ISRIC Green Water Team
Sjef Kauffman
Godert van Lynden
Zhanguo Bai
1
Water and Sustainable Land Management
•
•
Instead of a narrow focus
on surface and ground
(“blue”) water alone,
more attention is needed
for the green water
component: water in the
soil available for plant
growth;
The green water
component comprises at
an average 2/3 of total
rainfall (Falckenmark and
Rockstrom, 2006);
Starting points
•
•
•
•
•
Key resource is rain water
Farmer can improve local
water balance
Upstream land management
is linked to downstream
water availability
Farmers are key and need
support to make
investments
How can we support the
farmers?
3
More water cannot be created, but:
Current land management practices
show wasting of rain water by :
• high rates of surface runoff
enhancing flash floods and erosion,
and
• large losses by evaporation of water
directly from bare soil (up to 60% of
rainfall!)
Blue water can be better managed
by good soil & water management:
•
•
•
•
reducing runoff and erosion,
more infiltration,
less unproductive evaporation,
more water for plant growth
Better soil and water management
can also greatly increase water supply
downstream and improve rural livelihoods
5
Farmers know the benefits from green water management, but
need incentives to cover the costs/ labour
Green Water Credits bridge the incentive gap:
Compensation by water users to water providers for
specified water management services
6
Targets/Potential benefits
7
Who and where are the key players?
8
4 Work Domains
1. Biophysical analysis
2. Socio-economic study
3. Institutional inventory
4. Financial Mechanism
Estimated increase in hydro-power from green water
management (50% cut in erosion/siltation)
Hydropower Generation
Scenario: upland_management, All months
g
b
c
d
e
f
b
c
d
e
f
g
b
c
d
e
f
g
b
c
d
e
f
g
b
c
d
e
f
g
200
180
160
Masinga
Kindaruma
Kiambere
Kamburu
Gitaru
140
120
100 000 GJ =
100
51 000 barrels oil
80
= $ 5.8 million
60
40
20
0
1989 1992 1995 1998 2001 2004 2007 2010 2013 2016 2019 2022 2025 2028
10
Green Water Credits
(Algeria, China?,
Ethiopia??, Burundi??)
(Morocco)
(Kenya)
Phase I
Proof-of-Concept/
Business Case
Phase II
Design and capacity
building
Phase III
Implementation
11
Results
Started 2006
Currently implemented in
• Kenya, Upper Tana Basin
(Phase II, till Sept. 2011:
Project Design)
• Morocco: Sebou Basin (Phase
I, till Sept. 2011: Proof of
Concept)
• Algeria (Project preparation)
• China, (Proposal)
12
Upper Tana, Kenya
Sebou Basin, Morocco
CHN43 Pits
Quest
CHN45 Terrace
Id
SWC Technology Name
CHN47 Check Dam
160 measurements
trees
Measurements/
160 measurements
crop
LGP Estimates
PlantType
3.08
Soil
Produc Prod Loss
2.7
108% 58
tion
Diff% (t/ha)
180 estimates
3.5
10.34
Soil
SoilLoss
122
68%
LossDiff Diff%
2
Runoff
(% of
4
rainfall)
Runoff Runof
6
60%
Diff
Diff%
110
70
39%
30
18
38%
WOCAT in GWC
77%
8
80%
CHN49 Caragana Korshinskii Planting----a kind 160 estimates
of SWC vegetative technology
ETH01 Trashlines
90 estimates
Stipa
3.375
bungeana
mixed cereals 1.3
& pulses,
cotton
75
95
56%
2
8
80%
10
90
90%
25
45
64%
ETH04 Hillside Terracing
90
measurements
30
ETH11 Multiple Cropping
90
estimates
grass/bush/tr 13
ee
Sorghum
0.9
50%
10
40
80%
KEN05 Fanya Juu Terrace
90
estimates
maize
1.5
50%
2
9
82%
20
30
60%
KEN10 Road runoff management - Nyeri
120 estimates
1.35
25%
15
10
40%
20
30
60%
KEN11 Road runoff system - Mwingi
105 estimates
all
1.5
2
10
83%
10
70
88%
KEN15 double dug beds - Busia experience
120 measurements
maize
2
150%
5
10
67%
40
KEN16 Grevillea tree planting as an
100
agroforestry intervention
KEN22 Water Harvesting and Enlarged
90
Structures
KEN22 Water Harvesting and Enlarged
90
Structures
KEN22 Water Harvesting and Enlarged
90
Structures
KEN22 Water Harvesting and Enlarged
90
Structures
KEN23 Riverbed reclamation & silt trapping for 75
sugarcane
KEN24 Gully Reclamation
60
estimates
coffee
7.5
0%
3.5
1.5
30%
35
5
13%
estimates
maize
1.2
100% 0.8
7.2
90%
7
38
84%
estimates
beans
0.6
0.8
7
estimates
sugarcane
5
0.8
7
estimates
banana
3
0.8
7.2
90%
7
38
84%
estimates
sugarcane
5
5
7
58%
20
40
67%
estimates
banana
4
0.6
609.4
100%
10
50
83%
KEN24 Gully Reclamation
60
estimates
pawpaw
8
0.6
10
KEN24 Gully Reclamation
60
estimates
grass
0.6
10
KEN25 Pasture Mangt. through Removal of
comiphora
KEN26 Water Table Management
70
estimates
comiphora
1
70
estimates
sugarcane
KEN27 Gully blocking by stone checks
120 estimates
fruit trees
KEN30 Conservation Tillage through ripping
120 estimates
wheat
6
2.7
2
67%
8
12
60%
100% 0.5
1
67%
4
4
50%
0.5
5
91%
10
40
80%
20
30
60%
80%
0
Examples from WOCAT database
(> 350 technologies worldwide)
CONCLUSIONS
• GWC is a financial facility to support farmers in soil
and water conservation activities:
1. For initial investments (short term)
2. For maintenance investments (long term) in
appropriate green water management
3. Where downstream water users compensate
farmers upstream for the benefits derived from
appropriate soil and water management
22
More information...
www.isric.org
www.greenwatercredits.net
www.wocat.net
Godert.vanlynden@wur.nl
Sjef.Kauffman@wur.nl
Zhanguo.Bai@wur.nl