Remote Sensing and District Database Programs for Irrigation Monitoring and Evaluation at a Regional Scale

This study develops an approach aimed at improving the capability of regional irrigation monitoring and evaluation to identify relevant factors and subareas influencing irrigation performance. Its objective is to contribute to improve the productivity of irrigable areas in a cost-effective manner by overcoming the lack of sufficient updated field data observed in conventional remote sensing studies. To do this, several performance indicators are calculated and analyzed by combining remote sensing with district database programs that irrigation districts use in their administrative and water management tasks. This approach was applied in Riegos del Alto Aragón (Spain), a large (124,596 ha) and heterogeneous project divided into 53 surface and sprinkler irrigation districts. The 2004 and 2005 seasons were analyzed, with the latter showing a severe water shortage. Under no water scarcity, most districts applied higher relative water supplies regardless of irrigation systems and other factors. Cropping patterns were less intensive in surface irrigation districts regardless water availability. Six districts and four main factors were identified as those most important to bridge the economic gaps that this performance implies.