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Harmful Algal Bloom Monitoring: Challenges and Lessons Learned
Anne Wilkinson, PhD
Wenck Associates
Colorado Lake and Reservoir Management Association Fall Meeting 2018
November 19, 2018
1
October 31, 2018
Presentation Outline
• Part 1: Introduction to Harmful Algal Bloom Risk Factors & Monitoring Strategies
• Part 2: CO Harmful Algal Bloom Monitoring and Management • Water Research Foundation Grant Overview• Common Concerns• Opportunities for Communal Resources• Lessons Learned• What’s Next?
2
Part 1:Introduction to Harmful Algal Bloom Risk Factors & Monitoring Strategies
3
Madison Lake, MN July 2016
200 μm
Freshwater microscopic photosynthetic microorganisms that have
the potential to form Harmful Algal Blooms (HAB)
4
Harmful Algal Blooms and Public Health
5
OHIO SEA GRANT AND STONE LABORATORY
Dioxin (0.000001 mg/kg-d)
Microcystin LR (0.000003 mg/kg-d)
Saxitoxin (0.000005 mg/kg-d)
PCBs (0.00002 mg/kg-d)
Cylindrospermopsin (0.00003 mg/kg-d)
Methylmercury (0.0001 mg/kg-d)
Anatoxin-A (0.0005 mg/kg-d)
DDT (0.0005 mg/kg-d)
Selenium (0.005 mg/kg-d)
Alachlor (0.01 mg/kg-d)
Cyanide (0.02 mg/kg-d)
Atrazine (0.04 mg/kg-d)
Fluoride (0.06 mg/kg-d)
Chlorine (0.1 mg/kg-d)
Aluminum (1 mg/kg-d)
Ethylene Glycol (2 mg/kg-d)
Botulinum toxin A (0.001 mg/kg-d)
Toxin Reference Doses
Toxic
ity
Neurotoxin
(nervous system)
Hepatotoxin
(liver)
Dermatoxin (skin)
Saxitoxin
Anatoxin
BMAA
Microcystin
Cylindrospermopsin
Lyngbyatoxin
Lipopolysaccharides
• Microcystin is regulated in drinking
water by the EPA and World Health
Organization
• Microcystin and other cyanotoxins
cause cancer, GI illness, and skin
rash
• Cyanotoxins present in HABs are
fatal to pets and wildlife
Possible causes of HABs
• Excess macro-nutrients-(Phosphate, Nitrate) • e.g. Paerl et al. 2016
• Excess inorganic carbon• e.g. Song et al. 2016
• Warm temperatures• e.g Elliot 2012 ;You et al. 2018
• Stable Stratification• Paerl and Huisman 2009, Visser et al. 2015
Anthropogenic Influences
Industrialized Farming
Climate Change
6
Cyanobacteria blooms and their risk factors are increasing
across the globe!
Cyanobacteria Blooms in Lakes
• Driven by codependent environmental conditions rather than a single variable
• Cyanobacteria accumulation is highly spatially and temporally transient
• Prediction and management is difficult
Beach
Madison Lake July, 2016
7
Importance of Understanding HAB Vertical Variability• Risk of drinking water
contamination is dependent on depth of intakes
• Current monitoring strategies could be underestimating HABs
• We need to understand Where, When and How much to sample to get a representative data to accurately observing HAB dynamics
Seasonal high resolution, high frequency monitoring of cyanobacteria biomass
concurrent with high resolution seasonal meteorological, temperature and water
quality data is necessary to capture complex bloom dynamics 8
Research StationMeasurements:
Meteorological Station (every 5 minutes)
- wind speed, wind direction, precipitation,
Air temperature, Ambient light
Thermistor Chain (every 5 minutes)
Water Temperature
Profiler (every 2hours; every 0.5m)
PAR penetration
pH
Dissolved oxygen
Specific Conductivity
Phycocyanin (cyanobacteria)
Water Samples (every week; every1m)
Cyanobacteria composition
Nutrients
Cyanotoxins (Total Microcystin)
9
Seasonal Water Quality Monitoring Site
2 km10.50
10
Madison Lake
South Center Lake
Nutrient Concentrations ConditionsMadison Lake
11
South Center Lake
• The nitrate+nitrite conditions were all
<0.05 mg/L during our observation
periods
• Phosphate concentrations were higher
in Madison Lake as compared to South
Center Lake
• Phosphate concentrations are high in
the epilimnion
The variability in either hypo/epilimnetic
phosphate concentrations cannot entirely
describe the variability in cyanobacteria
biovolume (BV)
BV Distribution in the water column
• During the stratified period, the
BV is accumulated above the
thermocline
• However, when the
stratification weakens the BV is
uniformly distributed
throughout the water column in
Madison Lake
We would like to describe this
vertical BV distribution.
