Current Journal of Applied Science and Technology

The state of Qatar is a peninsular Arab country, as a small, hot and dry peninsula with an average rainfall of around 80 millimeters per annum, which is placed Qatar among countries of the lowest levels of rainfall in the world. There are no surface perennial streams in Qatar. Direct and indirect recharge from rainfall to the groundwater is the sole natural water resource in the country. The recharge takes place from the direct infiltration of heavy rainfall (>10 mm) through the fractures surrounding the water basins (watersheds) .Indirect recharge is the main recharge to groundwater  and it has a complicated mechanism which comprises run-off from surrounding catchments, ponding in depressions, evaporation from water surfaces and percolation of the remainder after the soil deficit has been satisfied.

The groundwater is considered the main natural water resource available for agriculture in Qatar; about 99% of the abstracted groundwater is used for irrigation. This continuous abstraction from groundwater leads to quality and quantity deterioration in the groundwater table and several production wells.

In 2007 the government has issued the ministerial decree No. 20 on “Rationalizing the use of groundwater and preventing its deterioration”  the decree banned the digging of new production wells to prevent this over extraction, in 2008 the Qatari government set its goals to protect and sustain its natural environment. The decree was amended and a proposed banning of the existing wells in the specific areas under a groundwater salinity of less than 2000 ppm for irrigating fodder crops, this amendment is intended to be a short-term solution till the issuance of the National Water Act.

This paper aims to review the current situation of water consumption for agricultural production and suggesting alternative water resources (Treated Sewage Effluent TSE with upgraded water quality) to comply with the decree No. 20. Gathering the available information and secondary data about TSE; agricultural production and environmental protection from governmental authorities and analyzed and presented in this paper.

The current total agricultural irrigated area, and water demand (excluding TSE) in the State of Qatar are 10,388 ha and 238 mcm respectively.

The Public Works Authority (PWA) has 3 main wastewater treatment plants plus other minor treatment plants that produced 634,860 m³ day^-1 in 2013, amount of 196,445 m³ day^-1 is in use for Roads and Expressways Irrigation, Local Landscaping Irrigation, Private Irrigation, Cooling, Industry (General) and Sand Washing. The remaining TSE volume 438,415 m³ day^-1 (50.4 million cubic meter), can be used for agricultural production after upgrading Treated Sewage Works (TSW) treatment plants to quadratic treatment using Reverse Osmosis (R.Os) which will cover about 21.3% of current agriculture water requirements. If all of the reaming volume of TSE will be available for Agriculture then above 95% percent of water demand by 2020 for agriculture will be covered.