Transcript Slide 1

The potential benefits of
Green Water Credits
Part 2:
Quantifying profits for
downstream water users
Peter Droogers
Wilco Terink
Johannes Hunink
Sjef Kauffman
Godert van Lynden
WHAT to quantify?
• Supply  Biophysicial
assessment
• Supply vs. Demand 
Cost-benefit analysis
OVERALL BENEFIT-COST ANALYSIS
Recall: changes in supply
Required: an integrating tool
• Impact of changes in water-soil dynamics on:
– upstream
• rainfed improved production
– downstream
• hydropower
• domestic water supply
• irrigation
• Benefit-cost analysis
• Integrations tool: WEAP
WEAP Tool
WEAP: Validation
Masinga Inflow
Masinga Outflow
Kamburu Outflow
Gitaru Inflow
Kindaruma Outflow
Kiambere Outflow
Changes reservoir storage
Reservoir Storage Volume
All Reservoirs (9), All months (12)
00_Base
01_Bench
02_ConsTill
03_ContTill
04_FanyaJuu
05_GrassStrips
06_MicroCatchments
07_Mulching
08_Rangelands
09_Ridging
10_Riverine
11_TrashLines
60
55
50
Million Cubic Meter
45
40
35
30
25
20
15
10
5
0
Jan
2005
Mar
2005
May
2005
Jul
2005
Sep
2005
Nov
2005
Jan
2006
Mar
2006
May
2006
Jul
2006
Sep
2006
Nov
2006
Results: Reduction in water shortage
Unmet Demand
All Demand Sites (13), All months (12)
00_Base
01_Bench
02_ConsTill
03_ContTill
04_FanyaJuu
05_GrassStrips
06_MicroCatchments
07_Mulching
08_Rangelands
09_Ridging
10_Riverine
11_TrashLines
0.0
-0.5
-1.0
Million Cubic Meter
-1.5
-2.0
-2.5
-3.0
-3.5
-4.0
-4.5
-5.0
-5.5
-6.0
-6.5
-7.0
2005
Results: Increase in hydropower
Hydropow er Generation
All Reservoirs (9), All months (12)
00_Base
01_Bench
02_ConsTill
03_ContTill
04_FanyaJuu
05_GrassStrips
06_MicroCatchments
07_Mulching
08_Rangelands
09_Ridging
10_Riverine
11_TrashLines
180
Thousand Gigajoule
160
140
120
100
80
60
40
20
0
2005
Results: Increase in Benefits
Results: Benefit-Cost Analysis
Benefits
Benefits
01_Bench
01_Bench
02_ConsTill
02_ConsTill
03_ContTill
03_ContTill
04_FanyaJuu
04_FanyaJuu
05_GrassStrips
05_GrassStrips
06_MicroCatch
06_MicroCatch
07_Mulching
07_Mulching
08_Rangelands
08_Rangelands
09_Ridging
09_Ridging
10_Riverine
10_Riverine
11_TrashLines
11_TrashLines
mUS$/y
mUS$/y
9.9
9.9
1.0
1.0
4.9
4.9
9.0
9.0
5.3
5.3
1.6
1.6
5.1
5.1
0.8
0.8
8.9
8.9
2.0
2.0
3.4
3.4
Costs
Costs
ha
ha
92,865
92,865
52,766
52,766
52,766
52,766
92,865
92,865
92,865
92,865
1,000
1,000
92,865
92,865
136,916
136,916
52,766
52,766
10,000
10,000
92,865
92,865
B/C
B/C
Construction
Construction Maintenance
Maintenance
US$/ha
US$/ha
US$/ha
US$/ha/y
/y
mUS$/y
mUS$/y
100
100
20
20
2.8
2.8
00
00
0.0
0.0
00
00
0.0
0.0
200
200
20
20
3.7
3.7
50
50
20
20
2.3
2.3
500
500
20
20
0.1
0.1
00
00
0.0
0.0
50
50
00
0.7
0.7
100
100
20
20
1.6
1.6
100
100
20
20
0.3
0.3
50
50
20
20
2.3
2.3
• 20% of area ~ 100,000 smallholders
mUS$
mUS$
7.1
7.1
1.0
1.0
4.9
4.9
5.3
5.3
3.0
3.0
1.5
1.5
5.1
5.1
0.1
0.1
7.3
7.3
1.7
1.7
1.1
1.1
DISCUSSIONS, CONCLUSIONS
Wrapping up
• GWC beneficial for:
– upstream
– downstream
• Analysis tools:
– SWAT: (upstream) supply
– WEAP: (downstream) demand
• Steps
– Understand current situation
– Explore options
• GWC
–
–
–
–
Biophysical component
Socio-economics
Institutional
Financial
Discussion / conclusions
• Smaller focus area
– Current study: 1.8 million ha total; 0.5 million ha rainfed
– Target areas
– C/B analysis
• Definition of GWC options
– Practical WOCAT expertise in implementation phase
• Monitoring network
– Update according to recently finished survey
– Indicators to evaluate effectiveness of implementation
THANK YOU