The agricultural sector has to compete for water with other users, such as industry. Food security does not just depend on how much water is available for growing food, but how efficiently it is used.

Research from the International Water Management Institute, Sri Lanka, and partners, examines how water used for  rice irrigation is managed in two sites in China, one in the Yellow River basin and one in Yangtze River basin.

In the Yangtze basin, water is relatively abundant, while the Yellow basin experiences water shortages. In both systems, the main user groups are farmers, irrigation operators, cities and basin managers. The researchers assessed various farm-water saving strategies to understand if and how water is saved.

In the Yangtze basin site:

• Water is stored in ponds and reservoirs close to users. Farmers order their irrigation water through user groups and village leaders.
• Important decisions, such as when to release water from reservoirs, are based on factors such as available storage and rainfall. These decisions are made at a high management level.
• The irrigation system is financially independent, with people paying for water.
• The irrigation system has successfully released water for non-agricultural uses, with only a modest decline in rice production. Farmers have learned to harvest more rainwater and  rely less on water from the main irrigation system.

In the Yellow basin:

• The Yellow River Conservancy Committee controls gates along the river.
• Water for irrigation systems is managed by the local government. Each irrigation system receives water based on availability along the whole river, and no water is stored near users. The irrigation department collects fees from people who use the water, but these do not cover operational costs.
• The pressures and incentives are different between users. The amount of water diverted from the river has been reduced to provide more water to downstream users, and farmers increasingly pump groundwater for irrigation to supplement scarce river supplies.

Perhaps surprisingly, the water-abundant Yangtze basin site has more water-saving activities. Managers and extension workers promote several ways to save water.

Despite water shortages, there are few efforts to save water in the Yellow basin site. Farmers have little incentive to save water; the pricing system means they have no reason to take less water than is offered. The poor supply of infrastructure and inefficient delivery also discourage farmers from trying to save water. However, little water is wasted because excess irrigation water on rice areas is used by people downstream pumping groundwater and drains. 

The researchers conclude:

• Policies and strategies for changing water use and management must aim to align the objectives and incentives for different groups, to obtain society-wide goals for improved water use.
• Policymakers must recognise that there is often no easy decision, because of the complex nature of water use. A change in use by one group impacts other users, requiring a basin perspective to understand the impact of various actions.
• Farmers often have to adapt to decreasing supplies, due to the allocation of water to other sectors. Farmers rarely drive the reallocation process by saving water and releasing it for cities.

Source(s):
This research was conducted by David Molden, Dong Bin, Ronald Loeve, Randolph Barker and T.P.Tuong, as part of a collaborative study with: Wuhan University; the National Centre for Irrigation and Drainage Development in China; the International Rice Research Institute; the International Water Management Institute; the Commonwealth Scientific and Industrial Research Organization in Australia. >
‘Agricultural water productivity and savings: policy lessons from two diverse sites in China’ Water Policy 9 Supplement 1, pages 29-44, by David Molden, Dong Bin, Ronald Loeve, Randolph Barker and T.P.Tuong, 2007

Funded by: Australian Centre for International Agricultural Research Project LWR/2000/030

id21 Research Highlight: 12 October 2007

Further Information:
David Molden
International Water Management Institute
PO Box 2075
Colombo
Sri Lanka

Tel: +94 11 2787404
Fax: +94 11 2786854
Contact the contributor: d.molden@cgiar.org

International Water Management Institute, Sri Lanka

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