The document discusses harmful algal blooms in Lake Erie that have increased in recent decades. It finds that while conservation efforts reduced sediment and particulate phosphorus runoff, they may have unintentionally increased dissolved phosphorus exports from agricultural lands via tile drainage systems. Studies show tile drainage can transport over half the dissolved phosphorus during rainstorms. The document examines long-term nutrient monitoring data and suggests better communication is needed to address misconceptions and expedite solutions to reduce phosphorus loading to Lake Erie.

1. Weak links in communication
contribute to harmful algal
blooms in Lake Erie
Laura Johnson, Rem Confesor,
Dave Baker, Ken Krieger

2. Algal blooms in Lake Erie have been
increasing
May 2013 issue of National Geographic
2011 harmful algal bloom
6 largest algal blooms since
mid-1990s have occurred
over the past 7 years
Primarily Microcystis aeruginosa
Ohio P
Taskforce 1
Toxins from the 2014 bloom
shut down Toledo’s (pop
400,000) drinking water

3. 2015 Seasonal HAB forecast

4. Current 2015 bloom on July 24
Photo: Darren Bade

5. Why are algal blooms returning to
Lake Erie?

6. Heidelberg Tributary Loading Program

7. • Samples collected 3x a day
• Analyzed for all major nutrients and
suspended sediments
Colorimetry for TP, DRP, TKN,
NH4, Si
Ion chromatography for
NO3, NO2, Cl, Fl, SO4
Suspended Sediments

8. Long-term trends in
discharge and phosphorus

9. Annual discharge
• 5 year running
average shows a
marked increase
since 2000
1975 1980 1985 1990 1995 2000 2005 2010
AnnualDischarge(km
3
)
0
2
4
6
8
10
Maumee River
1975 1980 1985 1990 1995 2000 2005 2010
0.0
0.5
1.0
1.5
2.0
2.5
Sandusky River
1975 1980 1985 1990 1995 2000 2005 2010
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Cuyahoga River

10. 1975 1980 1985 1990 1995 2000 2005 2010
0.0
0.2
0.4
0.6
0.8
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0.0
0.2
0.4
0.6
0.8
1975 1980 1985 1990 1995 2000 2005 2010
0.0
0.2
0.4
0.6
0.8
1975 1980 1985 1990 1995 2000 2005 2010
0
200
400
600
800
1000
Sandusky River
r2 = 0.02
P = 0.40
r2 = 0.04
P = 0.29
r2 = 0.02
P = 0.37
Annual total particulate P
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
1000
2000
3000
4000
Maumee River
r2 = 0.25
P = 0.002
r2 = 0.20
P = 0.01
1975 1980 1985 1990 1995 2000 2005 2010
0
100
200
300
400
500
600
Cuyahoga River
5 yr
runnin
g
mean
LOAD CONCENTRATION

11. Suspended
Sediments
• Sediments suspended in
the water has decreased!
• Patterns are more
apparent when corrected
for weather variability
1975 1980 1985 1990 1995 2000 2005 2010
TSSload(1000metrictons)
0
500
1000
1500
2000
2500
1975 1980 1985 1990 1995 2000 2005 2010
TSSFWMC(mg/L)
0
100
200
300
400
500
1975 1980 1985 1990 1995 2000 2005 2010
0
2
(1000metrictons)
300
400
500
600
700
1975 1980 1985 1990 1995 2000 2005 2010
TSSFWMC(mg/L)
0
100
200
300
400
500
600
1975 1980 1985 1990 1995 2000 2005 2010
Discharge(km3
)
0.0
0.5
1.0
1.5
2.0
2.5
r2=0.11, p=0.04
r2=0.24, p=0.003
Maumee
Sandusky
CONCENTRATION
Richards et al., 2009 JSWC

12. 1975 1980 1985 1990 1995 2000 2005 2010
0
50
100
150
200
250
Sandusky River
r2
=0.45
P<0.001
1975 1980 1985 1990 1995 2000 2005 2010
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
200
400
600
800
1000
Maumee River
r2
=0.35
P<0.001
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
1975 1980 1985 1990 1995 2000 2005 2010
0
20
40
60
80
100
120
Cuyahoga River
1975 1980 1985 1990 1995 2000 2005 2010
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
Annual dissolved P
LOAD CONCENTRATION