Madison Lake
7/19/16 7/29/16 8/8/16 8/18/16 8/28/16 9/7/16 9/17/16 9/27/16
South Center Lake
2
4
6
8
z (m
)
10
8
6
4
2
(µm
3/m
L)
12
BV Heterogeneity
BV/BVave
• BVmax /BVave quantifies BV
stratification in the water
column
• Overall, Madison Lake has
lower BV heterogeneity
• BV is uniform during the
weak stratification in Madison
Lake
ML ML SC
13
BV Heterogeneity vs Thermal Structureunstable
stable
14
• Higher temperature and stratification in the water column means more stratified distribution of Cyanobacteria
• Easily measurable parameters can inform BV distribution
BV distribution above the thermocline
15
Heterogeneity in Surface Layer
• There are two distributions observed in
the BV above the thermocline
• In terms of sampling having this peak is a
problem because BV can be under-
sampled
peakuniform
16
Predicting BV distributions
• Using wind and the depth of the
surface layer we can predict when a
peak will occur.
• We the mixing is higher there is a
greater probably of uniform
distribution
17
0.0
0.5
1.0
1.5
2.0
2.5
3.0
z/z T
0.0 0.2 0.4 0.6 0.8 1.0
MC (g/L)
BV and Microcystin Distribution
• MC is higher in South Center Lake
• BV and MC are distributed above the thermocline
18
South Center Lake
Madison Lake
2.0x107
4.0x107
6.0x107
8.0x107
1.0x108
0.0
0.5
1.0
1.5
2.0
2.5
3.0
7/29/16
8/3/16
8/12/16
z/z T
BV (m3/mL)
0.0 0.2 0.4 0.6 0.8 1.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
MC (g/L)
z/z T
2.0x107
4.0x107
6.0x107
8.0x107
1.0x108
0.0
0.5
1.0
1.5
2.0
2.5
3.0
7/29/16
8/3/16
8/12/16
z/z T
BV (m3/mL)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
z/z T
2.0x107
4.0x107
6.0x107
8.0x107
1.0x108
8/11/17
6/15/17
7/21/17
8/2/17
8/4/17
8/7/17
BV (m3/mL)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
z/z T
2.0x107
4.0x107
6.0x107
8.0x107
1.0x108
8/11/17
6/15/17
7/21/17
8/2/17
8/4/17
8/7/17
BV (m3/mL)
Microcystin vs Cyanobacteria BV
• MC and BV are highly correlated
The vertical distributions of BV and MC are the statistically similar
• Still, The regression is different probably because of cyanobacteria composition
19
0 1x107
2x107
3x107
4x107
5x107
6x107
7x107
8x107
9x107
1x108
0.0
0.2
0.4
0.6
0.8MC=9.02x10
-9BV
R2=0.84
MC
(
g/L
)
BV (m3/mL)
Equation y = a + b*x
Plot MC_ave
Weight No Weighting
Intercept 0.06804 ± 0.0403
Slope 7.74662E-9 ± 9.2857E-10
Residual Sum of Squares 0.2174
Pearson's r 0.88631
R-Square(COD) 0.78555
Adj. R-Square 0.77426
MC=1.5x10-9BV
R2=0.31
Madison Lake
South Center Lake
Recommendations: Sampling Protocolk
When?: We saw BV and MC anytime from ice out to ice over Where and How many samples?:
SAMPLE
ReSL thermistor chain,
wind
StcpTs
thermistor chain
BV PROFILE
ABOVE THE THERMOCLINE
UNIFORM IN THE SURFACE
MIXING LAYER
ONE SAMPLE ANYWHERE ABOVE THE
THERMOCLINE
FORMING LOCAL PEAKS
MANY SAMPLES ABOVE THE
THERMOCLINE
UNIFORM IN THE WATER
COLUMN
ONE SAMPLE ANYWHERE IN
THE WATER COLUMN
20
Part 2: CO Harmful Algal Bloom Monitoring and Management
21
Risks of Harmful Algal Blooms in Reservoirs
• Managing HABs in reservoirs is particularly important as they serve as a drinking water source
• Cyanotoxins can be difficult to predict, detect and remove from raw water.
• Quick response is necessary to protect human health
• Frequent consistent monitoring and a response plan are necessary
22
Taste and Odor and Cyanobacteria
• Cyanobacteria can co-produce taste and odor compounds and cyanotoxins
• Cyanotoxins and taste and odor compounds do co-occur.
23
WRF grant overview
24
Goal: To provide a
critical evaluation of
sampling plans before a
bloom occurs to increase
confidence and
minimize risk of missing
something potentially
harmful.
Utility Partners
• NALMS had 10 local reservoir managers and water utilities in the Denver area
• All committed to examining HAB monitoring and Management strategies in their reservoirs
25
Common Concerns
• Sampling frequency
• Choice of data analysis
• Notification strategy
• Analysis strategy
• Management Strategies and Success
• What can I do with all this data?
• Unpreparedness or feeling behind the “curve”
• Link with Taste and Odor
26
Variety within the Partner Network
Monitoring
• Frequency
Data Analysis
• Toxins
• Cyanobacteria Biomass
Management
27
Opportunities for Communal Resources• Sampling and Monitoring Plans
• Response and Public Awareness strategies
• Recommendations for Data Analysis
• HAB Management Successes/Challenges
• Network for Equipment Training/Knowledge
• Photo Library for FlowCAM
• Sample sharing
28
Lessons Learned
29
• There has been a lot work put in to address HABs locally, across the region.
• It is now time to share our collective experiences to improve HAB monitoring and response for everyone.
What’s Next?
• Utility Partnership
• Revisit CO HAB work group
• HAB workshop/special session
30
Utah Lake, 2016 Desert News
Thank you!
3131