Siwa Oasis : actions for a sustainable development

If in other geographical contexts, sustainability is an aspiration, in the oasis it is essential to survive. In this context, the dialectic man-soil is a fight, that does not require titanic interventions, but daily adjustments to compensate the challenges of nature. When the sand advances, the daily maintenance brings it back over the barriers. The big interventions of modernization, set out by the burocrats of the far capital, although spurred on by good intentions, seriously damage the oases. For example, the introduction in modern times of deep forage devastates the balance of the oases, producing a huge quantity of sewage, that collected in the low areas, has increased the saltiness of the soil, taking away hectares of precious agricultural lands. On the contrary, the interventions on a small scale, carried out with a adeguate knowledge of the context, are the only solution for the oases. So, sustainability is not considered as highly wasteful technological acrobatics to compensate wrong planning actions or the adoption of improper materials, but it is considered as development related to the real needs following the principle of maximum efficiency and complete metabolization of current technologies, before introducing a more advanced one. The use of natural materials such as land, rock, brick and wood are a good encouragement for a sustainable architecture. This is what the Politecnico of Bari tried to do in this study about the hill of Shali, in Siwa oasis, within the “Regional Cooperation Support Program” - APQ (Framework Program Agreement) South Mediterranean Area – Line 2.4 DIALOGUE AND CULTURE- Integrated project DIARCHEO - SUB-PROJECT SIWA Guided by a solid scientific method, that dates back to the teaching of the typological school, we have first of all analyzed with manual and topographical measurements the building structures of the settlement, conscious that the time spent in the survey allows a habit with the structure, that exceeds the impressionistic analyses. According to the continuity with history, the following process has worked either in the open and abandoned spaces after numerous collapses, with the aim of sewing up and restitch the building fabric, or in the building structures, proposing, in some cases, a scientific restoration with traditional techniques and materials, as in the case of the mosque, or the reutilization and rehabilitation of the houses, in respect of the functions and the local building traditions. The integrations with new building units have imposed the use of typologies coherent with the previous ones, but with the introduction of some innovative aspects, in order to respond to the requirements of society. The choice of using the karsheef cannot help being tempted to consider some shortcuts, represented by some modern, disguised and “antiqued” technologies in reinforced concrete, has imposed a scientific research on the properties of this material, that revealed very efficient responses to the climatic conditions in Siwa. This has imposed some changes in the building technologies in order to make the construction faster and cheaper.