
Introduction
REWAS is an innovative tool designed for assessing water use and productivity in irrigated agricultural systems. Built for usability and transparency, REWAS is implemented in Microsoft Excel, allowing users to easily input data, evaluate scenarios, and generate actionable insights. From analysing irrigation technologies, agronomic practices, to changes in the spatial extent of irrigated areas, REWAS provides detailed water accounting results at both field and system levels.

Key Features
- User-Friendly Interface: Enter and analyse data for multiple scenarios, including reference conditions and up to five interventions.
- Flexible Data Inputs: Import data from field trials, remote sensing, or FAO AquaCrop simulations, ensuring adaptability to available information.
- Comprehensive Water Accounting for Agricultural Systems: Evaluate key water flows such as irrigation, crop transpiration, soil evaporation, drainage, and percolation at field and system levels.
- Customizable Parameters: Adjust irrigated areas and recoverable flow fractions for drainage and percolation to reflect specific basin characteristics.
Benefits of Using REWAS
- Evaluate Interventions: Compare the impact of different practices or technologies on water use, crop yields, and water productivity.
- Real Water Savings: Identify potential savings and estimate recoverable flows to rivers or aquifers for sustainable water management.
- Scenario-Based Insights: Visualize water balances with intuitive plots that dynamically adjust based on selected scenarios.
- Seamless Integration with AquaCrop: Import crop model outputs directly to streamline analysis and improve accuracy.
How Does REWAS Work?
- Input Data: Enter rainfall, irrigation, crop transpiration, and other water-related data manually or import results from AquaCrop.
- Set Parameters: Define the irrigated area and recoverable flow fractions for drainage and percolation.
- Analyze Results: Generate outputs such as water use (mm/season) at the field scale and volumes (MCM) at the system scale. Assess real water savings and water productivity.
- Visualize Outputs: Use intuitive water balance plots and dynamic arrow sizing to explore inflows, outflows, and scenario-based comparisons.
REWAS empowers decision-makers, researchers, and practitioners to make data-driven choices for sustainable irrigation management. By integrating diverse data sources and providing transparent calculations, REWAS is a trusted tool for water savings analysis and improving agricultural efficiency.
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