Water and society in the ancient Maghrib : technology, property and development

Abstract

The author attempts to show, first of all, how our approaches to the problem of water in the ancient Maghrib, both as natural resource and as property, have been determined by modern conceptions of political and economic development. Once this historical background to the problématique has been outlined, along with the biases it has imparted to the study of ancient hydraulic technology, a fresh beginning is made founded on the basic physical principles upon which the collection, movement, and allocation of water must have been made in ancient north Africa. The limited number of physical principles is assured both by the simple technology available at the time and by the fact that most of the agricultural land in the region (over 95 %) had to be served by these same basic techniques ever in our own time. Therefore, it is necessary to understand first how simple hydraulic systems function and develop before even beginning to deal with more complex problems of rural development in the Roman period. Two types of such irrigation systems are described in order to demonstrate their function within definable environments. These case studies are undertaken to show why some rural regions were open to agricultural development while others were not, given any possible application of a traditional irrigation technology, African or Roman. To measure the effects of a possible conscious alteration of traditional water control systems, the case of the concrete wadi dams of Tripolitania is investiated as perhaps the clearest example of the deliberate substitution of 'Roman' construction techniques for a traditional form of water control. Finally, the author attempts to provide a broader framework for the study of the use of different irrigation techniques in the development of African agriculture. A complex set of geopolitical factors, rather than a simple monocausal explanation of introduction by outsiders, is at the centre of this argument. The geographical elements that are crucial include the first principles governing the physical movement of water, local environmental conditions, and the nature of human response to these conditions. The responses throughout the entire southern Mediterranean arid zone are seen to have considerable similarity in type (though not in precise cause or chronology) as revealed by a number of 'fossil indicators' including extraordinarily high grain yields, wadi cross-walling techniques, and typical fortified-farm complexes. The advance and retreat of these irrigation systems is then seen to depend primarily on a combination of these historical-ecological conditions and generally favourable or unfavourable political environments, rather than on any consciously applied Roman imperial policy of agrarian development.