Components of Groundwater Balance for Tasuj Plain (North of Urmia Lake)

The Agricultural productions in the province of East Azarbaijan and especially in Tasuj plain located on the north of Urmia Lake is completely depends on groundwater resources. It is required to recognize the components of groundwater balance with relative precision for optimal and sustainable application of groundwater resources. Therefore, the present study was conducted with the aim of determining the components of charge and discharge of the groundwater balance for the Tasuj plain for a period of 23 years from 1994-95 to 2016-17. Results showed that average of groundwater charge in this plain was 20×106 m3 which input flow from the groundwater sections (with 39%), infiltration from rainfall (with 27%), infiltration from surface flow (with 12%), infiltration from irrigation water (with 18%) and infiltration from municipal and industries water (with 4%) played a major role in charge of ground water. The average groundwater discharge in this plain was 24×106 m3. Therefore, the average reduction in groundwater storage was 4×106 m3 per year. In other words, discharge from groundwater resources in this plain was higher than that of charge. Basic approaches to sustainable utilization of groundwater resources include increased charge or reduced discharge of ground water resources. Application of procedures for improving irrigation efficiency, land leveling, increasing infiltration from rainfall, surface runoff or irrigation water are some of the executive solutions to balance groundwater.