Blue-Green Algae Found in Lake Nipissing and the French River

September 2012

The following is a summary of several technical articles written about blue-green algae. We have tried to provide a less technical version of these reports and have only referred to the types of blue-green that we have actually found in our waterways. Where appropriate we have noted our actual experiences with blue-green algae.

What are blue-green algae?

Blue green algae are referred to as “Cyanobacteria” and are a group of photosynthetic bacteria. As you may have guessed by now they really are not algae but rather bacteria which looks like algae. Blue-green algae, like true algae, make up a portion of the phytoplankton in our water. Blue-green algae are generally not eaten by other aquatic organisms however fish swimming in affected waters can ingest them. The most common forms that are found in our waters are Anabaena, Aphanizomenon and Microcystin.

Where do blue-green algae live?

They generally grow in shallow warm bays where the water is warm, slow moving and has enriched nutrient loading primarily from phosphorus. Blue-green algae are buoyant and blooms normally result from them floating to the surface. Although somewhat weather dependant, the blooms in our water systems normally start in late summer and last until early fall. Our water sampling project has identified high levels of phosphorus loading as a major issue of concern.

How can I tell if the algae I see in my water is blue-green?

The identification of blue-green algae requires detailed lab analysis and reports of suspected blue-green algae blooms should always be called in to the Ministry of the Environment for a site visit and follow-up as sampling and testing may be required.

A characteristic of blue green algae is that it has mastered buoyancy, meaning it can raise and lower itself in water which allows it to get to the sunlight it needs for photosynthesis. They can also suspend themselves at various depths depending on the light and the nutrients available at any given water depth.

It is this ability which makes blooms seem to appear over night and then disappear as the day moves into late afternoon, only to reappear the next morning.

Waters containing near bloom levels of blue-green algae often seem to have a light green color. As conditions permit, blue-green densities increase and blooms may form. We have provided some pictures of actual blooms found in our waters but caution you that confirmation of a blue-green algal bloom requires a trained eye and scientific analysis.

What are the concerns associated with blue-green?

Concerns include discolored water, reduced light penetration, taste and odor problems. Dissolved oxygen depletion and toxin production occurs during the end of their life cycle or die off events. These concerns may be detrimental to aquatic life forms and eventually to native fish populations. More serious concerns arise when toxins, known as microcystins are produced. The World Health Organization puts the safe level for drinking water at 1.0 ug/L or one part per billion. TheOntariodrinking water standard is 1.5 ug/L. Precautions for pets, farm animals and humans are required so please visit our local Sudbury District Health Unit website which has issued appropriate advisories. Their site will help you to more clearly understand the concerns and recommended safety measures you should take when blue-green is suspected in your water.

What actually causes the blue-green algae problem? 

As was noted earlier in our summary nutrient loading is a concern, primarily phosphorus and nitrogen. Our sampling has tracked total phosphorus levels along the entire length of theFrenchRiverand the surrounding water shed. We track total phosphorus concentration through the Ministry of Environment’s Lake Partners Program. The results have shown total phosphorus concentrations to be the main concern. To blue-green algae, phosphorus is their main food and when it is a higher level blue-green can multiply quickly.

Blue-green algae have been around for a very long time and their toxic effects to livestock are well documented. Their increase can almost certainly be contributed to human activity such as the discharge of untreated or improperly treated sewage, agricultural activities, logging, the use of phosphorus based fertilizers and detergents, and unplanned unchecked shoreline development.

What can be done to reduce the frequency and intensity of blue-green algae blooms?

There are no quick or easy remedies for the control of blue-green but by reducing the amount of nutrients that enter our water system we will eventually reduce the frequency and intensity of blue-green algae blooms.

What does sampling and testing suggest are the priorities for reducing nutrient loading?

  • Some of the most severe cases of blue-green blooms show up inCallanderBay,WoseleyBayand the West Arm areas. These also happened to be the bodies of water that receive the discharges from sewage treatment lagoons. We see improving the operation of sewage lagoons as a first priority.
  • Agricultural activities involving manure handling practices, ditch clearing and logging practices that disturb the topsoil will allow rain to wash phosphorus containing soil and feces into the waterways.
  • The proper installation and maintenance of private and commercial septic systems is of a concern as the practices that were acceptable 50 years ago, when fewer folks lived along the waterway, are no longer acceptable today.

What is the French River Stewardship Council doing?

  • The FRSC has focused on working with local Municipalities and the Ministry of the Environment to significantly improve the operation of sewage lagoons. Often the first step is to educate local council and residents of the issue.
  • In areas where farming can impact nutrient loading local farmers are taking an active role with assistance from the Ministry of Agriculture to resolve concerns.
  • With respect to private and commercial systems we have had regular public meetings and presentations by experts in the field with the emphasis on education and understanding of the importance of proper system installation and maintenance. We are also asking Municipalities to review bylaws aimed at bringing systems up to standard over time.

What can I do?

 As members of our community;

  • We can all help by using phosphate free soaps, detergents and cleaning products in our households.
  • Avoid overloading septic handling systems by ensuring water infiltration such as rain runoff is directed to storm sewers and not sanitary sewage systems.
  • Ensure your septic system is properly maintained and in good operating condition.

For those of us living along our shorelines;

  • We can ensure that our septic and grey water systems are properly collected and treated and that our septic systems are properly maintained.
  • Allow native plants to remain along our shoreline or plant more of our native species there.
  • We can use compost material instead of nitrogen and phosphorus containing fertilizers to provide food to our gardens and lawns.

Most importantly we must begin now.

Date Added: September 23, 2012 | Comments Off | Filed under: News — Tags: — webedit @ 8:33 pm

Lake Winnipeg Blue Green Algae a lesson we need to learn

(Summary of a MacLean’s Magazine article Aug. 24th. 2009 edition).

Lake Winnipeg is an isolated prairie lake surrounded by forest and tucked away from industry and major population centers, yet it is dying. What was a small patch of algae, first noted in the early 1990’s has now grown to cover one half of the lakes 24,500 square kilometer area throughout most of the summer months. The green mat that covers the lake is twice the size of PEI and clearly visible from space.

The culprit is not global warming, oil spills, toxic or industrial waste but is nutrient overloading from fertilizers, human and animal waste.

Nutrients such as nitrogen and phosphorus do precisely in water what they do on land. They cause plant life to grow. This growth process is accelerated by tiling of farm land and clearing of ditches to allow runoff from fields. It comes from improperly operated and maintained sewage systems be they sewage treatment plants, sewage treatment lagoons or even home septic systems.

At the same time the destruction of wetlands and river bank areas, which are natures kidneys, has decreased these natural filters and nutrient traps by up to 70%. 

Although, nutrient loading is good to a point, there is a tipping point. When the organic material from excess weed growth dies over the fall and winter months it consumes oxygen and sinks to the bottom. It is during this period that bacteria go on an eating binge and consume oxygen and will eventually consume much of the available oxygen.

In the bottom sludge anaerobic bacteria which do not need oxygen begin to thrive and actually begin to generate their own phosphorus. Once this starts the food change in the lake will die from the bottom up.

Date Added: | Comments Off | Filed under: News — Tags: — webedit @ 8:27 pm