SELECTED CASE STUDIES
Themi River Basin, Tanzania
OPERATIONAL RIVER DISCHARGE MONITORING
As regional sub-branch of the Tanzanian Ministry of Water, the Pangani Basin Water Office (PBWO) monitors river discharge in the Pangani River Basin in northern Tanzania. Because of budget restrictions, among other things, the PBWO struggles with simple gauging tasks in the basin on a daily basis. On top of that, compliance monitoring of water abstractions by the numerous water users for irrigation is not possible in a comprehensive manner. This results in weak enforceability of the 2009 Water Resources Management Act that provides for an institutional and legal framework for the management and development of water sources in the country.
The iMoMo team partnered with PBWO to explore the potential of affordable and scalable crowd-sensing technologies to measure water flows in different settings and for different purposes.
Rufiji Basin, Tanzania
IRRIGATION ABSTRACTION COMPLIANCE MONITORING
Compliance with quota regulations for irrigation water abstraction is often hard to monitor and enforce for various reasons. First, in large basins with a great number of intakes, the establishment of a traditional monitoring network would result in significant installation and operations/maintenance costs. Second, vandalism regularly leads to the destruction of such networks which render investments futile.
Kasese, Western Uganda
IMPROVING ON-FARM IRRIGATION SCHEDULING
Irrigation scheme water allocation is often riddled with inefficiency. Water use efficiency is low and irrigation schedules, often of the fixed rotation sort, cannot effectively help in controlling soil moisture in an optimal way. Wastage of water and suboptimal crop outcomes result.
Jointly with the National Agricultural Research Organization and the Food and Agricultural Organization (FAO), the iMoMo Project team has helped to equip a smallholder irrigation scheme in Western Uganda with the mobile discharge measurement technology discharge.ch. Daily measurements for assessing water use efficiency and irrigation scheduling compliance as well as for optimizing allocation rules have helped to get a better understanding of how to improve scheme-level irrigation agricultural outcomes.
Manica Province, Mozambique
ESTIMATION OF FIELD-SCALE WATER AVAILABILITY
Irrigation systems are a common pool resource. When farmers fail to internalize the cost of their use on others, the allocation of water within the irrigation scheme may not only be inefficient but also affect water availability in the long term. Collective action over the management of a scheme is then necessary to ensure the sustainability of irrigation supply. Decentralized models of governance have evolved to formalize the delivery of water resources. Yet, local institutions like water user associations may not yield efficient resource sharing if the main constraint users face is limited knowledge of water management.
To understand the origins of irrigation management problems in central Mozambique, a World Bank Impact Evaluation team jointly with the National Institute for Irrigation, a group from Eduardo Mondlane University and the iMoMo team designed an intensive user-based water monitoring protocol. Plot-level water use data was collected three times per day for 146 consecutive weeks covering 159 plots in three irrigation schemes.
High-frequency time series were paired with household surveys on agricultural practices and production to understand sources of inefficiency in water allocation in a region suffering from low agricultural productivity and periodic droughts. This data system added to previous demonstrations of the feasibility of user-based systems for monitoring water management.