Hydrology and Best Practices for Managing Water Resources in Arid and Semi-Arid Lands

This chapter provides a critical analysis and evaluation of the water issues relevant to Kenya's ASALs. This has particularly been centred on the current resource development and management, future resource demand as well as extent of its vulnerability to climate variability and change. The water development policy interventions have also been evaluated. The analysis has revealed that water resources are being utilized to satisfy a myriad of demands and that in-fact a water shortage already exists in these ASALs. A number of factors including population pressure, poor resource use and management and other socio-economic activities have been noted to increase the vulnerability of the available water to the impacts of climate change. A raft of recommendations for purposes of ensuring the sustainable utilization of this vital resource has therefore, been proposed.

Towards Integrated Innovative Technologies for Sustainable Provision and Financing of Agricultural Groundwater in African Drylands

Water Vision 2000 declared: “Water crises are not about too little water... but about managing water badly such that billions of people and the environment suffer badly.” Good leadership and governance are therefore needed to bring about investments through innovation in the water sector. However, the ubiquitous nature of investments in water services makes it less attractive for the private finance sector. Agricultural groundwater development has particularly begun offering incentives for private investors. This study foresees a high potential in the integration of recent developments of information and communication technologies (ICT) with existing hydraulic technologies to sustain cropping and food production in African drylands. A case is given for the blending of the Bhungroo, Grundfos Lifelink and M-Pesa technologies to make an integrated BGM-P technology for agricultural groundwater supply. This will enable water users have access to the service at the “right” time, in the “right” quantities, at the “right” places. This is a pathway to sustainable agriculture intensification.

Water Allocation Assessment and Hydrological Simulation on Mukurumudzi River Basin in Kenya

Lack of water allocation plans in semi-arid river basins increases the risks of hydrological droughts. The Mukurumudzi river basin was experiencing extremely low flows which led to a water allocation assessment to quantify the available resource amidst competing demands from domestic, commercial and environmental needs. An abstraction survey was conducted along the entire length of the river followed by a low flow study and water balance modelling using rainfall-runoff Model. Observed flows at source and mouth were 0.028 m3/sand 0.043 m3/s respectively. Simulated flows estimated an environmental flow (Q95) deficit of0.023 m3/s and 0.010 m3/s in July and August respectively. Normal flow (Q80) of 0.190 m3/s and flood flow (Q50) of 0.520 m3/s were estimated. Compensating the environmental flow deficit in July and August was recommended. A more detailed hydrogeological study should be conducted to elucidate the potential of the groundwater resource in meeting current demands.

Effects of Irrigation Management Practices on Water Allocation Among Farmers in Kiladeda Sub-Catchment, Tanzania

Kiladeda River in Pangani Basin, Tanzania, plays a vital role of providing water for agricultural activities of the sub catchment. However, it is experiencing a problem of inequitable distribution of irrigation water among farmers. Cross-sectional data was collected from farmers both in upstream and downstream using questionnaires, while river discharge measurements were conducted in referenced spot gauging stations. WEAP model was used to analyze water demand and allocation among farmers. Furrow irrigation (94%) and plastic buckets (6%) were the main irrigation water management practices. The results of WEAP model revealed a water shortage of about 53.6% of the total irrigation water required. The annual irrigation water demand and unmet demand were 13.93Mm3 and 7.47Mm3 respectively, and are both expected to increase twice in 2020. This high water demand for irrigation could be the main cause of excessive water abstraction. A partnering approach is recommended to improve irrigation water management; reviewing of laws, regulations and water rights.

Kenya Success Story in Water Resources Management

Management of water resources is at the heart of political discourse to raise awareness among local stakeholders for support in policy formulation and implementation of water sector development plans. The concept of integrated water resources management (IWRM) has been largely disseminated by the Global Water Partnership. Though theoretically appealing and sound, the process of implementation of participatory water resources management still has potential to yield results at local level. One reason is that the top-down approach used is too broad to be implemented and neither does it facilitate better understanding of the needs of each sector involved in the inter-sectoral collaboration to foster planning and benefit sharing of water resources. It is in favour of such practical action for water sector planning and development at small scale catchment level that the concept of “light” IWRM or “Integrated Watershed Management” (IWM) was developed to reduce various threats and severe water constraints affecting local stakeholders.

