Evaluation of the suitability of surface water from Riyadh Mainstream Saudi Arabia for a variety of uses

Abstract An evaluation of the suitability of surface water for different uses from the mainstream running through Riyadh, Saudi Arabia, was conducted using three indices namely: water quality index (WQI), percentage of sodium (%Na) and Nemerow’s pollution index (NPI). The water samples were collected on monthly basis from June 2009 to March 2010 from 10 sites. The WQI was calculated based on different water standards for different uses. Excellent water has WQI value of 50–100, where WQI is calculated based on 29 parameters. The permissible range of %Na in water used for irrigation purpose should be between 40% and 60%. On the other hand, if 0