Water resources and water management in North East Nigeria

Abstract

This thesis addresses some aspects of shallow groundwater resources, and the wider issues of water resources use and allocation, in the Yobe river basin, north east Nigeria. The studies reported here were carried out in the context of a research linkage, between a Nigerian and a British _University, set up explicitly to support a large rural development programme. This is probably the first time strategic academic research and regional development have been linked on such a scale in the region. ' Despite significant investment in the past in irrigation and other water resource developments, basic data on land and water resources, and their present use, are limited. Short term studies by Consultants have proved to be no substitute for long term routine monitoring, together with good natural and social science research. « 4 Priority research needs are identified in the sciences of climatology and hydrology, and in the use and management of water in the region. There is very limited knowledge of climatic and hydrological change over the last few decades, and almost total ignorance of the existing ' water uses, their economic value, and the efficiency or otherwise of traditional water management practices. The main issues addressed in the thesis are (i) the shallow groundwater resources of the Manga Grasslands, a upland dunefield, and the Yobe river valley floodplain or fadama, and (ii) the allocation of water resources, especially in the context of large irrigation demands. _ The thesis is presented in the form of six papers -(5 published, one submitted for publication), with a extended introduction (Chapter 1) and a short conclusion (Chapter 8). The main findings and conclusions of the work are that: (i) groundwater recharge to the upland is almost certainly much larger than present abstractions; (ii) groundwater recharge to the floodplains is small compared to present regional shallow groundwater abstraction; (iii) development of shallow groundwater resources for irrigation in the Manga Grasslands would be most inadvisable because of resource limitations and salinity hazards; (iv) limited development of small scale irrigation, together with careful monitoring and modelling should go ahead in the Yobe fadana; (v) the remaining questions concerning the mechanisms and magnitude of groundwater recharge throughout the region need to be resolved a a matter of urgency; (vi) water allocation policy can be developed rationally, based on clear objectives and criteria, a good research base, and transparency of motive.