Post on 23-May-2020
Inês Ribeiro
ines.ribeiro@mottmac.com
A case study: Ogston Reservoir
The role of ecosystem services in decision making
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Water quality – Defining the problem
- Exceedances in Ogston Reservoir prompt
investigation of source
- Plant Protection Products (PPPs)
- Nutrients
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Decision on whether to value or not (WAT-AST)
Monetisation of benefits –
(Stage 1 valuation) Cost to STWL
(Corporate Optimiser)
UKWIR framework
Potential impacts of
intervention scenarios
(WAT-AST)
BCR
(Including Sensitivity Analysis)
Methodology Recommended interventions
Qualitative assessment Quantitative assessment
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SWAT model results
Metaldehyde
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Cost Benefit Analysis Scenarios
Scenario Description
1.1
Metaldehyde substitution1.2
1.3
MCPA and 2;4D substitution1.4
2.1PPP management
2.2Nutrient management
2.3PPP & nutrient management
3.1Abstraction management
4.1 Metaldehyde removal at WTW
4.2MCPA and 2;4D removal at WTW
MCPA and 2;4D
Metaldehyde
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Collaborative approach
OgstonReservoir
STWL experience
Catchment advisor
Site visit
Literature review
EA
Farmers
08/03/2017 Mott MacDonald | NEP Catchment Management Investigations 9
Substitution Advice Treatment
Ecosystem Service(s) 1.1 1.2 1.3 1.4 2.1 2.2 2.3 4.1 4.2
Fresh water ˄ ˄ o o ˄ ˄ ˄ ˄ ˄
Water for non-consumptive use o o o o ˄ ˄ ˄ o o
Air Quality regulation o o o o ˄ ˄ ˄ ˅ ˅
Climate regulation o o o o o o o ˅ ˅
Pest regulation, Erosion regulation, Water regulation,
Provision of habitat, Photosynthesis o o o o ˄ ˄ ˄ o o
Pollination ˄ ˄ ˅ ˅ ˄ ˄ ˄ o o
Water purification and waste management, Recreation
and tourism o o o o ˄ ˄ ˄˄ o o
Aesthetic value ˄ ˄ o o ˄ ˄ ˄ o o
Intellectual and scientific, educational o o o o ˄ ˄ ˄ ˄ o
Social relations ˄ ˄ ˄ ˄ ˄ ˄ ˄ ˅ ˅
Nutrient cycling ˅ ˅ ˅ ˅ ˄ ˄ ˄ ˅ ˅
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Cost Benefit Analysis Scenarios
Scenario Description
1.1 Metaldehyde substitution in high risk areas of the Ogston Reservoir catchment (51% of arable land or
2.83km2)
1.2 Metaldehyde substitution in high and medium risk areas of the Ogston Reservoir catchment (89% of
arable land or 4.91km2)
1.3 MCPA and 2;4D substitution on all improved pasture in Ogston Reservoir catchment (improved pasture
covers an area of 15.12 km2 or 54% of the catchment)
1.4 MCPA and 2;4D substitution on high risk areas in Ogston Reservoir catchment (7.93 km2, 52% of
improved pasture)
2.1 PPP management in Ogston Reservoir catchment: catchment advisor to run information events, hold
one-to-one meetings with farmers, advise on good practice
2.2 Nutrient management in Ogston Reservoir catchment: catchment advisor to run information events,
hold one-to-one meetings with farmers, advise on good practice
2.3 PPP & nutrient management in Ogston Reservoir catchment: catchment advisor to run information
events, hold one-to-one meetings with farmers, advise on good practice
3.1 Abstraction management: No abstraction at Ambergate during November and December
4.1 Metaldehyde removal by advanced oxidation at Ogston WTW
4.2 MCPA and 2;4D removal by existing processes (GAC Filtration) at Ogston WTW with regeneration
frequency aligned to PPP peak concentrations
NOT ASSESSED
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Corporate Optimiser
Assessing CAPEX and OPEX of interventions
Substitution
• Farm infrastructures
• Advice
• Subsidies
• Staff
Advice
• Grants (infrastructure)
• Advice
• Staff
Treatment
• GAC (OPEX)
• AOP (CAPEX+OPEX)
Monitoring
Mott MacDonald | NEP Catchment Management Investigations 12
Scenario Ecosystem service benefits Risk of
failure
Annual
avoided
costs
Counterfactual None 100% £0
1.1 12.7km length of river, 0.79km² area of waterbodies 20% £44000
1.2 12.7km length of river, 0.79km² area of waterbodies 15% £44000
1.3 None 15% £112000
1.4 None 20%£112000
2.1 12.7km length of river, 0.79km² area of waterbodies 90% £22000
2.2 12.7km length of river, 0.79km² area of waterbodies 90% £22000
2.3 12.7km length of river, 0.79km² area of waterbodies 80% £22000
4.1 None 5% £44000
4.2 None 10% £44000
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BCR value
range
Interpretation
<0.5 Measures are unlikely to be worthwhile in economic terms
Between 0.5-
1.5
Additional benefits could be worthwhile in economic terms. The stability of the BCR
value can be tested through sensitivity analysis or the intervention could be explored
further using the EA WAT Stage 1+ or Stage 2 Valuation tools if results are not clear
or a contentious issue requires more granular assessment.
