Agricultural drainage has become a priority in agriculture and the economic development of the state. Algeria has launched several agro-economic projects pertaining to natural resources and human potential for development in agricultur-al areas. Our aim is to model the morphological evolution of open drainage channels, under the influence of sedimentary transport processes. The application of the Hydrologic Engineering Center’s River Analysis System (HEC-RAS) software is to examine two-phase mathematical models. In our case it is the flow and the sedimentary charge along a trapezoidal earth channel of a wetland north east of Algeria. The results of these models were validated by actual data obtained during the observation period from 2017 to 2018, for various rainy events. The solid transport and sedimentation velocity equa-tions of Engelund and Hansen and Van Rijn respectively used by this model, give Nash performance criteria equal to 0.95 and determination coefficient R2 equal to 0.91. On the other hand, the laying of a coarse gravel layer of median diameter of the grains d50% = 60 mm on the bottom of the channels reduces the rate of sedimentation by about 32% over an 11-year pe-riod. This satisfying objective study of the modelling allows to obtain an approach to the renovation and a plan for new design of drainage systems, that participates to the sustainable development in the agricultural field.
Surface water of Kébir Rhumel basin is indispensable for domestic and industrial needs of this region. Industrial development, with water excessive use and chemical products, in production and industrial treatment, and not sustainable ferti-lizers in agriculture, constitutes a serious threat to maintain our resources of good water quality. The majority of domestic and industrial wastewaters of the region, discharged to the stream water of Kébir Rhumel basin, promote the water enrich-ment in nutritious elements, phosphorus and nitrogen and particularly, the resulting increase in the aquatic primary produc-tion, mainly the planktonic or benthic algae. As a result, the physical and chemical properties of water deteriorate.
This basin allows construction of the largest dam in Algeria “Beni-Haroun dam”. The infrastructure that was one of the greatest challenges of Algeria is now a reality. Hydraulic complex of Beni-Haroun remains a strategic and major achievement in the development program of water resources sector. This enormous building was constructed in the territory of the Wilaya (province) of Mila, used to meet water needs, with four million inhabitants, of eastern Algeria and other neighbour-ing regions that have suffered from lack of water consumption, especially in summer. In addition, it will irrigate over 42 000 ha, going thus to the several plains.
Integration of sociological and environmental concerns into dams design is a recent phenomenon. It is considered at the impact study level, during which the dam study project is accompanied by a survey to assess project impact on natural en-vironment and socioeconomic development.