The Chemical Water Quality of Lake Nipissing 2003-2004

Andrew PatersonDorset Environmental Science Centre

Environmental Monitoring and Reporting Branch

Ontario Ministry of the Environment

Canadian Shield

Ontario’s Inland Lakes

• ~260,000 lakes

• majority on Canadian Shield

• water quality is generally good

• ↑ water quality = ↑ value

“A lake is the landscape’s most beautiful and expressive feature.It is earth’s eye; looking into which the beholder measures the depth of [his] own nature.”

- Henry David Thoreau (Walden)

• ~2 million adult anglers per year

• $1.7 billion on goods related to fishing

• residents own ~1.2 million recreational boats

• 5.6 million visitors engaged in resource-based tourism(50% participating in water sports, 39% hunting/fishing)

• $1.1 billion in spending from resource-based tourism

• commercial fisheries (~$42.5 million)

The economic value of good water quality in Ontario

(Multiple sources, 1998, 1999, 2002, 2003: Min. Natural Resources, Provincial Auditor of Ontario, Min. Tourism and Recreation)

Background

• In 2002, MOE Northern Region staff submitted a request to the Environmental Monitoring and Reporting Branch (EMRB) to undertake a water quality survey of Lake Nipissing

• Surveys had been completed in 1971, 1974 and 1975 (no summary report), and 1988, 1989 and 1990 (Neary & Clark 1992)

Background

• EMRB staff at Dorset coordinated a volunteer-based sampling program for 2003 and 2004

• Results of this survey were compiled and compared with the 1988-90 survey in a report co-authored by Clark, Paterson, DeSellas & Ingram (2010)

Clark, Paterson, DeSellas

& Ingram (2010) 57 pp.Neary & Clark (1992) 66 pp.

856

84

2

98

47

81

,42

6

88

,83

6

0

20,000

40,000

60,000

80,000

100,000

1 -

9.9

10 -

99

100

-99

9

1000

-99

99

1000

0 -

9999

9

>10

0000

Lake Area (ha)N

um

be

r o

f la

ke

s

49% 45% 5%

Lake Nipissing~82,200 ha

5

Watershed area : Lake area = ~16 : 1

Lake Nipissing and its watershed

Methods• In 2003-04 water samples were collected

from a series of 26 stations that were originally sampled in the early 1970s and again in 1988-90

• In all 3 surveys, samples were collected during the ice-free season:– in 1988-90 by a Dorset field technician monthly– in 2003-04 by volunteers on a roughly monthly

schedule (3 stations were not sampled and the other stations were sampled 5-12 times)

Lake Nipissing showing the 26 stations that were sampled in 1988-90 and re-sampled in 2003-04 (stations 2, 3 and 18 were not re-sampled). Also note that Cache Bay (#7), Callander Bay (#9) and West Bay (#19) are somewhat isolated from the main body of the lake.

Methods

Boshkung chain (1990-91)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0.0 5.0 10.0 15.0 20.0 25.0 30.0Dorset Lab TP (µg/L mean of duplicats)

Priv

ate

Lab

TP (µ

g/L

mea

n of

du

plic

ates

)

We know that the commercial lab values for total phosphorus were generally lower than the MOE Dorset lab results.

• Water chemistry from the 1970s and 1988-90 surveys was analyzed by a commercial lab

• Results from the 2003-04 survey were completed by the MOE water chemistry lab at Dorset

Methods• A number of water chemistry parameters

were measured in the 2003-04 survey including:– pH, alkalinity, aluminum, calcium (Ca),

chloride (Cl), colour, conductivity, dissolved inorganic carbon, dissolved organic carbon (DOC), iron, potassium, magnesium, manganese, sodium, ammonium (NH4), nitrate/nitrite (NO3), total Kjeldahl nitrogen (TKN), phosphorus (TP), silica, and sulphate (SO4)

Acid Rain: pH, alkalinity, sulphate

0

500

1000

1500

2000

2500

3000

1960 1965 1970 1975 1980 1985 1990 1995 2000

Year

SO

2 E

mis

sio

ns

(k

ilo

ton

ne

s)

0

500

1000

1500

2000

2500

3000

1960 1965 1970 1975 1980 1985 1990 1995 2000

Year

SO

2 E

mis

sio

ns

(k

ilo

ton

ne

s)

pH Concentration

6

7

8

9

6 7 8 9

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4

pH Cache Callander

r2 = 0.861 (Pt<0.001)

slope = 1 (P=0.865)intercept = 0 (P=0.611)

Sulphate Concentration (mg/L)

0

5

10

15

0 5 10 15

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4

SO4 Cache Callander

r2 = 0.701 (Pt<0.001)

slope = 1 (P=0.274)intercept = 0 (P=0.127)

Nutrients: Nitrogen & PhosphorusResults from a whole-lake experiment conducted at the Experimental Lakes Area, near Kenora, ON in 1973

Carbon & Nitrogen only

Barrier

Carbon, Nitrogen

& PHOSPHORUS

Phosphorus is a nutrient that is the limiting factor “controlling” algal growth in aquatic ecosystems

Phosphorus Concentration (ug/L)

0

10

20

30

40

0 10 20 30 40

Average for 1988-90

Av

era

ge

fo

r 2

00

3-0

4

TP Cache Callander

r2 = 0.635 (Pt<0.001)

slope = 1 (P=0.002)intercept = 0 (P<0.001)

Phosphorus Concentration (ug/L)

0

20

40

60

0 20 40 60

Average for 1971-75

Ave

rag

e fo

r 19

88-9

0

TP Cache Callander

r2 = 0.458 (Pt<0.001)

slope = 1 (P<0.001)intercept = 0 (P=0.008)

Phosphorus Concentration (ug/L)

