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Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep 1 , Alice Dove 2 , Todd Howell 1 and Sean Backus 2 1 Great Lakes Unit, Water Monitoring Section, Ontario Ministry of Environment & Climate Change 2 Water Quality Monitoring and Surveillance Division, Environment and Climate Change Canada PRELIMINARY FINDINGS

Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

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Page 1: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Lake St. Clair-Thames River Water Quality and

Harmful Algal Bloom Assessment

February 22, 2017

Ngan Diep1, Alice Dove2, Todd Howell1 and Sean Backus2

1 Great Lakes Unit, Water Monitoring Section, Ontario Ministry of Environment & Climate Change

2 Water Quality Monitoring and Surveillance Division, Environment and Climate Change Canada

PRELIMINARY

FINDINGS

Page 2: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Lake St. Clair-

Thames River

• Lake St. Clair is a shallow

mesotrophic lake ( < 6 m)

• Recent satellite imagery of Lake

St. Clair indicate potential wide-

spread cyanobacterial blooms

LANDSAT image of

cyanobacteria bloom in

Lake St. Clair a) July 28,

2015 (NASA/USGS;

http://landsat.usgs.gov )

2

• Thames River is the largest Canadian tributary along Lake St. Clair and is

identified as a priority tributary under Annex 4 – Nutrients of the GLWQA

• Identified a need to understand water quality conditions in Lake St. Clair

and linkage between discharges from the Thames River to lake conditions

Page 3: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Objectives

1. Assess the range of water quality

conditions in Lake St. Clair nearshore with

emphasis on the Thames River area

2. Assess the extent, occurrence,

magnitude and frequency of potential HABs

in Lake St. Clair

3. Assessment of the drivers and causal

linkages underlying water quality patterns

and cyanobacterial blooms in Lake St. Clair

4. Quantify the role of Thames River discharges on water quality conditions of

Lake St. Clair and relative contributions of nutrients and materials to Detroit River

and Lake Erie

3

Page 4: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Survey Design

To capture the key limnological features,

multiple sampling platforms were used

concurrently to track water quality conditions:

• Spatially: from Chenal Ecarte to Detroit

River, Thames River mouth to Chatham

4

• Temporally: real-time sensors deployed

across Lake St. Clair and the mouth of the Thames River to

capture water quality trends over the ice-free season

• Across habitat types: sampling across Lake St. Clair at

tributary, inshore (1 – 3 m) and nearshore (3 – 6 m) locations

• Using predictive tools: 3D hydrodynamic model to inform

survey design and future modelling of Lake St. Clair system

Maximum depth 6.4m

1 m contour 3 m contour

6 m contour

Page 5: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Hydrodynamic Modeling

– Great Lakes

Key objectives are to assess:

• the impact of key tributaries to Lake St.

Clair (discharge, movement and mixing)

• the hydrodynamic characteristics of Lake

St. Clair

• the transport of nutrients and material

from Lake St. Clair to Detroit River and

Lake Erie

Inform development survey design and

provide framework for subsequent model

applications

Modeling mesh for Lake St. Clair

3D mesh with 5 horizontal elements

• Tributaries: Thames River,

Sydenham River, Belle River,

Ruscom River

• Modeling of L St. Clair is

part of larger Great Lakes

modeling initiative

5

Page 6: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Modeling

Aug 11/07

6

Thames River Plume

Mar 29/07

• Delineated dynamic distribution of

water from each source

• Nearshore conditions can change

rapidly on daily time-scales

• Rapid displacement of water; Thames

R plume is highly dynamic

• Expected seasonal differences

• Currents are spatially differentiated

• 10 cm/s nearshore

• Upwards of 50 cm/s inshore

• ~ 75 cm/s at Thames River mouth and

head of Detroit River

Page 7: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Temporal Patterns:

Real-time Water Quality Sensors

• Water quality data logged

continuously throughout the

ice-free season (May – Nov) in

10 to 30 min increments

• 12 general monitoring areas

including the Thames River

mouth

• Parameters: current velocity and

direction, turbidity, chlorophyll a,

temperature, conductivity and

photosynthetically active radiation

(PAR)

Real-time water quality

instrumentation locations

7

Page 8: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Puce RiverDetroit R/Askins Pt

Apr

il

May

June

July

Aug

ust

Sep

tem

ber

Octob

er

Nov

embe

r

1

10

100T

urb

idity (

FT

U)

Stoney Point

Ruscom RiverBelle River

Apr

il

May

June

July

Aug

ust

Sep

tem

ber

Octob

er

Nov

embe

r

1

10

100

Tu

rbid

ity (

FT

U)

Thames River eastThames River offshoreTremblay Creek

Thames River mouth

Apr

il

May

June

July

Aug

ust

Sep

tem

ber

Octob

er

Nov

embe

r1

10

100

Tu

rbid

ity (

FT

U)

