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Norwegian University of Science and Technology (2010)

Studies of the waterscape of Kilimanjaro, Tanzania Water management in hill furrow irrigation

Tagseth, Mattias

Titre : Studies of the waterscape of Kilimanjaro, Tanzania Water management in hill furrow irrigation

Auteur : Tagseth, Mattias

Université de soutenance : Norwegian University of Science and Technology

Grade : Doctoral thesis 2010

Résumé
The present study analyses the waters of Kilimanjaro Region, Tanzania, conceptualised as a waterscape constituted by material, institutional and ideational aspects. It draws on studies of the water management and the historical geography of hill furrow irrigation systems, based on 16 months of fieldwork.

Hill furrow irrigation systems are operated by groups of farmers who continue to use and develop long-standing traditions. Their practices and technology are of relevance to debates about indigenous intensive agricultural systems in Africa, concerning their emergence, sustainability and prospects for development. Groups of self-organised irrigators and their practices are targeted by several development initiatives, in water management seeking to control their water use, and in irrigation redevelopment aiming to replace existing technology and organisation. These concerns define the need for improved knowledge of the hill furrow irrigation systems of Kilimanjaro.

The main objective of this thesis is to contribute knowledge of water management and water use in hill furrow irrigation in Kilimanjaro Region. In order to achieve this objective, research proceeds along two lines of enquiry. The first concerns water management, where the study seeks to analyse and describe the operation, water use, tenure and management in hill furrow irrigation schemes by groups of farmers. The study seeks to analyse the ideas and implementation of initiatives in water management for the Pangani River Basin targeting these systems. The second line of inquiry is the historical geography of irrigation and changes in water use. Here, the study seeks to develop methods drawing on written and oral sources in order to examine changes in irrigation from a regional and long-term perspective. This will permit testing and reconsideration of dominant perceptions of hill furrow irrigation and its water history, and form the basis for a discussion of the explanation of change in irrigated agriculture.

I maintain that the approaches to water issues employed in this thesis and elsewhere can be analysed through different conceptualisations of the waterscape, encompassing not only the perception and representation of water issues, but also the material and institutional aspects of the waterscape. Aridity or water shortage does not speak for itself ; water problems and their prescribed solutions are situated knowledges of the waterscape, and are socially constructed within specific contexts. Material aspects are addressed as a question of how and why these systems have changed from a regional and historical perspective. This is relevant not only as a contribution to the study of the development of intensive agriculture, but also in order to test dominant perceptions of the hill furrow and its water history that are used to guide policy and interventions in hill furrow irrigation. Institutional aspects are examined as a question of the local organisation of these systems in terms of their operation, water use and tenure arrangements. Further, these aspects are addressed through the analysis of ideas, implementation and experience with water policy and institutional reform targeting hill furrow irrigation systems, influenced by global water discourse and actors.

The thesis consists of five research papers and a synthesis. The latter describes the methodological approach, which combines qualitative and some quantitative analysis of various forms of interview data with participant observation from fieldwork in rural Kilimanjaro and engagement with actors in the water sector through interviews, conversations and workshops as well as written sources. Approaches to the explanation of change in irrigation are reviewed and some implications for irrigation in the region discussed. Approaches to the organisation of irrigation are reviewed, demonstrating that this is an enduring theme in social science, related to broader debates about the institutions of society.

Working with an inclusive conception of institutions (and hydraulic tenure), the study describes how hill furrow schemes are organised, either through more formal groups, often with elected leadership, or through a neighbourhood and lineage-based model under the leadership of a furrow elder. The local organisation of water use according the latter type is examined through a case study, which describes it as embedded rather than a strong single-purpose organisation. Theoretical and methodological triangulation is applied, and the organisation studied at a normativeinstitutional level, but also in terms of interaction and access to water for different social groups.

A series of initiatives in water management for the Pangani River Basin came in the wake of a hydropower redevelopment project completed in 1995 led by the Norwegian Agency for Development Co-operation (NORAD). The initiatives were related to a wider water policy process in Tanzania. They drew inspirations from a global water management discourse, which is analysed in terms of the influence of ‘state-centred’, ‘market-based’ and ‘community-based’ approaches to improved water management, related to development ideologies. A strategy of river basin management was developed from the 1990s, seeking to establish water licences under statutory law as the only legitimate basis for access to water, to introduce volumetric water pricing as an instrument of demand management, and to curtail water use by the construction of ‘control gates’ in furrow intakes. The process of implementation is analysed as a meeting between a ‘modern’ water management system and an ‘indigenous’ water management system. It was characterised by non-cooperation and conflict, not only over water as a resource, but over norms of proper water management, such as over the issues of water pricing and custom as a basis for legitimate water use.

Change in irrigation as water use (and land use) change is addressed as a methodological and empirical question. Oral political history indicates the practice of irrigation in late 17th century Marangu, while the history of sedentary patrilineages as the central institution in irrigation management shows the expansion of the system in upland Marangu in the 19th century. The establishment of irrigation schemes in the 19th century can be related to dry season cultivation of finger millet, a crop that was phased out with the increase in agroforestry in the highlands and expansion of arable cultivation of maize in the foothills in the early to mid-20th century. Surveys made for administrative purposes and contemporary reports are analysed to test two hypotheses about changes in irrigation. The results show that the dominant understanding – that the extent of irrigation is a result of late 20th century increases in population – is false and needs to be moderated. A competing thesis of decline in irrigation fits the development only in limited areas and underestimates the dynamic vitality of the system. On the basis of this regional and long-term diachronic analysis, a hypothesis of restructuring is put forward, where a decline in the number of schemes in the densely settled highland areas since the 1930s has been offset partly by an increase in irrigation in new areas in the foothills and lowlands and partly by an increase in scale. It is argued that change in irrigation is not determined by a single factor such as population, but that technological change and the intensification process and changes in political economy (in terms of market, economic policies, and development planning) have to be considered.

Ideas of water are explored in terms of ideas of improvement in water management and local perceptions of water relevant to the operation of irrigation. The analysis suggests that the water management reform process is influenced by development ideologies in the global water management discourse as well as a national tradition that can be described as technocratic. Its implementation was guided by notions and interpretations of a water crisis. Local ideas of water management differ from those associated with the initiative, which in turn influenced how water management was contested.

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Page publiée le 20 janvier 2015, mise à jour le 7 octobre 2019