Results of Water Tests 2020

2020

Water Quality
The ice went out of the lake in Spring 2020, in late April.
Due to the restrictions caused by the pandemic we were unable to perform the normal ice-out testing until May 19th.

Three samples were taken at each location and the test results for Total phosphorous were averaged.

The results were:

Culbute Basin – 9.0 North Basin – 9.0 ;
South Basin – 4.0 , South-east basin- 7.0 South-west basin– 4.0 .

May 29th, we completed the testing in Green Lake, taking samples at two sites.

The averaged analysis was: Site GL-01 ~ 16.0 and GL-02 ~ 19.0

Interpretation

Total Phosphorous ~ Grand Lake – while the results appear to indicate a decrease over last year, a review
of past results does show that there have been previous peaks and valleys of equivalent magnitude. But
behind occasional spikes and dips, the 20 years of data which we have indicates an upward long-term trend,
which should be the focus and concern of us all.

Green Lake – Our testing history on Green Lake has been erratic and the data is not sufficient to make any
meaningful assessment. We shall try to match Grand Lake testing frequency, but the logistics of accessing
Green Lake will require that we acquire sufficient volunteer assistance from interested Green Lake
residents.

Water clarity ~ While long-time residents often discuss the decrease in water clarity over many decades,
the Secchi Disk results have continued to be consistent with the classification OLIGOTROPHIC: “clear
water with very low levels of phosphates, algae, and nutrients.”

 

May 2020 Phosphorous Testing Sites _ GPS Waypoint coordinates

 

 

2019

The ice went out of the lake, Spring 2019, between May 1-2. Three water samples were taken at each of the five test sites on May 19th; the test results were averaged.

The results were:
Culbute Basin – 9.0; North Basin – 11.0 ; South Basin – 11.0 ; Southeast Basin – 11.0, and Southwest Basin – 5.0 .

We will test again for phosphorous in early July and September, and for
fecal coliforms in early July and mid-August

For more detail see the Spring Newsletter.

 

Previous Tests

Années/Years

2007

2008

2009

2010

2011

2012

2013

Moyenne/

Average

Lac/Lake

Achigan

3

6,3

3,3

6,3

7,3

6,0

5,4

Baie Mud

11,3

11,3

Barnes

9,2

6,6

5

11,7

9

15,7

9,5

Bataille

11

5

11,7

4,6

14

9,5

9,5

9,3

Bonin

6,5

2

4,3

Bois-Franc

5,6

2

3,8

Brassard

7

4

7,6

3,8

2,3

7

6,7

5,5

Champeau

4,7

11,7

6

6

7,7

17,3

8,9

Chevreuil

5

9

7,3

15,3

10,6

9,4

Clair

4

4,4

2

8

4,7

4,6

Corrigan

3,6

10,3

11,7

9,6

9,0

8,8

Dam

5,8

10,7

21,3

12,6

Des Chutes

18,3

18,3

Dodds

3

3,0

Écluse

3,2

3,2

Épinettes

4,3

3,6

7,3

8

8,7

6,7

6,4

Gilmour

12,1

3

8,1

8

13

35

7,7

12,4

Girard

9,3

4,5

3,3

2

12

9,0

6,7

Grand

13,6

7,6

9,2

8,3

17,3

11,5

9,5

11,0

Hardwood

2,4

2

2,7

2,3

6

8,3

5,7

4,2

Lachaine

16

16,0

Létourneau

6,7

6

6

6.2

Louise

6

3,3

3,3

9

7,3

6,7

5,9

Main

14

14,0

Marbre

3,2

4,5

4

3,3

9,3

6,5

5,1

Maskinongé

13,3

4,5

7,5

12,3

14,3

9,0

10,2

McArthur

5,7

5,7

5,6

5,5

8,3

2

7,0

5,7

McFee

5

2

2

6,6

5,1

4,5

4,2

McGlashan

5,7

4

2

3

10,7

6,7

5,3

McGregor

16,5

7,6

11,3

5,3

18

4,2

10,5

McMullin

25

18

28

23,7

McNicole

12,3

12,3

Perdrix

22

16,3

25,8

18,2

25,7

8,7

19,4

Petit Lac Clair

6

9,3

6,6

7,3

7,3

Rhéaume

16,2

13,7

7

14,7

13,1

10,8

12,6

Robinson

11

11,0

St-Antoine

10,7

13,4

12,1

St-Germain

2,7

2

2,5

2,8

7

8

6,4

4,5

St-Pierre

7,3

8,2

9,1

13

20,9

8,4

11,2

TenPenny

4,3

11,3

7

27

2,0

10,3

Truite

3,3

14,6

3,7

9,7

5,6

8,3

7,5

Twin

6,7

6,7

 Figure 1 : Phosphore des lacs en µg.L-1 (23 lacs échantillonnés en 2013