Black 3.5, Boyd 4.8, Curran 4.0, Clear 3.3

No, these numbers are not the results of a competition!

They are the average amount of phosphorus that was measured last summer in each of our lakes. We are talking here of micrograms per litre. Phosphorus is the main indicator of a lake’s health. These numbers are those of very healthy lakes. The government’s lab has reviewed and improved its methods and processes so that these numbers now look credible

Boyd is bit higher mostly because it’s turnover, or replenishment rate, is so rapid. About 6 months compared to around 2 years in most other lakes. Some phosphorus just does not have time to settle at the bottom of the lake. The turnover is very quick because there is such a large amount of  water coming from Black lake.

Rainbow on Black by John Parsons

For those who are new to this, we take water samples in all four lakes three times during the summer to measure phosphorus, chlorophyll and dissolved carbon oxygen (coloration). Just as important, clarity is measured ten times during that period.

Secchi Disc

This information is aggregated in charts produced by the biologists of the Department of the Environment.

Lakes are classified into four broad categories. Click on the name of the lakes to view the charts.


1. Ultra- oligotrophic (super) Both Clear and Black are in that category.

2. Oligotrophic (very good), Curran and Boyd but very close to category 1.

3. Mesotrophic  (worrying)

4. Eutrophic  (help!)

To recap. We are blessed with a very favourable environment – no agriculture, no motor boats, etc. – residents behave very responsibly and no major development project is planned in our watershed. Do make sure your septic system is in top shape, eliminate sources of run off, preserve  your shoreline protection band and make sure that boats and equipment that have been used outside of our watershed are thoroughly washed before their use  in one of our lakes. Eurasian watermill foil can devastate a lake. If you need convincing, go to the Lac des Plages, one and a half hour from here (113 kilometres).

As you probably suspect, collecting these water samples and making sure they reach the lab in due time, measuring transparency and managing that program requires team work. Sheryl Caron takes care of Curran lake, Lois and Jim Finch do the same for Black,  Rick Havill and Bonnie Swaine do Boyd, and Clear is the domain of François Côté and Simon Octeau. France and I train the volunteers and manage the program and evangelize.

Thanks are in order for our dedicated lake volunteers.

10 thoughts on “Black 3.5, Boyd 4.8, Curran 4.0, Clear 3.3

  1. Kathleen Hoelscher

    Thanks to all of you who collect the samples and also all of you residents who keep the lakes healthy.

  2. Nancy

    So good to hear. Thank you to all the volunteers who do this work on our behalf. Looking forward to a good summer!

  3. Cathy Riviere

    Thank you to one and all who are involved, we really appreciated all your work and effort.

  4. John Parsons

    Dunany is a wonderful community… steeped in history and dedicated to our future.
    Thanks to all…

  5. Trudy Adams

    Awesome! Hopefully it warms up a little so we can eventually swim and play in these pristine lakes!