Remediation of Agricultural Diffuse Water Pollution by Farm Ponds and Wetlands

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15th of March 2006
Remediation of Agricultural Diffuse Water
Pollution by Farm Ponds and Wetlands
Fabrice Gouriveau PhD, School of GeoSciences
Supervisors Dr. Kate Heal Dr. Graham Russell
(School of GeoSciences) Dr. Andrew Vinten
(Macaulay Institute)
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CONTENTS

• Background
• Objectives of the Study
• Study Sites
• Materials Methods
• Anticipated Research Outcomes

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BackgroundAgriculture and diffuse water pollution

• Agricultural water pollution NO3-, P,
  pesticides, faecal pathogens from arable fields,
  grasslands, farmyards, etc.
• Diffuse pollution spread over catchment,
  significant collective impact difficult to
  identify and contain
• Degradation of water quality aquatic
  ecosystems siltation, toxicity to organisms and
  eutrophication
• High costs loss of profit for fisheries, paper
  mills, tourism water filtration/treatment loss
  of biodiversity enjoyment

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BackgroundMitigation of agricultural diffuse
water pollution
Among other Best Management Practices
Ponds and Wetlands are recommended to catch
contaminated farm runoff and improve its quality !
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BackgroundMitigation of agricultural diffuse
water pollution

• Ponds and wetlands improve water quality by
• Uptake, inactivation of pollutants by
  microorganisms plants
• Adsorption on the surfaces of plants, sediments,
  litter
• Settling of suspended solids
• Die-off of pathogens

Good treatment efficiency but variable temporally
and spatially !
Negative impacts ecosystems, safety, health,
GHGs, pollution
Many questions long-term performance, optimal
design, carrying capacity, impact on
biodiversity, etc.
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Objectives of the Study

1. Assess the water treatment performance of farm
   ponds/wetlands
2. Assess the ecology of farm ponds/wetlands
3. Assess the socio-economic aspects of farm
   ponds/wetlands
4. Develop a model for farm ponds/wetlands

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Study Area
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Study Sites
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Materials Methods

• 1) To assess water treatment performance of farm
  ponds
• Monitor water quality at inlet, outlet (samplers,
  probe)
• Describe hydraulic balance (flow meters, tracers)
  
• Assess sedimentation rate sediment quality
  (cores)
• Manipulate water level hydraulic residence time

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Materials Methods

• 2) To assess the ecology of farm ponds
• Vegetation surveys (quadrats)
• Macroinvertebrate surveys (kick sampling)

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Materials Methods

• 3) To assess socio-economic aspects of farm
  ponds
• Collect data on construction/maintenance costs
  and benefits (questionnaires, databases)
• Assess farmers "acceptance" of treatment ponds
• 4) To develop a model of ponds/wetlands
• Adapt, calibrate and run an existing model

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Anticipated Research Outcomes

• Information on how ponds perform water treatment
  and on the factors influencing their performance
• Information on the impacts of the ponds on
  biodiversity
• Evaluation of the cost-effectiveness of
  ponds/wetlands
• Recommendations for optimum pond design and
  management
• Modelling of the pond system
• Communication and technical tools for farmers,
  SEPA

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Thanks for your attention !
Questions and Suggestions are very welcome !