13. Why did dissolved
phosphorus increase?

15. Average soil test P (Mehlich 3 P)
• Over 1500 farms
sampled
throughout the
Sandusky River
Basin
• Most farms within
the maintenance
range
• Only 10% of the
farms were above
71ppm
• P has accumulated
on the surface

16. Evidence of macropore tile drain flow
Photos: Kevin King, USDA-ARS Edge of Field Research

17. Evidence of macropore tile drain flow
Data from Doug Smith, USDA-ARS
St. Joseph River watershed
14 May 2011
• Tile drain flow peaked with surface flow at in a May 2011 storm
• Data from Kevin King, USDA-ARS around the basin shows 50-80% of the dissolved P
loading is from tile drains
Smith et al. 2014, JEQ

18. Intense precipitation (2”+) is increasing
8 Events in 16 Years!
20 Events in 16 Years
Data from Kevin King, USDA-ARS

19. 




20. Common misconceptions

21. Found in Media
• Tile drains do not deliver
phosphorus
– Article in Journal Sentinel
• Filter strips help with dissolved
phosphorus
– Former Ohio Representative Chris
Redfern
– Pennsylvania NPR
• Combined sewage overflows
contribute a majority of the
phosphorus
– Toledo Blade
• Farmers are carelessly over
applying fertilizer, applications rates
have increased

22. Weak links in communication
contribute to harmful algal blooms
in Lake Erie
• Concern over the link between increasing dissolved
P exports and HABs in Lake Erie have been
discussed since 2007
• Studies in the 1970s showed P loss in tile drains
• A report in 1980 warned of the potential tradeoffs in
the Lake Erie watershed of switching to
conservation no till
• Yet misconceptions on P runoff are still prevalent
• How can we expect a solution?

23. How can we expedite knowledge transfer?
Can we make progress without a disaster?
• WLEB 4R retailer certification program
– 16 certified nutrient service providers that cover ~1000 farmers,
50 applications, nearly 10% of the basin covered already
• Ohio fertilizer application training
– Required for all who apply nutrients to over 50 acres
– 6586 people have attended training sessions since last fall
• WLEB tri-state RCPP
– $17.5 million to the WLEB for incentives
• County SWCDs and NRCS
• Webpages
– LakeErieAlgae.com just launched
• Field days, lab tours, media interviews

24. Questions?
For more information visit:
http://www.heidelberg.edu/NCWQR
Or contact me at ljohnson@heidelberg.edu
http://www.facebook.com/NCWQR

25. Maumee
River
spring
2015

26. Annual nitrate-N
Nitrate-N
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
2
4
6
8
10
Total Kjeldahl Nitrogen
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
1
2
3
Annual Nitrate-N Load
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
20000
40000
60000
AnnualDischarge(10
6
m
3
)
0
2000
4000
6000
8000
10000
12000
Load
Discharge
Annual Total Kjeldahl Nitrogen Load
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
5000
10000
15000
20000
AnnualDischarge(10
6
m
3
)
0
2000
4000
6000
8000
10000
12000
Load
Discharge
5y running
average
Nitrate-N
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
2
4
6
8
10
12
Annual Nitrate-N Load
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
2000
4000
6000
8000
10000
AnnualDischarge(10
6
m
3
)
0
500
1000
1500
2000
2500
LOAD CONCENTRATION
MAUMEE
SANDUSKY

