Agricultural Nutrient and Surface Water- Groundwater InteractionsSarah Rixon, Elisha Persaud, Jana Levison, Andrew Binns | School of Engineering, University of Guelph

ResultsContinuous Sampling in Groundwater and Surface Water

IntroductionThere are few studies that feature simultaneous analysis of groundwater and surface water quality and processes in agriculturally dominant watersheds.

The understanding of nutrient transport through surface water and groundwater interactions is important for the sustainability of acceptable water quality for human and ecological health especially within the Great Lakes Basin.

ObjectivesØ Examine spatial and temporal dynamics of nitrate and phosphorus

in surface water and groundwater Ø Relate the dynamics to hydrologic and geologic characteristics,

land use and meteorological conditions within the sub-watershedØ Develop a conceptual model to illustrate the processes and

variations of nutrient transport and surface water and groundwater relationships

Study LocationØ The Upper Parkhill Watershed is approximately 150 km2

Ø It is a clay based agriculturally dominant areaØ The main research site is located near Parkhill, Ontario within the

jurisdiction of the Ausable Bayfield Conservation AuthorityØ It is at an Integrated Water and Climate Monitoring Station

developed by the Ministry of Environment and Climate Change (MOECC) for a Great Lakes Basin monitoring project

Sampling Methods

Discrete Sampling in Groundwater and Surface Water

SummaryØ Nitrate values regularly exceed the Canadian

Drinking Water Standard of 10 mg/L and the Canadian Environmental Quality Guidelines for aquatic life of 13 mg/L of nitrate-N in surface water

Next Steps Ø Continue discrete monthly sampling and

continuous sampling for one yearØ Install lysimeters in agricultural fields as well as

conservation authority land Ø Survey land owners about agricultural practices

and pesticide use and application

Ø Concentrations in the groundwater range from 0 to 0.3 mg/L nitrate-N and 0.1 to 25 mg/L nitrate-N in surface water

Ø Concentrations of soluble reactive phosphorus range from 0 to 0.069 mg/L in groundwater and 0 to 0.099 mg/L in surface water

Ø Concentrations of total dissolved phosphorus are below the detection limited of 0.07 mg/L in groundwater and range from 0 to 0.079 mg/L in surface water

Ø Concentrations of plant available phosphorus range from 2.55 to 38.0 mg/L in dried streambed sediment

# Name Purpose

1Satlink Telemetry System

Two setups are installed to power equipment and log data from EXO and SUNA every 15 minutes for surface water and groundwater

2 Sensor Enclosure

Enclosure for SUNA and EXO for protection in stream

3 Satlantic SUNATM V2

In-situ nitrate sensor and sensor set up for long term deployment in well

4YSI EXOTM

Water Quality Sonde

Measures EC, DO, pH, temperature, turbidity and water depth and sensor set up for long term deployment in well

5

Discrete Sampling Set Up

Monthly collection of groundwater and surface water samples for ion chromatography analysis and lab analysis for soluble reactive phosphorus, total dissolved phosphorus

6 Lysimeter

Three lysimeters are installed on conservation land and used to collect root zone water samples for ion chromatography analysis of nitrate

Acknowledgments

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Ø High concentrations of nitrate and phosphate can influence the growth of algae blooms in Parkhill Creek which is a tributary to Lake Huron

Ø The pH in surface water ranges from 7.5-8.8 and 6.5-8.5 in groundwater at the main site

Ø Davin Heinbuck and Alec Scott from the Ausable Bayfield Conservation Authority

Ø Scott MacRitchie from the MOECCØ Haley Wallace and Clare Robinson from The University

of WesternØ Rebecca Beutel, Scott Gardner, Graeme MacDonald,

David Browne from the University of Guelph

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Continuous Nitrate and Electrical Conductivity from July 17, 2017 to July 21, 2017 Continuous Nitrate and Electrical Conductivity from October 5, 2017 to October 9, 2017

Monthly Nitrate Concentrations in Surface Water Locations

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Ø Shallow Wello 6.7 meters deepo 2 year old watero 2.28 ± 0.31 Bq/L of radon

Ø Deep Wello 15.85 meters deepo 4 year old watero 1.07 ± 0.12 Bq/L of radon

Ø Stream at Siteo 0.14 ± 0.03 Bq/L of radon

Ø Stream at MCGo 2.59 ± 0.03 Bq/L of radon

Ø Stream at MCARo 0.43 ± 0.08 Bq/L of radon

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(YSI,2013)