Wright State University's Dr. Stephen Jaquemin presented an update on the constructed wetlands at Grand Lake St. Marys at the December 2017 Lake Improvement Association member meeting. Watch the video here: https://lakeimprovement.com/video-december-2017-lia-member-meeting/

1. IMPROVING WATER QUALITY OF GRAND LAKE
ST. MARYS USING RECONSTRUCTED WETLANDS
STEPHEN J. JACQUEMIN1
, THERESA A. DIRKSEN2
, PHILLIP POORE1
, NICHOLE
MAZZONE1
, TIFFANY RICKETTS1
, NICHOLAS GNAU1
1
WRIGHT STATE UNIVERSITY – LAKE CAMPUS, AGRICULTURAL AND WATER QUALITY
EDUCATIONAL CENTER
2
MERCER COUNTY COMMUNITY AND ECONOMIC DEVELOPMENT OFFICE, AGRICULTURAL
SOLUTIONS

2. Grand Lake St. Marys Watershed
• Social, economic, and environmental value
• Mercer / Auglaize Counties (241 km2
~60,000
acre area)
• Series of 1st
/2nd
order tributaries drain into
GLSM reservoir
• GLSM constructed 1837-1845
– large (52 km2), shallow (~1.5m), and
mixed (15+km fetch wave length)
• Declines in water quality linked with long
term nutrient rich runoff – exacerbated by
physical characteristics

3. Grand Lake St. Marys Watershed
• Watershed experiences internal and external
loading
– Primarily from nutrient rich agricultural runoff
– 80-90% row crop and livestock operations
– Among highest animal concentrations in state
– Among highest soil test P levels in Ohio
– Nutrient loading is fed by external streams in winter/
spring and internal sediments during summer/fall
– EPA has listed basin and tributaries among highest
nutrient concentrations in the country
• Streams in ~75+ percentile (TMDL load reductions of >80% needed)
• Lake in ~90+ percentile for nutrients and 99th
for harmful algae blooms
• Distressed Watershed Designation in 2011
• Region has become a focal area for water quality
study and improved understanding

4. Watershed Efforts
• GLSM watershed efforts highlight the implementation of innovative combinations of
BMPs, regulations, and conservation practices to reduce nutrient runoff
– Local collaborative groups such as Ag Solutions to bring everyone together and encourage
collaboration and communication
– Nutrient management plans (Over 90% of acres are under plans) informed by soil testing
– Winter manure ban (bans manure application Dec. 15 to Mar. 1)
– Manure storage structures (~80 constructed from 2010 to 2013)
– Manure transfers (90+% of chicken litter is exported)
– Cover crops
– Edge of field runoff practices (retention ponds, saturated buffers, tile bioreactors, blind inlets)
– New manure dewatering technologies
– Constructed wetlands
• All practices must be studied and documented to provide potential future template for
management strategies

5. Why Wetlands?
• Wetlands are a natural part of any watershed
• Wetlands provide numerous ecosystem services
– Increased variety of habitat for wildlife and biodiversity maintenance
– Act as groundwater recharge points
– Store carbon
– Erosion and flood control points
– Recreation
– Improve water quality by filtering nutrients
• Historically, GLSM was dotted with numerous wetlands
• Drainage of these actually left the rich soils we depend on for agriculture
• However, devoid of natural wetlands, heavy nutrient loads from application has facilitated
degraded water quality region wide
Note: To maximize ecological services /
benefits, healthy wetland(s) need to be ~ 1-
5% of the total watershed area

6. How Do Wetlands Work?
Mechanisms of Action
Physical, chemical, and biological processes
Particulate settling (sedimentation)
Volatilization (gas into atmosphere)
Sorption (ads – solid adherence; abs – diffusing)
Transformation (uptake by plants, algae, bacteria)

7. Implementation in GLSM
• GLSM Wetlands follow a basic design:
• Prairie Creek constructed in 2012
– ~ 1% watershed area (0.05 mi2
)
• Coldwater Creek constructed in 2015
– ~ 0.2% watershed area (0.04 mi2
)
• Wetlands take time to develop as soils
and plants mature/take root
• Efficiencies can vary with season, time,
temperature, flow, residence time –
note that P is expected to primarily
adhere to soils and can reverse in fall
• There is no set recipe– emphasizes the
need for continual monitoring and
assessment moving forward
Primary Deep
Water Settling
Cell
Secondary Mid-
Water Settling Cell
Shallow Water
Vegetative Cells
Outflow
Shallow Water
Vegetative Cells
Shallow Water
Vegetative Cells
Stream Inflow

8. GLSM Constructed Wetlands
• Prairie Creek constructed in 2012
– ~ 1% watershed area (0.05 mi2
)
– Fed via a pump connected to P.C. – rated
(average) at ~1 million gallons per day
– Comprised of east and west series of cells –
flow is split between them – 2 in/outflows
– Flows from P.C. to GLSM
– Flow is controlled via pump and control boxes
• Coldwater Creek constructed in 2015
– ~ 0.2% watershed area (0.04 mi2
)
– Fed via a pump connected to C.C. – rated
(average) at ~2.5 million gallons per day
– Comprised of east and west series of cells
with combined pump inflow and outflow
– Flows from C.C. to Grassy Ck. To GLSM
– Flow is controlled via pump and control boxes