> 1.0 Represents value for money and measures are worthwhile in economic terms if the
BCR is stable following sensitivity analysis.
> 1.5 Represents value for money and measures can be considered worthwhile in
economic terms with greater degree of certainty.
EA Stage 1 Valuation Tool
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Intervention scenarios BCR Additional Benefits (not monetised)
1.1 – Substitution metaldehyde: high
risk areas>1.0 Aesthetic values and social relations
1.2 – Substitution metaldehyde: medium
and high risk areas>1.0 Aesthetic values and social relations
1.3 – Substitution MCPA and 2;4D: all
improved pasture
0.5-1.0 Social relations
1.4 – Substitution MCPA and 2;4D: high
risk areas
0.5-1.0 Social relations
2.1 – Farming advice: nutrients 0.5-1.0 Pest management, erosion management, aesthetic
values, intellectual and educational values and social
relations
2.2 – Farming advice: PPPs 0.5-1.0 Pest management, erosion management, aesthetic
values, intellectual and educational values and social
relations
2.3 - Farming advice: Nutrients and
PPPs>1.0 Pest management, erosion management, aesthetic
values, intellectual and educational values and social
relations
4.1 – Treatment: AOP <0.5 Intellectual and educational values
4.2 – Treatment: GAC filtration <0.5 None
Costs and Benefits Illustration (assuming WFD status improvements)
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Intervention scenarios BCR (WFD status
improved)
BCR (No WFD
improvements)Reasoning
0 – Counterfactual scenario 0.00 0.00 BCR of 0 with significant costs associated
1.1 – Substitution metaldehyde:
high risk areas>1.0 0.5-1.0 Second highest BCR due to avoided outage and fine costs, and
valued benefits to mammals, birds and pollinators.
1.2 – Substitution metaldehyde:
medium and high risk areas>1.0 0.5-1.0 Highest BCR due to avoided outage and fine costs, and valued
benefits to mammals, birds and pollinating insects. Highest BCR
because lower failure risk as effective over a larger area.
1.3 – Substitution MCPA and
2;4D: all improved pasture0.5-1.0 0.5-1.0 BCR is lower than scenarios 1.1 and 1.2 because there are no
additional valued benefits to mammals, birds and pollinating insects.
1.4 – Substitution MCPA and
2;4D: high risk areas0.5-1.0 0.5-1.0 Lower than 1.1 and 1.2 because no additional valued benefits to
mammals, birds and pollinating insects
2.1 – Farming advice: nutrients 0.5-1.0 <0.5 Is not recommended and does not pass sensitivity tests despite
benefits to all six NWEBS components. Has a very high risk of failure
(90%)
2.2 – Farming advice: PPPs 0.5-1.0 <0.5 Is not recommended and does not pass sensitivity tests despite
benefits to all six NWEBS components. Has a very high risk of failure
(90%)
2.3 - Farming advice: Nutrients
and PPPs>1.0 <0.5 Third highest BCR which passes sensitivity testing for rivers
assuming improvements to WFD status. Despite high risk of failure
(80%), significant and multiple benefits have been identified in the
AST.
4.1 – Treatment: AOP <0.5 <0.5 Combined BCR <0.5 and costs of investment outweigh cost
savings from outages and fines
4.2 – Treatment: GAC filtration <0.5 <0.5 BCR below 0.5 and it does not survive sensitivity tests with no
additional benefits identified in the AST.
Benefit cost ratio (BCR)Ogston catchment management intervention scenarios
𝐵𝐶𝑅 =𝑃𝑉 𝐵𝑒𝑛𝑒𝑓𝑖𝑡𝑠 (£)
𝑃𝑉 𝐶𝑜𝑠𝑡𝑠(£)
Pollution Swap
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Recommendations
1To reduce
metaldehydeconcentrations to below
PCV
Metaldehyde substitution with
ferric phosphate on high and
medium risk areas of arable
land.
2To reduce MCPA and
2;4D concentrations
to below PCV
Removal by existing
processes (GAC filtration) with
regeneration frequency aligned
to PPP peak concentrations +
farm advice.
3To reduce nutrients concentration in the
Ogston Reservoir
Farming advice relating to
PPP & nutrient management
in Ogston Reservoir catchment.
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Qualitative and
quantitative
assessment
A case for ecosystem services
• The methodology accounts for investments into the environment
• Diffuse pollution management at a catchment scale
• Investment targets effective catchment management interventions
• Collaborative approach