Sulphates Suggested Guide Groundwater Quality for Irrigation, in the Eastern Regions of Nineveh Governorate.

The quality of the water used for irrigation depends on the total amount of dissolved salts, their species soil properties, and crop type. One hundred thirty-nine samples were taken from wells in the east regions of Nineveh Governorate to analyze their physical and chemical properties. Wells water was assessed for irrigation purposes based on the following guides; (SAR), (BSRC), (SSP%), (PI), and (KR). The results showed that the suitability of water for irrigation use that nearly (97%) of samples was excellent based on (SAR) and (BSRC) guides. While the suitability of wells water was (47%) based on (SSP%) guide. Also, the results show that (68%) of wells have good permeability for the PI index and (96%) are suitable by (KR) guide for irrigation. According to the hydrochemical investigation, modified quality facies (R3) have been suggested where (Ca-SO4) is the dominant species This guide was developed based on sulphate as one of the important irrigation criteria in the study area. The results of the application of this index show that (11%) are excellent, (26%) good, (45%) are suitable, (15%) doubtful, and (3%) are unsuitable.