What will be the impact of water scarcity on food security?
Post on 19-May-2015
3767 Views
Preview:
DESCRIPTION
Transcript
What will be the impact of water scarcity on food security?
COLIN CHARTRES
International Water Management Institute
CONTENTS
• A history lesson• Reasons for increasing water scarcity• Adaptive responses• Policy responses• A call to action
Water for Food – 1 liter per calorie
Liters of Water
Daily Drinking Water 2 – 5 Liters of Water
Daily Household Use 20 – 500 Liters of Water
1kg of Grain 500 to 2,000 Liters of Evapotranspiration (ET)
Livestock products (meat, milk)
5,000 to 15,000 Liters of ET
2.5b more mouths means finding another 2500 - 5000 cubic km of water!
A Middle Eastern History Lesson (with acknowledgements to Coucier et al., 2005)
1950 Mid 1970s
LJRB (cont.)
2000s Mid 2020s
LJRV - history
In 60 years:• 10,000 – 46,000 ha of irrigation• All surface water committed• Groundwater being severely mined• Flows into Dead Sea reduced by c.80%The question is have the development benefits
outweighed the environmental costs?There has been some very dubious use of water
for poorly returning agriculture.
An Indian History Lesson
The Indian Groundwater Story
Transformation of Indian irrigation net area (million ha) by irrigation source (after Shah, 2009)
1800 1850 1885-86 1938-39 1970-711999- 2000
Government canals <1 ~1 2.8 9.8 24.2 31.2
Wells 2.0 2.6 3.5 5.3 13.9 53.6
Other sources 4.0 4.4 3.0 6.4 6.8 6.7
All sources 6 7 9.3 21.5 44.9 91.5Irrigation area as % of area sown 10 10.3 12.4 25 31.4 53.5
India’s total available water resources are 1086 km3
Drivers Unit 2000 i
BaUScenario
projections ii
NCIWRDhigh demand
Scenario iiSeckleret al.ii
Rosegrantet al ii
2025 2050 2025 2050 2025 2025Population Million 1,007 1,389 1,583 1,383 1,581 1,273 1,352
- % urban population % 28 37 51 45 61 43 43
Total calorie supply/person/day Kcal 2,495 2,775 3,000 - - 2,812 -
Total grain demand/person/year Kg 200 210 238 231 312 215 215
Gross irrigated area Mha 76 105 117 98 146 90 76
Total grain availability/person/year Kg 208 213 240 242 312 216 206
Net irrigation requirement Km3 245 313 346 359iv 536iv 323 332
Domestic water demand/person m3/day 33 45 64 45 70 31 31
Industrial water demand/person m3/day 42 66 102 48 51 55
Total water demand Km3 680 833 900 773 1,069 811 822
A Pending Crisis for India
• India is rapidly running low on water resources• Seckler et al. (1999) warned that a quarter of India’s food
harvest is at risk if the country fails to manage it groundwater resources properly.
• The transformation of its irrigation system from surface to groundwater has confounded good planning
• Shah describes the current groundwater irrigation set up as “atomistic” and anarchic
• Government control and regulation is extremely limited• Many aquifers are already over exploited• A National River Linking Program has been proposed,
but will be expensive and environmentally contentious
An Australian History Lesson
15% of 15% of AustraliaAustralia
Over 2 million Over 2 million peoplepeople
Ratio of high to low flow in Murray is >15:1 cf 1.9:1 for the Rhine
The Murray-Darling Basin
• The Murray-Darling Basin has a track record of integrated water resources management, but overallocation was not prevented.
• Regional climate variability is a major issue. Connell (2007) suggests that
“……a similar struggle between biophysical realities and human ambition is underway in the Murray Darling Basin where the process of landscape and stream modification has proceeded apace in recent decades largely oblivious of the need for caution or the possibility of threshold changes to its ecological systems.”
Climate variability in the MDB
0
100
200
300
400
500
600
700
800
900
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Extreme floodsExtreme floods
Extreme droughtExtreme drought
Irrigation growth in the Murray-Darling Basin
MDB
• By 1980s there was serious concern about land degradation and river salinity
• Toxic algal blooms in the Darling River in the summer of 1991-92
• 1995: a “cap” on diversions agreed• By turn of the century river rarely flowing into the ocean
and the basin “closed”• The governance mechanism (MDBC) which served well
for about 80 years could not cope with issues because of state based partisan responses and thus the Federal Government took over the basin management (MDBA)
• 2004 onwards; very significant investment in improving irrigation efficiency and buying back water for the environment
What do these lessons tell us?
