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The Chemical Water Quality of Lake Nipissing 2003-2004. Andrew Paterson Dorset 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 - PowerPoint PPT Presentation
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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
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