Water Accounting in Practice

As the agriculture sector represents 70% of water withdrawals, relevant agricultural water management and planning decisions must be based on good quality information and a sound understanding of the local context.

It is often assumed that investments in irrigation modernization will save large quantities of water that can be released for other uses including the environment, and water savings lead to increased productivity. This assumption underpins many of the existing lending programs by multilateral agencies. However, current studies into the validity of these assumptions are inconclusive, and there is a lack of evaluation of the impacts of high-efficiency irrigation systems at field and basin scales.

Water accounting fills this knowledge gap by providing quantitative estimates of the water balance (sources, diversions, withdrawals, consumption, return flows, changes to storage) and quantifies biophysical changes that result from different irrigation interventions. IWMI will engage in the further development of Water Accounting as a practical tool to guide investments in irrigation and more generally agricultural water management and to assess the impacts of these investments and evaluate water interventions decisions.

Objectives

• Promote the use of water accounting tools at multiple scales (from the field- to basin-level scales).
• Demonstrate their usefulness in supporting project investment and policy interventions.
• Enhance project-level outcomes for beneficiaries (this includes bringing water consumption within sustainable limits).

Project brief: Water Accounting in Practice