9. Research Objective
• Primary: Assess sediment and nutrient levels of GLSM constructed
wetland inflow and outflow points to evaluate concentration reductions
• Secondary: Detail stream and wetland discharge to assess capability

10. Stream Flow Summary
121110987654321
30000000
15000000
0
Month
ChickasawCreekGPD
121110987654321
10000000
5000000
0
Month
PrairieCreekGPD
121110987654321
40000000
20000000
0
Month
ColdwaterCreekGPD

11. Discharge Summary
11/1/201710/1/20179/1/2017
800000
600000
400000
200000
0
Date
PrairieCreekTTDischargeGPD
11/1/201710/1/20179/1/2017
3000000
2000000
1000000
0
Date
ColdwaterTTDischargeGPD

12. Nitrate Summary

13. Nitrate
FallSummer
PC WestPC EastPC InflowCC OutflowCC InflowPC WestPC EastPC InflowCC OutflowCC Inflow
16
8
0
NO3(mg/L)
PC West Discharge GPDPC East Discharge GPDColdwater Discharge GPD
FallSummerFallSummerFallSummer
2000000
1000000
0
Discharge(GPD)
PC W EfficiencyPC E EfficiencyCC Efficiency
FallSummerFallSummerFallSummer
0.8
0.4
0.0
NO3Removal(Percent)
PC W MagnitudePC E MagnitudeCC Magnitude
FallSummerFallSummerFallSummer
3.0
1.5
0.0
NO3Removal(Mean)

14. Total Phosphorus Summary

15. Total Phosphorus
FallSummer
PC WestPC EastPC InflowCC OutflowCC InflowPC WestPC EastPC InflowCC OutflowCC Inflow
5.0
2.5
0.0
TP(mg/L)
PC West Discharge GPDPC East Discharge GPDColdwater Discharge GPD
FallSummerFallSummerFallSummer
2000000
1000000
0
Discharge(GPD)
PC W Efficiency_1PC E Efficiency_1CC Efficiency_1
FallSummerFallSummerFallSummer
1.0
0.5
0.0
TPRemoval(Percent)
PC W Magnitude_1PC E Magnitude_1CC Magnitude_1
FallSummerFallSummerFallSummer
1.6
0.8
0.0
TPRemoval(Mean)

16. Dissolved Reactive Phosphorus Summary

17. Dissolved Reactive Phosphorus
FallSummer
PC WestPC EastPC InflowCC OutflowCC InflowPC WestPC EastPC InflowCC OutflowCC Inflow
3.0
1.5
0.0
DRP(mg/L)
PC West Discharge GPDPC East Discharge GPDColdwater Discharge GPD
FallSummerFallSummerFallSummer
2000000
1000000
0
Discharge(GPD)
PC W Efficiency_2PC E Efficiency_2CC Efficiency_2
FallSummerFallSummerFallSummer
1
0
-1
DRPRemoval(Percent)
PC W Magnitude_2PC E Magnitude_2CC Magnitude_2
FallSummerFallSummerFallSummer
0.8
0.4
0.0
DRPRemoval(Mean)

18. Combined Daily Load Reduction Summary

19. Moving Forward
• Substantial concentration and load
reductions due to the wetlands -
good percentage of stream flows
treated
• Discharge levels are often at or
below recommended nutrient levels
- when discharge does exceed
recommended levels, there are still
substantial load implications to
recognize
• Existing wetlands can be expanded
into the lake with the littoral
wetland expansions – this will
greatly increase retention time of
water and expand capacity – dialing
up the total stream flow captured
• Our wetlands work – despite their
small size - we need more of them

20. Overarching Conclusions
• Need to continue watershed efforts!
– Winter manure ban, nutrient management plans,
soil testing, local collaborative groups such as Ag
Solutions, research and pilot new manure
technologies, research more edge of field
practices or nutrient reduction strategies
(retention ponds, saturated buffers, tile
bioreactors, blind inlets, etc.), investigate new
sites for additional wetlands, and outreach
• Results provide potential future template for
management strategies

21. Thank You
Wright State University
Lake Campus
A SPECIAL THANK YOU TO SEAN FINKE (ODNR) FOR DAY TO DAY
MAINTENANCE AND OPERATIONS OF THE TREATMENT TRAINS, GREG
MCGLINCH (WSU-LC) FOR ASSISTANCE HELPING TO SET UP MONITORING
GAUGES, AND LAKE RESTORATION COMMISSION AND LAKE IMPROVEMENT
ASSOCIATION FOR SUPPORTING AND HELPING TO FUND THE
CONSTRUCTION, MAINTENANCE, AND MONITORING OF GLSM TREATMENT
TRAINS