"More Crop Per Drop" - Moving from "Dry" to "Wet" Water Savings

Historically, water management for agriculture was equated with the development and operation of water systems and structures, largely for irrigation. However, the rapid growth of urban centers and industry has led to increasing competition for water across sectors. Thus, the key challenge now for agricultural water management is achieving "more crop per drop"–an approach that marked a paradigm shift in IWMI's thinking on how to increase food production for a growing population, while simultaneously meeting the water quality and quantity requirements of other economic and environmental sectors.

Irrigation management has been at the core of IWMI's research agenda since the institute's inception in 1984. Research initially focused on the operation, maintenance and efficiency of irrigation systems at the field and system scales. In response to the need for increased food production, the IWMI Theme "Integrated Water Management for Agriculture" changed in the mid-1990s, when strategies to improve the productivity of water for food and livelihoods became the central focus.

IWMI Research Report #1, The New Era of Water Resources Management from "Dry" to "Wet" Water Savings (Seckler, 1996) represented a major change in the Institute's overall view of water management: from one previously focused on system level analysis to a more holistic, basin scale approach. IWMI began to place irrigation management into the overall context of river basins and to examine the interlinking hydrologic, socio-economic and environmental aspects of water management at multiple scales.

The overall focus changed from improving water management from the traditional agronomic perspectives of higher yields and higher total production (land productivity) towards water productivity, where the focus is on improving the output from each unit of water used. IWMI's slogan therefore became "more crop per drop". In more recent times, "more crops per drop" has become an essential part of the larger picture in the valuation of water and its use. Following from this shift, IWMI pioneered the change in thinking from yields per hectare to yields per cubic meter. Further, the concept of water productivity is now widely used in both scientific and popular writings, and measuring water productivity has become a standard when assessing water management performance, be it at field, system or basin level.

IWMI's Basin Paradigm

IWMI's Basin Paradigm, spearheaded by Dr. Seckler, focused on four implications of moving from irrigation system level to basin level

• The importance of knowing whether basins are "open" or "closed".
In open basins, there are unused or unallocated flows out of the basin, while in a "closed" basin all water is already used for environmental or human consumption, and there are no further utilizable flows out of the basin. The concept of "open" and "closed" basins helped in determining which management strategies were most suitable.

• The importance of understanding the recycling of water within river basins.
While individual irrigation systems may be "inefficient", recycling along the length of the basin may re-capture losses, leading to high levels of basin efficiency.

• The effect of scale on the interpretation and importance of water use efficiency.|Finding ways in which water can be managed at all scales can enhance water productivity. IWMI's work helped develop practical tools for implementing and measuring water use Efficiency.

• The need to look at longer term trends in water supply and demand.
Much of the water used by humans is for agriculture. Therefore, water management practices need constant improvements to meet food targets with increasingly stressed water supplies. Within this broader framework, IWMI's research over the past 10 years focused on three key areas:

(Hussain et al., 2003); and water saving techniques (e.g., Barker et al., 2001).

Integrated Land and Water Modeling

Complementing IWMI's work on water management concepts and tools has been the development of modeling and analysis tools for improved water management at the Basin scale. IWMI has developed an approach to modeling that now enables researchers to study the interactions between different water users within a basin. One high impact product developed by IWMI is a global water scarcity map, which contributed to the World Water Vision (Cosgrove and Rijsberman, 2000). Further, modeling efforts together with in-house GIS and Remote Sensing expertise have supported the development of a suite of decision support systems for water allocation and management at a variety of scales (see e.g., Bastianssen et al., 1999; Droogers and Kite, 2001).

Operation, Maintenance and Management of Irrigation Systems

Finally, IWMI continues to examine irrigation system management for opportunities to improve performance, flexibility and reliability (e.g., Sakthivadivel et al., 2001). Almost all of IWMI's research on irrigation operation and management has revolved around the issue of level of service. This "level of service” concept accepts that users have a major stake in how water is allocated and delivered and that operation should be structured so that users are satisfied With the performance levels. IWMI's research generally concludes that there are no technical fixes that can overcome the lack of adoption of better service orientation and integrated technical, institutional and governance approaches are required (Research Report 17).

 

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