Reuse of upland drainage waters has become an acceptable and common practice among many farmers who have no access to good-quality irrigation water, and suffer long periods of droughts in and and semi-arid regions. This study was carried out in a farmer's cotton field of 0.27 ha, located in the Eastern Mediterranean Coastal Region of Turkey, at 2.1 m mean sea level. The area presently lacking irrigation water has a typical Mediterranean climate with dry and hot summers, and cool and rainy winters. The farmers in the area use low-quality irrigation water, diverted from drainage channels, carrying irrigation return flows of upland fields. The objective of the work was to assess what effect the existing practice of irrigation can have on soil salinity using both conventional statistics and geostatistical techniques.