• Episodic turbidity peaks

indicative of tributary plume

waters

• Conditions highly variable in

the Thames River area and

Detroit River

• Moderate to high turbidity

across all sites

• Turbidity typically < 10 NTU

at nearshore sites

Temporal Patterns:

Real-time Turbidity

8

Page 9: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Water Quality

Surveillance

• Three sampling categories stratified by depth and water type:

• Inshore 1 – 3m depths and tributary sites (small vessel)

• Nearshore sites > 3 m depths (Guardian)

• ~ 96 stations sampled across Lake St. Clair and Thames River

• 2016 sampling events: June (inshore only), August and October

Parameters: total & dissolved phosphorus, soluble

reactive phosphorus , chlorophyll, conductivity,

chloride, phycocyanin, suspended solids,

dissolved organic carbon, sulphate, bacteriodes,

nitrogen and secchi

2016 Station Map

9

Page 10: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

• Distinctive water mass characteristics

• Inshore sites: high turbidity/suspended solids, low water clarity and higher conductivity and chloride levels

• Nearshore sites: low turbidity/suspended solids, high water clarity and low chloride levels and conductivity

Conductivity

10

SPT

- 1.7

km

SPT

- 2.4

km

SPT

- 3.5

km

SPT

- 4.4

km

SPT

- 6.6

km

SPT

- 6.9

km

SPT

- 9.2

km

200

210

220

230

240

250

260

270

Co

nd

uctivity (

uS

/cm

)

Stoney Point

Transect

Page 11: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Nutrients

• Nutrient-enriched, turbid waters with higher conductivity and chloride are indicative of tributary plume water

• Low-nutrient, clear water with low chloride and conductivity indicative of lake water

• High variability across sites and surveys

SPT -

1.7k

m

SPT -

2.4k

m

SPT -

3.5k

m

SPT -

4.4k

m

SPT -

6.6k

m

SPT -

6.9k

m

SPT -

9.2k

m

0

10

20

30

TP

(u

g/L

)

Stoney Point

Transect

11

Page 12: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

0 10 20 30 40 50 60 70 80

Total P (ug/L)

0

5

10

15

20

Ch

loro

ph

yll a

(u

g/l)

y = 0.288x – 0.642

R2 = 81%

P < 0.01

• High chlorophyll a levels inshore and in tributaries

• Moderate chlorophyll a levels offshore and near Detroit River

• Ongoing analyses on 2016 dataset

Chlorophyll a

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Page 13: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Spatial Mapping

• In situ mapping of water quality conditions concurrently with water quality sampling

• 12 mapping lines (~ 8 km) and three tracks (~35 km)

• Mapping area from 1 to 6 m depth

• Surface mapping (1 – 1.5m) and vertical profiles

• Real-time sensors: temperature, conductivity, chlorophyll a, phycocyanin and turbidity and fluorescence, dissolved oxygen

13

Page 14: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

• Distinct water mass characteristics indicative of either lake water or tributary plume waters

• High variability inshore and near the Thames River mouth area

• Strong gradients in the Thames River mouth area

Spatial Mapping

Page 15: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

• High chlorophyll a, turbidity and conductivity levels inshore and in tributaries

• Moderate chlorophyll a and turbidity levels offshore and near Detroit River

• Further integration and analyses of dataset in 2017

Spatial Mapping

Page 16: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Synopsis: An integrated WQ approach

-15 -5 5 15 25 35

Distance (km)

0

10

20

30

40

Chl

orop

hyll

a (u

g/L)

-15 -5 5 15 25 35

Distance (km)

200

300

400

500

600

700

Con

duct

ivity

(uS

/cm

)Total Dissolved P (ug/L)SRP (ug/L)

Total P (ug/L)

-15 -5 5 15 25 35

Distance (km)

0

50

100

150

200

-15 -5 5 15 25 35

Distance (km)

0

10

20

30

40

50

60

TSS

(mg/

L)

August Conductivity (Real-time)

Thames River mouth

Water Quality Samples

Page 17: Lake St. Clair-Thames River Water Quality and ... - LEMN · Lake St. Clair-Thames River Water Quality and Harmful Algal Bloom Assessment February 22, 2017 Ngan Diep1, Alice Dove2,

Summary

• Large suite of water quality data;

multiple platforms • Real-time deployed water quality sensors

• Field-based water quality surveillance and

• Spatial mapping across L St. Clair and

Thames River

• Ongoing analysis and integration of

2016 results

• 2017 field year in L St. Clair extending

into upper Detroit River with increased

sampling frequency to capture broader

range of anticipated water quality

conditions

• Opportunities for collaboration

Acknowledgements

Great Lakes Field Operations: Wendy Page, Ryan

Motostune, Brian Thorburn, Kyle McCouat, John

Thibeau, Bo Lam, Trevor Gelaznikas, Emily Peets

Water Quality Monitoring Staff: Vi Richardson, Allison

Puhl, Andrew Mummery

MOECC Laboratory Services Branch and ECCC

National Lab for Environmental Testing

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[email protected]