When the site conditions are favorable, the RCC dam finds its justification in multiple benefits: spillways easily combined with the dam, intensive mechanization of work reducing delivery times and its economic competitiveness (Zdiri et al. 2006). However, the great advantage of this type of dam is the integration of the spillways at the dam. This advantage gives a great opportunity at the relatively high flood sites. Thus, it can become competitive at the expense of other disadvantages: volume of the concrete, demands on the foundation deformation moduli, thermal stress, etc. (Goubet 1992). One of the best solutions for dams’ design is RCC (Roller Compacting concrete) due to its economic benefits and construction time. In comparison with conventional concrete dam, RCC dam can decrease the costs in ranging from 25 to 50 percent. Constructing the spillway in dam’s body is cost-effective comparing with the embankment dams that require using spillways in an abutment (Zarrin et al. 2016). In Algeria, the means of conventional surface water resource mobilization has always been oriented towards large dams. Nevertheless, time’s realizations of these structures (studies, realization, financing, etc.) have led to a gap between needs and demands. Under the pressures and tensions caused by persistent drought, the government has committed significant investments for the mobilization of surface water resources from small dams. These structures, of a height between 10 and 25 m, are, exclusively, intended for the purpose of irrigation of small perimeters areas. They are designed in clay, homogeneous or with central core. The spillways are isolated from the dams. The assessment of project flows by empirical models (no gauging of small watersheds) was the main cause of degradation observed on the spillways (Rouissat and Smail 2009a). The expertises carried out on twenty small dams in western Algeria showed that, in most cases, the recorded degradations are due to the inadequacy of spillway’s capacities (Rouissat and Smail 2009b). The reflection undertaken in this paper concerns the analysis of using roller compacted concrete (RCC) in design of small dams. Additionally, we propose a techno-economic analysis between the spillways designs of small earth dams, and those incorporated in RCC dam’s body. The development of this reflection was applied to the case of Khneg Azir earth dam in southwest Algeria. On the economical level, four variants were analyzed: earth dam with two types of spillways (lateral and frontal), fully submersible RCC dam and incorporated spillway on the dam. The design calculations carried out on the four variants have the objective of estimating the volumes of the works and consequently the costs of the various variants. On the technical level, and particularly the aspect related to the deformation of the foundations, a numerical modeling has been developed for different deformation moduli to judge the adaptation of the RCC dam type according to the quality of the foundations.