| Abstract |
The objective of the study was to find alternative and additional water resources to develop marginal desert lands of west delta of Egypt and to allow safe and economically responsible reuse of treated wastewater from the city of Alexandria through agriculture. In order to achieve these goals a detailed survey for 74000 feddans(one feddan=4200 m2) in Alexandria catchments was studied. During the study the area was classified
to three categories according to the farm size to represent the range of farm types in the development area (small medium and large farms). The overall cropping pattern for the command area and the cost of the tertiary and on-farm irrigation systems (surface and drip), other infrastructure and equipment and all operating and maintenance costs were calculated. The results showed that the total capital costs of the treated wastewater conveyance system scheme are estimated at USS 394 million, with annual operating and maintenance costs of USS 40 million. The average annual net return per feddan was much lower on the small farm than the other models because of the less capital-intensive semi-commercial farming system adopted. Nevertheless, perennial crops (fruit trees and fuel wood) represented an important contribution to profitability and if these perennial crops are excluded from the cropping pattern then the FIRR(Financial Internal Rate of Return)falls to less than 0 %. Overall, the project would have an EIRR (Economic Internal Rate of Return ) of 7.6%. Despite the relatively high capital cost of the project and the high operating and maintenance costs necessitated by the need to lift pump the treated water several times during its conveyance to the project area and the predominant use of expensive trickle irrigation systems, the economic performance is reasonable. The major contribution to the benefits is obtained from the industrial tree crops to produce high quality tropical hardwood and/or wood for fuel or pulp and they make up over half of the predicted irrigated command area and produce over 70% of the benefits. Without forestry, the scheme would be uneconomic. In conclusion, the study showed that treated wastewater re-use can significantly contribute to national development schemes. [authors abstract]
|