Infrastructures for Data in the Context of Flow Forecasting Using Artificial Neural Network Model for Okavango River in Namibia

A number of evolutions on data collection and sharing have been published. Countries have collected data but lack of access and complexity to implement these technologies has limitations. HydroServer Lite a web based server for sharing water data helps to address the need of data sharing and storing in a standard format. Namibia Hydrological Services has no common online system for storing and sharing of water data. This study extends the research on HSL features as data system linked to online ANN forecasting model. This is done by implementing a Namibian HSL using real time connection to the database to operate in real time tools developed to visualize and fill in missing data. Lastly, a model was build using Waikato Environment for Knowledge Analysis. Results of the best model obtained are coded in Hypertext Preprocessor with near real time data to provide continuous forecast. Linking data system for water resource management in a standard format is practical and promising.

Probabilistic Studies of Hydrologic Drought Events in Juba River in Somalia

Juba River runs from its headwaters in Ethiopia through Somalia and discharges into the Indian Ocean near Kismayo. Severe droughts recur in Juba River Catchment. This chapter examines the time series of hydrologic droughts and the factors influencing their occurrence in the catchment. The Author further demonstrates the application of probability distributions to compute the exceedance probabilities of the hydrologic drought experienced in the catchment in the past, from 2001 to 2014. The fit of the probability distributions are compared to show the best fitting of all distributions. The probability distribution that will reasonably fit well to the data set is adapted to generate graphical plots for forecasting the return periods of drought events in the Catchment. Reconstructing past drought episodes and future drought predictions is useful in drought risk management in Baardheere region of Somalia.

Streamflow and Salt Flux in the Semi-Arid Tiva River Basin in Eastern Kenya

This chapter presents the results of a study on the influence of streamflow variability on salinity, total dissolved solids (TDS) and conductivity in a semi-arid Tiva River Basin in Kenya. Measurements of salinity, TDS, conductivity and river discharges were undertaken in sampling stations by applying standard hydrologic methods. The study shows that there is a significant relationship between the variability of streamflow and the variability of salinity, conductivity and TDS in the river. The high salt concentrations were a result of high evapotranspiration and seepage of subterranean water from bank storage and groundwater aquifers. Inter-sub-basin variations in the levels of salinity were attributed to differences in land uses, lengths and sizes of the sub-basins. Sustainable irrigation and land use practices in the semi arid Tiva River Basin requires construction of water reservoirs for control of salinity levels in the river.

Multi-Temporal Landsat Remote Sensing for Forest Landscape Fragmentation Analysis in the Yoko Forest, Kisangani, DRC

This study assessed the impact of human activities on deforestation and sustainability of water resources and livelihoods in the Congo Basin. It mainly aimed to assess forest degradation in the Yoko reserve from 1976 to 2015 and investigate the compatibility of Landsat imagery for forest monitoring. Digital Image processing for unsupervised classification was done using ENVI software while supervised classification was done by means of ArcGIS 10. Results show that forest landscape faced large scale human induced fragmentation over the last 40 years. If these trends continue, they will affect the sustainability of water resources and livelihoods in the Congo Basin of the Democratic Republic of Congo. Hence, policy makers need to look at key drivers and address impacts that may threaten the future of Hydrological Ecosystems Services, including water and land resources in the Congo Basin. Authorities have to apply an Integrated Management of Water, Land and Ecosystems.

A Spatial Database of Hydrological and Water Resources Information for the Nyangores Watershed of Kenya

Advances in environmental remote sensing have provided an opportunity to monitor water resource systems in vulnerable regions with data scarcity. The spatial datasets can be used to build spatial models of reality to enable derivation of catchment based characteristics, also often required by models in hydrology. The derived estimates can then be mapped and cartographically presented to support water resources planning within the concerned developing regions. This contribution presents a database of water resources information for an upstream catchment of the Mara River Basin of Kenya developed from freely available spatial datasets. Additionally, water quality parameters (pH, electrical conductivities and Total Dissolved Solids) selected as essential indicators of the suitability of the water resources for domestic applications were measured and mapped. The database, packaged as spatial maps, has been presented to the local stakeholders for developing appropriate catchment management strategies within the important watershed.