The term "Oasis" is used to express a natural phenomenon in desert areas. It is a low-lying isolated area surrounded by desert from each side. Siwa Oasis is a natural depression in Western Sahara, which has a low altitude of about 23 meters below sea level. It has an area of ​​about 250,000 feddans, of which about 209,400 feddans are cultivated and irrigated through a number of wells and springs. As a result of continuous and continuous flow of water in excess of 33 million m3 (Fathi Hammad, 2001) , In the absence of an efficient and efficient sewage system, in addition to the low efficiency of the existing drainage system, the water accumulation and accumulation of water in the low areas of the oasis has created a number of lakes, causing the problem of rising water level, Negatively affect their productivity and threaten the entire ecosystem of the oasis.
The study aimed to identify the most important returns and costs that affect the cultivation of jatropha and the economic feasibility of planting them. The research relied on both descriptive and quantitative methods. The results proved an IRR of about 27%, which is higher than the opportunity cost available. For the investment in Egyptian banks for 2018, which is an interest rate of about 17%, and the rate of return on costs was estimated at1.6 and the net present value (91025.6),
The study recommended the exploitation of agricultural waste water economically as a waste resource causing many economic and environmental problems and encouraging investments in this field.
dunes, and the provision of new jobs by increasing the areas of new land, and recommended the research the need to exploit agricultural wastewater economically as a waste resource causing many economic and environmental problems and encourage investments in This area.