27. Nitrate-N
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
2
4
6
8
10
Total Kjeldahl Nitrogen
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
1
2
3
Annual Nitrate-N Load
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
20000
40000
60000
AnnualDischarge(10
6
m
3
)
0
2000
4000
6000
8000
10000
12000
Load
Discharge
Annual Total Kjeldahl Nitrogen Load
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
5000
10000
15000
20000
AnnualDischarge(10
6
m
3
)
0
2000
4000
6000
8000
10000
12000
Load
Discharge
Nitrate-N
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
2
4
6
8
10
12
Annual Nitrate-N Load
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualLoad(metrictons)
0
2000
4000
6000
8000
10000
AnnualDischarge(10
6
m
3
)
0
500
1000
1500
2000
2500
Nitrate-N
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
2
4
6
8
10
r2=0.387,P=0.004,m=-0.16
Nitrate-N
Annual Flow-Weighted Mean Concentration
Water Year
1975 1980 1985 1990 1995 2000 2005 2010
AnnualFWMC(mg/L)
0
2
4
6
8
10
12
r2=0.391,P=0.004,m=-0.18
Annual nitrate-N
LOAD CONCENTRATION
MAUMEE
SANDUSKY

28. Toledo drinking water crisis
• Over 400,000 people had no drinking water for 3 days (Aug 4-6)
• Microcystin toxin was above World Health Organization’s limit of 1 mg/L
31 July 2014 3 Aug 2014

29. • Journal Sentinel http://www.jsonline.com/news/wisconsin/toxi
c-algae-cocktail-brews-in-lake-erie-
b99344890z1-274542731.html
Journal Sentinel
Thorbahn says the pipe he's laying actually
alleviates the phosphorus problem because it
allows water that hits the crops to first be
filtered through the soil. He says water coming
straight off the surface of the fields, instead of
flowing down to the tiles, is more likely to be
contaminated with excess fertilizer
"It's surface runoff," he says, referring to how
agriculture contributes to the phosphorus
problem in the lake. "It's not the tile system."
tp://www.alleghenyfront.org/story/ohio-
rmers-point-algae-law-loophole
he Allegheny Front, Radio show
ouncing along the edge of head-high corn
elds in an electric golf cart, 65-year-old,
urth-generation Ohio farmer Roger Wise is
howing off grass-covered filter strips that
ind for miles along Wolf Creek, a small
ibutary of the Sandusky River less than 10
iles from Lake Erie.
We have a buffer between the corn and the
ick over there," says Wise. "There's a lot of
ildlife back here. It's primarily wildlife and
ater retention and conservation.
http://www.toled
076/sewage-over
can-intensify-alga
WTOL August 201
A gentle rain wou
it has been very d
had creates sewa
Erie Waterkeeper
http://
08/338
ohio-fa

30. Harmful algal blooms (HABs) in the western Lake Erie basin (WLEB) garnered national
attention in August 2014 when microcystin toxins exceeded World Health Organization limits in
Toledo’s drinking water resulting in a 3-day ban on drinking tap water. Yet the recurrence of
HABs in the WLEB have been an on-going problem for many years– the first Ohio Lake Erie
Phosphorus Task Force was formed in 2007. Increases in HAB intensity and extent over the
past decade correspond closely to increasing dissolved phosphorus (DP) loads to Lake Erie
from the agricultural Maumee River. The uptick in DP exports followed a period of intense land
management change in the 1980s aimed at reducing soil erosion through conservation tillage
and reserves. While this program succeeded in decreasing both suspended sediment and
particulate P concentrations in the Maumee River, it encouraged use of broadcast P fertilizer
and enhanced soil P stratification. Thus, increased DP runoff is the product of these unintended
consequences in combination with intensified subsurface drainage installation, increased soil
compaction, and increasing extreme spring weather events. Although other sources
(wastewater inputs, residential fertilizer use, failing septic tanks) are acknowledged as minor
contributors of P, producers are largely blamed for the events in Toledo. Based on the media
coverage following Toledo’s drinking water incident, there appears to be a knowledge gap
among producers regarding how and what form of P is entering Lake Erie, which influences
how producers reduce P loss. Thus the current state of the lake is partly due to weak or slow
communication among researchers/educators and the agricultural community. Our biggest
challenge is to better disseminate accurate information to the agricultural community that
results in implementation of practices focused on DP runoff and to foster flexibility in adopting
new practices as our understanding improves or the pollutant of concern evolves.