0

20

40

60

0 20 40 60

Average for 1971-75

Ave

rag

e fo

r 20

03-0

4

TP Cache Callander

r2 = 0.296 (Pt<0.001)

slope = 1 (P<0.001)intercept = 0 (P<0.001)

Long-term declines in phosphorus – Dorset A lakes

Relative trends Regional trend

Ice-free year

1975 1980 1985 1990 1995 2000 2005

[TP

] -

z-sc

ore

-3

-2

-1

0

1

2

3

Blue ChalkChubCrossonDickieHarpHeneyPlasticRed Chalk (Main)

Ice-free year

1975 1980 1985 1990 1995 2000 2005

[TP

] z-

sco

re

-2

-1

0

1

2

Regional trend (6 lakes)

Average decline in TP = 28%

TKN Concentration (ug/L)

0

200

400

600

0 200 400 600

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4

TKN Cache Callander

r2 = 0.520 (Pt=0.144)

slope = 1 (P=0.058)intercept = 0 (P=0.118)

NH4 Concentration (ug/L)

0

30

60

90

0 30 60 90

Average for 1988-90

Av

era

ge

fo

r 2

00

3-0

4

NH4CacheCallander

r2 = 0.211 (Pt<0.001)

slope = 1 (P=0.014)intercept = 0 (P<0.001)

Nitrate/Nitrite Concentration (ug/L)

0

40

80

120

0 40 80 120

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4

NO3CacheCallander

r2 = 0.213 (Pt<0.001)

slope = 1 (P=0.541)intercept = 0 (P=0.148)

r2 = 0.213 (Pt<0.001)

slope = 1 (P=0.541)intercept = 0 (P=0.148)

Large increases in nitrate between 1988-90 and 2003-04

Seasonal nitrate in Callander Bay

0

50

100

150

200

Nit

rate

/nit

rite

co

nce

ntr

atio

n ( g

·L-1

)

0

50

100

150

200

Day of year

100 150 200 250 300 3500

50

100

150

200

0

200

600

800

Day of year

100 150 200 250 300 350

Nitrate/n

itrite con

centratio

n (

g·L

-1)

0

50

100

150

200

1988

1989

1990

2003

2004

Other interesting results

• Is road salt affecting the lake?

• Is dissolved organic carbon (DOC) changing?

• Are calcium concentrations changing?

Chloride Concentration (mg/L)

0

1

2

3

4

5

6

7

0 1 2 3 4 5 6 7

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4Cl Cache Callander

r2 = 0.810 (Pt<0.001)

slope = 1 (P=0.525)intercept = 0 (P=0.006)

DOC Concentration (mg/L)

0

2

4

6

8

10

0 2 4 6 8 10

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4

DOC Cache Callander

r2 = 0.621 (Pt=0.800)

slope = 1 (P=0.008)intercept = 0 (P=0.010)

Calcium Concentration (mg/L)

0

5

10

15

20

0 5 10 15 20

Average for 1988-90

Ave

rag

e fo

r 20

03-0

4

Ca Cache Callander

r2 = 0.953 (Pt<0.001)

slope = 1 (P=0.002)intercept = 0 (P=0.105)

Are the Lake Nipissing biota healthy?Mercury in 35-45cm Walleye from Lake Nipissing

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

1976 1977 1985 1989 1990 1998 2002 2003 2009

Mea

n M

ercu

ry (

ug

/g)

± st

and

ard

dev

iati

on N Ontario lakes

mean = 0.5 ug/g

Summary

• Acid rain: both pH and sulphate (SO4) concentration have decreased

• Nutrients: – Total Kjeldahl nitrogen (TKN) has not

changed, but nitrate/nitrite (NO3) and ammonium (NH4) have increased

– Total phosphorus (TP) has increased, but this may be a lab artefact (levels are lower than the 1970s)

Summary

• Other parameters:– Chloride (Cl) has increased– Dissolved Organic Carbon (DOC) has not

changed– Calcium (Ca) has decreased

Thank You

Are there any questions?

MOE – North Bay Office

• District staff proactively inspect municipal STPs to ensure compliance with MOE issued Certificates of Approval. The district also inspects large sub-surface sewage systems that have a flow rate of >10,000 LPD (usually associated with resorts).

• District staff conduct comprehensive inspections of hazardous waste generators, waste sites and industrial air dischargers, water users taking >50,000 LPD – all to ensure compliance with MOE issued approvals and permits.

MOE – North Bay Office

• District Environmental Officers respond to spills and other environmental incidents to ensure proper clean-up and compliance with Ontario’s environmental legislation such as the Environmental Protection Act, Ontario Water Resources Act, Pesticides Act.

• District staff also conduct initial sampling for suspected Blue Green Algae complaints and forward results to the local Health unit for follow up action (if positive)

MOE – North Bay Office

• District staff conduct spring phosphorus sampling and in some cases dissolved oxygen surveys.

• MOE also operates a 24 hour spill reporting center – 1-800-268-6060

Nitrogen Components

TN = TKN + NO3 = TIN + TON

TKN = TON + NH4

TON = TN – (NO3 + NH4) = TKN – NH4

TIN = NO3 + NH4

Observed Changes over TimeParameter

(units)

Meana

1988-90

Meanb

2003-04

Difference

(b-a)/a x 100

pH 7.43 7.21 -3.08*

SO4 (mg/L) 10.30 6.86 -33.41*

TKN (ug/L) 352.40 334.72 -5.03

NO3 (ug/L) 20.93 47.45 126.68*

NH4 (ug/L) 24.76 38.49 55.46*

TP (ug/L) 15.12 18.23 20.54*

Cl (mg/L) 3.38 4.22 24.81*

DOC (mg/L) 5.71 5.68 -0.61

Ca (mg/L) 7.74 7.13 -7.87*

* - significant difference at P<0.05