Transcript Generic CatchIS Presentation

Pesticide Model – Full Details
Top Pesticides
Runs for Surface Water Catchments and for Ground Water boreholes:
Data export option
to Excel:
SWAT Model - Top Pesticides
Catchment based threshold exceedence
Uses either Seasonal exposure or Pesticide specific loadings :
SWATCATCH Model
Catchment based threshold
exceedence
Groundwater assessment for all
boreholes
Groundwater assessment for a
single borehole
Identify Catchment Hot-Spots:
Ground Water:
GWAT Model
Soil, pesticide, climate data
g/w resources identified from EA g/w
vulnerability mapping and SPZs
Soil leaching
model
(MACRO)
Attenuation
factor model
(unsat zone)
‘local’ g/w
Using id for
likely g/w
resources
aquifers
Using id EA
major/minor
aquifers
boreholes
Grids in
SPZ
Identify Catchment Hot-Spots
Surface Water:
SWAT Model - Catchment Hot-spots
Bespoke Reporting Output
Current Developments
Nitrates, Climate Change, Leakage and AMP
Current Developments - Nitrates
Surface water Nitrate model
Calculates the agriculturallyderived nitrate concentrations at
the surface water abstraction
point based on the amount of
leachable N available for
transport over the whole sub
catchment area that feeds the
surface water source
Integrates land use, soil and
climate zone data over the sub
catchment
Current Developments - Nitrates
Surface water Nitrate model - Output
Yearly Spread - Nitrate for Upper Severn
Mean flows (ml/day)
Base flows (ml/day)
Nitrate NO3 conc (mg/l)
30000
35
25
Flow (ml/day)
20000
20
15000
15
10000
10
5000
5
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Year
Nitrate NO3 Concentration (mg/l)
30
25000
Current Developments - Nitrates
Groundwater Nitrate model
V = volume
N = Nitrate
Store starts with no nitrate or volume
Instant input from model
N1V1
STEP 1
GW Store N1V1 in store
at step end
Becomes
Step 2 start
V and N
N0V0
Output to baseflow
Instant input from model
N2V2
STEP 2
GW Store
N2V2 in store
N1V1
Output to baseflow
at step end
Becomes
Step 3 start
V and N
Instant input from model
N3V3
STEP 3
GW Store
N3V3 in store
at step end
N2V2
Output to baseflow
Current Developments - Nitrates
Groundwater Nitrate model - Output
Yearly Spread - Nitrate for 1km around AMEN CORNER
Weather Data = Current
storage (m³/week)
vol to gwater store (m³/week)
Nitrate N conc in recharge(mg/l)
Nitrate N conc in gwater store (mg/l)
500000
25
450000
400000
20
300000
15
250000
200000
10
150000
100000
5
50000
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Year
Concentration (mg/l)
Flow (m³/week)
350000
Current Developments – Climate Change
Current
Data
Derivation of Scenario Weather Data
UKCIP02 climate change scenario data
Monthly precipitation and temperature for 30 year timeslice (e.g.
2020’s =2011-2030)
Calculation of simple water balance model
Precipitation – potential evapotranspiration balance to derive
monthly HER. Problems with PET calculation from temperature
Derivation of weekly HER
Distributed corresponding to current patterns within each month
Scenario HER
Weather time-series for each10 weather stations snapped into
CatchIS module
Impact on Pesticide Risk
Maun to Alders sub-catchment
Isoproturon on wheat
Yearly Spread - Isoproturon on Wheat for Maun to Conjure Alders
Weather Data = Current
Mean flows (m³/S)
Base flows (m³/S)
Mean Pesticide conc (ng/l)
Yearly Spread - Isoproturon on Wheat for Maun to Conjure Alders
Weather Data = 2020 - Low Distributed
Peak Pesticide conc (ng/l)
6
Mean flows (m³/S)
160
Base flows (m³/S)
Mean Pesticide conc (ng/l)
Peak Pesticide conc (ng/l)
6
160
140
140
5
5
60
2
100
3
80
60
2
40
1
40
1
20
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Year
CURRENT
20
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Year
2020 LO
• Lower mean flows
• Smoothing extreme events
• Likelihood of threshold exceedence slightly increased
Concentration (ng/l)
80
4
Flow (m³/S)
Flow (m³/S)
100
3
120
Concentration (ng/l)
120
4
Current Developments –
Leakage and Asset Management
Pipe failure (Corrosivity, Sharps, Sand and Heave)
Leakage and Asset Management
Leakage management is an important element in the supplydemand balance and AMP for water supply companies.
Progressively leakage has become a political issue and
OFWAT has imposed annual mandatory targets for all water
companies.
Leakage reduction is important in the management of water
supplies and its contribution to the sustainable management of
water resources.
CIWEM’s position
CIWEM recognises the considerable reductions in leakage made by
water companies in recent years.
CIWEM recommends that a Best Available Technique not Entailing
Excessive Cost (BATNEEC) type approach be considered for leakage
target setting within an economic framework.
CIWEM recommends that the ownership of supply pipes be transferred
to the water companies.
CIWEM recommends that in the long term, all water use should be
metered for the purposes of water conservation and more accurate
leakage measurement.
CIWEM supports an holistic approach to leakage control, by
considering the components of leakage and selection of appropriate
policies.
Causes of leakage
Failure in the water mains network
How?
Age of pipe
Diameter of pipe
Source of feed
‘Bus’ loading
Soil Heave potential
Soil Corrosivity potential
How soils affect leakage
Lower corrosivity
Less heave
Higher corrosivity
More heave
How soils affect leakage
Potential areas of development
 Erosion risk
 Cryptosporidia risk