Climate Change and Water:Impacts & Management Needs

气候变化与水资源：影响与管理需求

Roger Calow

Water Policy Programme, ODI罗杰

Overview概述

1. The big picture概括1. Irrigation – surface water

systems灌溉—地表水系统3.Irrigation - groundwater

economies灌溉—地下水节约4. Conclusions总结

The most vulnerable?最脆弱群体？

Drivers of change & management challenges

变化动因 & 管理挑战Major drivers?

主要动因？…urbanisation, industrialisation, consumption...with climate

change overlay

A water ‘crisis’? 水危机？…who gets what (Q, Q, R) in a variable climate: farms vs

cities, upstream vs downstream, environmental vs human

Adaptation challenge? 适应挑战？…mediating between competing claims: range of different

scales

Agricultural futures? 农业未来？...agriculture will lose water. How? Impacts on poorer

households?

Agriculture & irrigation农业 & 灌溉

Two stories: • Surface water irrigation (IDs)

– Development - state sponsored, driven– Management - increasingly commercial

• Groundwater irrigation– More recent, increasingly farmer-led &

opportunistic– Boreholes 1949 (0) – today

(>5M)...concentrated in water scarce north– Controllability, affordability...impacts

Water withdrawals in Hebei by sector, 1990 – 2003

河北省分部门采水量

0

20

40

60

80

100

120

140

160

180

Surfacewater

Groundwater

Surfacewater

Groundwater

Surfacewater

Groundwater

Surfacewater

Groundwater

1990 1995 2000 2003

Wat

er w

ith

dra

wal

(m

cm)

Other

Agricultural

Municipal

Industry

Source: Hebei provincial WRD Statistical Yearbooks

Yellow River flows 1956-2000黄河水流量

0

200

400

600

800

1000

1200

1956 1960 1964 1968 1972 1976 1980 1984 1988 1992 1996 2000

Volu

me

(108m

3)

Year

Prov. QH SC GS NX IM SA SA HN SD HB Tot

Alloc. 1.4 0.1 3.0 4.0 5.9 3.8 4.3 5.5 7.0 2.0 37

Yellow River Allocation Plan （ billion m3 ）

Water allocation in the Yellow River Basin 黄河流域水资源配给

Permit 1 Hangjin ID: 0.41 bcm

Permits 2&3 Hetao ID: 4.77 bcm

Defined under the YRCC’s Water Allocation Plan (long term) and adjusted under Annual

Regulation Plans (annual)

Defining and protecting farmers’ rights?

Irrigation diversion 灌溉

Water allocation – basin to household

水资源分配—从流域到用户

Basin Allocation

Agreeme

nt

Province

QH SC GS NX IM SAA SA HN SD HB Total

Alloc. 14.1 0.4 30.4 40.0 58.6 38.0 43.1 55.4 70.0 20.0 370

Hangjin Irrigation District

280GL （ abstraction)

Hangjin Irrigation District

280GL （ abstraction)

Hetao Irrigation District

Hetao Irrigation District

Abstraction

permits

Water User AssociationsWater User Associations

Water User AssociationsWater User Associations

Channel Losses

Channel Losses

Other usersOther users

Group water

entitlements

Water certificate

s

HouseholdHousehold HouseholdHousehold

Hangjin - channel lining夯井—分渠灌溉

Channel lining and water transfer: winners…and losers?

分渠灌溉与水资源转移：赢家与输家？

Mugan Balahai Jianshe

Gross permit before trading410 mcm

Return flow before trading35 mcm

Saving after trading130 mcm

Return flow after trading35 mcm

Gross diversion after trading280 mcm

Water Permit of 5860 mcm

Water diverted before trading 375 mcm

Water diverted after trading245 mcm

Key messages – IDs & water transfers关键点— IDs 与水资源配给

1. Irrigation will lose market share

2. Supply will fluctuate...variability will increase

3. Deepening rights reform (basin to farmer) will grow in importance

4. Protecting the interests of poorer households as water is reallocated will depend on:

– Informal claims (WUAs, contracting)– Sound science – basin efficiencies, consumptive rights– Willingness to recognise effects on ‘3rd parties’ &

environmental flows

‘Water & Agricultural Management in Hebei’河北省水资源与农业管理

Total water withdrawals in Bashang counties, 1995 – 2005坝上县水资源抽取总量

0

1000

2000

3000

4000

5000

6000

7000

Surface

water

Ground

water

Surface

water

Ground

water

Surface

water

Ground

water

1995 2000 2005

Year

Wit

hd

raw

al (

m3

x

103

)

Zhangbei

Guyuan

Shangyi

Kangbao

Source: personal communication, Zhangjiakou City Water Affairs Bureau 2005.

Groundwater level changes recorded for three Bashang counties, 2003 – 2005

地下水水位变化记录

Source: Zhangjiakou City Water Affairs Bureau, 2006.

Predicted groundwater level declines in the Bashang

可预测地下水位下降情况

Source: WAMH 2004. Note: drawdown modelled over a 10 year period based on 2003 estimates of groundwater abstraction and recharge.

Irrigation development and control areas in the Bashang

Control areas - well drilling in the Bashang

控制区—井水抽取

Groundwater management challenge地下水管理挑战

Country Annual groundwater use (km3)

No. of groundwater structures (million)

Extraction/ structure (m3/year)

% of population dependent on groundwater

India 185-200 20 9,000-10,000 55-60

Pakistan 45 0.5 90,000 60-65

China 75 3.5 21,500 22-25

Iran 29 0.5 58,000 12-18

Mexico 29 0.07 414,285 5-6

USA 110 0.2 555,000 <1-2

Source: Shah, 2004

WUAs & quotas

In the long-term: 长期 Scale-up to reduce free-riding

Tie quotas to variable shares of aquifer safe yield

Progress: 进展Shared allocationsConservation incentivesDevolved management

A farm economy? 农业经济？

Shifting livelihoods生活水平变化

• Rural jobs – RNFE, migration• Rural incomes – diverse, dispersed• Dependence on CPRs - declining• Drivers of change – small push, big pull• Sources of vulnerability – income shocks• Nature of community – boundaries blurring• Rural development narrative – income,

employment

Vulnerable are locked in to the ‘old’ economy

Key messages – protecting high value aquifers & services

主要信息—保护高价值地下蓄水层 & 服务• Groundwater access – key role in poverty

reduction• But monitoring patchy, numbers uncertain, impacts

of climate change unclear • Protecting the interests of poorer households will

depend on:– Extending access to GW irrigation– Prioritising domestic water– Protecting key reserves– A different approach to management…devolving tasks

and functions…supported by sound science

Adaptation & development适应与发展

Conclusions结论

• Adaptation as development 发展型适应

• Climate as one pressure… 气候压力

• Agriculture as a water bank 农业 = 水资源银行

• Rural households as winners & losers…who are the losers?

• 谁才是赢家与输家？

Thank you

谢谢Beijing, February 2010

r.calow@odi.org.uk

www.odi.org.uk\wpp