Open Basins Closed BasinsExploiting water resources Managing Demand
New allocations Reallocating water
Who is included and excluded Safeguarding right to water
Developing groundwater Regulating groundwater
Informal, formal institutions Informal & Formal institutions
Within system conflicts Cross sectoral conflicts
Demand for water is having profound impacts on our river systems and requires new systems of governance that deal with issues arising in closed basins compared with those that operated previously
A WATER CRISIS?
• Food production is dependent on water • There is compelling evidence that water
will be the number one constraint on increasing food production in much of the developing world
• Much of the world is becoming water scarce
WE ALREADY INHABIT A WATER SCARCE WORLD
1/3 of the world’s population live in basins that have to deal with water scarcity
Most hungry and poor people live where water challenges pose a constraint to food production
Hunger Goal Indicator: Prevalence of undernourished in developing countries, percentage 2001/2002 (UNstat, 2005)
>35%
20-35%
However the 2008 food crisis demonstrated that food security depends on a range of factors?
• Income growth and dietary change, climate change, high energy prices, globalization and urbanization are transforming food consumption, production and markets (von Braun (2008)
• Slow growing supply, low stocks and supply shocks at a time of surging demand for feed, food and fuel have lead to drastic price increases
• Biofuel production has further impacted the situation and disproportionately affects the poor through price level and volatility effects
SUB-SAHARAN ECONOMIES ARE STRONGLY DEPENDENTON WATER AVAILABILITY
e.g. Rainfall and GDP growth in Ethiopia
Impact of rainfall variability on GDP and Agricultural GDP growth
-80
-60
-40
-20
0
20
40
60
80
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
year
%
-30-25-20
-15-10-50510
152025
rainfall variabilityGDP growthAg GDP growth
-250
-200
-150
-100
-50
0
50
100
150
200
250
1960 1970 1980 1990 2000
Years
Nat
iona
l rai
nfal
l ind
ex: V
aria
tion
from
tren
d (m
m)
-800
-600
-400
-200
0
200
400
600
800
Tota
l cer
eal p
rodu
ctio
n - V
aria
tion
from
tren
d ('0
00 to
ns)
National rainfall indexCereal production
Burkina Faso: Relation between rainfall and cereal production
A key question is whether we have enough water resources to grow enough food to meet future demand for food, feed and biofuels?
The Comprehensive Assessment answered
No, unless ….We change the way we think and act on
water issues.
KEY QUESTION
Demand continues to rise
We have seen that several basins are already using close to their utilizable water resources yet pressure
for more food and thus water continues to mount
What are the driving forces behind water scarcity?
• Growing population (6.7 billion now to 9.0 billion by 2050)
• Dietary change
• Urbanization
• Biofuel production
• Need for environmental water
• Climate change
0
20
40
60
80
100
120
10 100 1000 10000 100000
GDP per capita (2000 constant dollars per year)
mea
t con
sum
ptio
n (k
g/ca
p/yr
) Meat China
India
0
2 0
4 0
6 0
8 0
1 0 0
1 2 0
1 0 1 0 0 1 0 0 0 1 0 0 0 0 1 0 0 0 0 0
G D P p e r c a p ita (2 0 0 0 c o n s ta n t d o lla r s p e r ye a r )
milk
con
sum
ptio
n
(kg/
cap/
yr)
Milk China
India USA
USA
Consumption and income 1961-2000
BIOFUELS
irrigated
Million ha
Harvested area
irrigated
rain fed
rain fed
biofuels2003
2030
400 800 1200 1600
2000 4000 6000 8000
2003
2030
biofuelsirrigation
irrigation
directly from rain
directly from rain
Crop water consumption
km3
Water requirements for biofuel production, but a word of caution …..
liters of ET Liters of Irrigation water
China 3800 2500
India 4100 3500
US 1750 300
Brazil 2250 200
0100200300400500600700800900
100019
11
1917
1923
1929
1935
1941 1947
1953
1959
1965
1971
1977
1983
1989
1995
2001
2004
Tot
al a
nnua
l inf
low
(GL
)
Annual inflow
1911–1974 (338 GL) 1975–1996 (177 GL) 1997–2004 (115 GL)
Source: WA Water Corporation.
CLIMATE CHANGE: a big uncertainty
INFLOWS INTO PERTH’s STORAGES
Climate Change issues – Ovens Valley, Victoria Australia
For recent climate and current development
• Last 10 years have seen a 11% and 26% reduction in rainfall and runoff.
• Translation of this into a developing country scenario could portend catastrophy
Temperature
Sectoral water consumption is increasing due to increased demand
Demand will double in the next 40 years
A CALL TO ACTION - WHAT CAN WE DO?
