Water Issues in South Asia Need for a New Water Strategy

Tushaar ShahInternational Water Management Institute

www.iwmi.org

Highlights• Monsoon climate: all rainfall received in 100 hours of rainfall. Need for storage and

irrigation is paramount.

• Most densely populated areas of the world since 2000 years ago.

• Three Phases in the history of irrigation development in South Asia: • up to 1800• 1800-1970• 1970-today

• South Asia as the world’s largest user of groundwater

• South Asia’s groundwater challenges

• Short-term responses

• Long term answers

Era of adaptive irrigation-upto 1830

• Community was the unit of irrigation management

Rainfall and Soil moisture

Flow irrigation from tanks, canals, rivers

Lift irrigation from wells and surface sources

% of water consumptively used in agriculture

% Contribution to aggregateFarm output and incomes

Era of canal construction-1830-1970

• State emerged as the architect, builder, manager of irrigation

Soil moisture management

Flow irrigation from tanks, canals, rivers

Lift irrigation from wells & surface sources

% water consumptively used in agriculture

% Contribution to aggregateFarm output and incomes

Era of atomistic pump irrigation-1970-todate

Individual farmer as the irrigation manager

Soil moisture management

Flow irrigation

Pump irrigation fromwells, tubewells, canals

% of water consumptively used in agriculture

% ContributionTo Farm output & incomes

South Asia is the world’s largest userof groundwater in agriculture in the world.

0

50

100

150

200

250

300

1940 1950 1960 1970 1980 1990 2000 2010

cubic

km

/ye

ar

US W.Europe SpainMexico China IndiaPakistan Bangladesh Sri LankaVietnam Ghana South AfricaTunisia

India’s annual groundwater

use

India, Pakistan, B’deand Nepal terai haveover 23 million irrigation wells. We a0.8 million/year.

Every fourth cultivatoowns an irrigation wenon-owners depend groundwater markets

Each dot represents

5000 irrigation

wells.

Dams, tanks and canalsAre declining in significance.

These can not provide Reliable irrigation Around-the-year..

South Asia’s Water Challenges• Revitalizing surface storages

and canal systems.

• Groundwater depletion in western and peninsular India, and Baluchistan in Pakistan

• Secondary salinization in Indus Basin

• Arsenic contamination of groundwater in Ganga basin

• Fluoride contamination in hardrock aquifers

• Urban groundwater depletion

Source: “Down to Earth”

Implications: Wake up to new realities.

• Recognize and respond to the new reality. Government’s role as irrigation provider is no longer the most critical.

• Investing in surface irrigation is throwing good money after bad.. To survive, it needs to be reinvented.

• In Indo-Gangetic Basin, conjunctive management of surface and groundwater is key to improved water environment.

• In hard-rock India, we need a new monsoon strategy. Use the monsoon to recharge parched aquifers rather than just growing a crop and filling reservoirs.

• Groundwater recharge needs to be the new mantra of monsoon management in hard-rock India.

Long term answers: Ease the non-point environmental stress

Indo-Gangetic Basin: Rising population pressure on farm lands

Source: Sikka, A., et al. 2003. Draft report on Indo-Gangetic Basin Profiles.

18801920

1970

1980

1990

00.05

0.10.15

0.20.25

0.30.35

0.4

1860 1880 1900 1920 1940 1960 1980 2000

hect

are

Land: man ratio (ha/farming population)

The root cause of Water-stress in South Asia

Is population pressure On agriculture.

Rapid economic growthAnd moving people

Out of farming is the Long term answer.

Thank You.