Possibility of using Sewage Effluent from Different Water Treatment Plants in Different Cities of Saudi Arabia for Agricultural Reuse

Abstract

A comparative study was conducted to test the efficiencies of 7 sewage water treatment plants, 4 in Jeddah, Bani-Malik, Al-Balad, Al-Khomrah, Hael, one in Makkah, one in Abha and one in Taif city in Saudi Arabia. The plants were installed for the treatment of the cities domestic and industrial wastewater effluent. The parameters studied included the physiological, chemical and biological characteristics treated sewage water (effluent) of the treatment plants. The 7 plants vary in their efficiencies to eliminate the studied parameters. The values of these parameters are within the range allowed according to the standards of the MWE ( 2005 ) and FAO ( 1985 ) except for the total coliform bacteria ( TCB ) which is high than the standards suggested (not to exceed 1000 colonies/100 ml), and also according to concentrations of TSS and according to concentrations of BOD and COD. So according to these results sewage water treatment plants working now in Saudi Arabia needed modernization to be more efficient in treatment of the raw waste water, so it can be used for irrigation and production of crop, fodder and vegetable plants. It is recommended to resort to treated sewage water for production of field crops, forages in general in Saudi Arabia.

Reusing Sewage Effluent in Greening Urban Areas: A Case Study of: Southern Jeddah, Saudi Arabia

“…According to [25], the pH of wastewater has a significant role in determining how readily available potentially toxic elements are to the plant, and how easily they dissolve in the soil. This result is in line with some earlier studies that established the alkaline composition of the effluent water stream in wadi Al-Khumra [26,27]. Plant growth is better at a pH of 7 or higher since all the nutrients of the soil become easily accessible at that pH value [28].…”

“…Therefore, it is acceptable to reuse this water to irrigate ornamentals and nonfeeding plants growing close to the sewage stream where the water samples were collected. These findings corroborate those of the authors of [27], who found that treated wastewater in some treatment plants in Saudi Arabia can be used to irrigate agricultural fields simply and safely in terms of pH, EC, inorganic solutes, and potentially toxic elements.…”

“…If their concentrations in the water exceeded the levels permitted for agricultural use, they would become harmful and would slow plant development. Advanced technical approaches, such as ionic exchange or the irreversible collision of salts, are used to remove these ions from sewage water [27]. In this investigation, none of the potentially toxic elements examined (Al, Cd, Cr, Co, Cu, Pb, Mn, Hg, Ni, and Zn) was found in concentrations above the permissible levels [37].…”