Reservoir Storage per Capita (m3/cap), 2003
1,104 1,277
5,961
38687
2,486
3,386
4,717
-
1,000
2,000
3,000
4,000
5,000
6,000
7,000
Ethiopia
South
Africa
Mexico
Tha
iland
China
Brazil
Austra
lia
North Ameri
ca
Water storage improves water and food security
“Irrigation” has dominated public investment in agriculture in Asia.
Very little water storage has been built in Africa.
Irrigated area is only 7% of arable land (3.7% in SSA).
Source: World Bank
RETHINK STORAGE
• Renewed interest in storage infrastructure for irrigation particularly in sub-Saharan Africa
• Explore wide range of options: large scale reservoirs, small village ponds, groundwater, water harvesting (i.e. soil moisture storage), virtual storage (food)
• Diversity of storage options within a basin
• Storage creation processes determine who benefits
• New hydropower schemes and their impacts will be inevitable
REVITALIZE IRRIGATION
Irrigated Area
Food price index
World Bank lending for irrigation
2.5
2.0
1.5
1.0
0.5
01960 1965 1970 1975 1980 1985 1990 1995 2000 2005
320
280
240
200
160
120
80
40
0
Living Planet Index Freshwater Species
How to avoid?
?
Increasing Water Productivity
Figure 4: Standardised Gross Value of Production per unit water consumed by ETcrop
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
US
dolla
r per
m3
* surface water and pub lic wells ** private wells
Water losses
25% 25% conveyance conveyance loss in Riverloss in River
60% on farm 60% on farm loss made up loss made up of:of:
•• 24% water 24% water management management loss (dams, loss (dams, evaporation)evaporation)
•• 36% by plants 36% by plants (14% loss to soil (14% loss to soil and 22% direct and 22% direct plant use)plant use)
15% channel 15% channel distribution distribution lossloss
Gains in productivity have to be made in the rainfed sector as well
Can we use small scale supplementary irrigation to “insure” yields and increase productivity?
Public Health
FarmerLaborer
Consumer
Wastewater irrigation
Soil
Fodder
Ground water
Turn waste water into a valuable resource
LivestockMilk(Meat)
Rice Vegetables
Short term and Long term health impacts
REFORM WATER GOVERNANCE
• By demonstrating that evidence based policy and management works best
• By providing options for policies and institutional reform• By proactive policy development that encourages trade
in virtual water• By improved determination of water rights• By better valuation and pricing of water that protects the
rights of the poor• By improved management systems that are equitable
and gender friendly
Do we have the right incentives in place?
• There are major losses between storages and plant growth in irrigation systems
• There are many ways in which these losses can be reduced
• At the system level, government can recoup water by reducing leakages (but lost water often goes into groundwater and is subsequently used)
• At the farm level unless water is well regulated efficiency gains are often used to extend the area irrigated
• This may help food production, but it often does not lead to water going to the highest value users
The role of water footprinting
• Useful tool for understanding the impact of agriculture, urban areas or industry on the water resource base
• Needs to be coupled with active responses including productivity improvement, demand management, change in personal water consuming habits
• It may help industry make choices on how to organize supply chains that have the least environmental impact
• Ideally, footprinting information meeds to lead to policy responses that recognize the differential value of water from different sources (e.g maize grown in rainfed areas is more environmentally appropriate than maize irrigated from non-sutainable groundwater)
Changing the way we look at water
• We need to move to governance systems where water rights are defined, water can thus be valued/priced and trading allowed
• Similarly water allocations to users need to be established, regulated and policed to maintain use of surface and groundwater at sustainable levels
• Government could then buy back water for environmental uses, and urban and industrial users can buy water from agriculture
• This will provide financial incentives for all to use water wisely and to strive for productivity gains.
• Of course, the poor need their water rights defined and basic needs for drinking, washing etc would be separately identified
Trading Water
From this .... From this .... To this To this ……..
Based on WaterSim analysis for the CA
IF WE CAN CHANGE THE WAY WE DO BUSINESS WE WILL HAVE ENOUGH WATER
Today
CA Scenario
Practices like today
CA Scenario: Policies for productivity gains, upgrading rainfed, revitalized irrigation, trade
CONCLUSIONS
• No doubt that we have a water crisis• Given current projections of food and water
demand we can possibly avert future food crises• Ensuring availability of water for agriculture is
vital, but requires major productivity increases and underpinning water reform
• The impacts of climate change are still uncertain, but investment in adaptation to CC will also be relevant to the impacts of the other drivers of water scarcity
top related