inhabit freshwater systems around the world. They can accumulate in large scums at the surface of lakes and rivers. HABs have the potential to produce toxins, and can form rapidly in warm freshwater systems posing a threat to public and ecological health.

HAB Toxins 

Currently we don’t know when cyanobacteria will produce toxins, thus cyanotoxin monitoring is necessary to protect public and ecological health!

  • Measure cyanotoxins directly – cyanobacteria biomass is an early indicator of HABs, but does not confirm that they have cyanotoxins
  • Monitor for cyanotoxins whenever you observe a cyanobacteria – HABs generate toxins at anytime in their lifecycle
  • Measure Total Cyanotoxins – cyanobacteria generate and utilize cyanotoxins inside their cells, thus measuring both cyanotoxins in the water column and within the cyanobacteria cells themselves is the most accurate way to quantify cyanotoxin potential.

How We Can Help

Risk Assessment

HABs often form in warm nutrient rich freshwater ecosystems, however, the growth and toxicity of HABs is difficult to predict. Wenck has worked on improving these predictions by investigating all aspects of the aquatic environment in which HABs form and thrive. Factors affecting HABs include a wide range of environmental conditions including: lake mixing, water temperature, stratification, and internal nutrient loading.


Wenck has experience with developing protocols for all stages of HAB monitoring including: early prediction, cyanobacteria biomass, and cyanotoxins.

Management Solutions

Once the threat of HABs has been identified, water utilities and lake managers use different technologies and treatments to mitigate the risk of HABs to the public and the freshwater ecosystems. HAB controls range in size, scope, and effectiveness dependent on the affected waterbody. Our team has experience evaluating HAB lake management strategies under different environmental and boundary conditions.

Our team has been working on lake restoration projects for over 30 years. We have received engineering and technical excellence awards for restoration projects and outstanding research in lake restoration, protection, and management.

We have experience diagnosing and implementing successful HAB controls i.e. alum treatments, dredging, circulation, and hypolimnetic aeration.


Anne Wilkinson | Wenck

Wenck Contact

Anne Wilkinson

Water Resources Engineer