Improving Spatio-Temporal Rainfall Interpolation Using Remote Sensing CCD Data in a Tropical Basin

This chapter looks at how interpolated annual and monthly rainfall variation can be improved by developing a geostatistical model that uses remotely-sensed cold cloud duration (CCD) data as a background image for a typical tropical basin, the Rufiji basin in Tanzania. We explored the Kriging model and its variants, and found it to be a good estimator in spatial interpolation mainly due to the inclusion of the non-stationary local mean during estimation. Model parameter sensitivity analysis and residual analysis of errors were used to test model adequacy and performance. They revealed that the parameter values of the variogram namely, the nugget effect, the range, sill value and maximum direction of continuity, as long as they are in acceptable ranges, have low effect on model efficiency and accuracy. Instead interpolation was found to improve when remotely-sensed CCD data was used as a background image as compared to estimation using observed point rainfall data alone. This improvement was revealed in terms of the Nash-Sutcliffe model performance index (R2). Although Kriging model application seems to be data intensive and time consuming in nature, it results in improved spatio-temporal interpolated surfaces so long as interpolated results can be interpreted with confidence and with prudent judgement of the model users.

Using Geographic Information System to Infollow the Fertilizers Pollution Migration

In recent years, many countries have faced great challenges due to their limited water resources. According to these challenges, they have undertaken large scale projects to reuse agricultural drainage water in irrigation purpose. The Governments in these countries can enhance water management and sustainable development by adopting policies that enable them to meet water demands and supply management. Therefore, there is a need for unconventional methods to provide better tools for the assessment and management of water quality problems to adopt management policies and set the limits for sustainable drainage water reuse. The implementation of Geographic Information System (GIS) in this field offers an ideal tool for measurements with limited number of sampled points. Statistical analysis that can be provided within GIS is rapidly becoming an impressive tool for statistical analysis of continuous data. The main objective of this chapter is to discuss using GIS to in-follow the pollution caused by fertilizers migration to the water and the soil by applying statistical analysis within the GIS using geostatistical analyst. Geostatistical analyst is an extension of Arc Map™ that bridges the gap between geostatistics and GIS and provides a powerful collection of tools for the management and visualization of spatial data by applying Spatial Statistics.

Application of Remote Sensing Technologies and Geographical Information Systems in Monitoring Environmental Degradation in the Lake Victoria Watershed, East Africa

Accurate information on the state of water resources in the Lake Victoria watershed is crucial for planning and sustainable development in the East African region. This region largely depends on its natural resource-base for economic development, and therefore comprehensive information on its resources dynamics is key in implementing poverty alleviation strategies, improving human condition and preserving the biological systems upon which the region‘s population depends. This chapter focuses on key issues, which have emerged as a result of population growth and development in the region. The research on which this chapter is based aims to address the concerns on land use and settlement trends in the study sites, vulnerability of the communities to water stress and sustainability of the livelihood systems in the watersheds of Nzoia River Basin (Kenya), Nakivubo Wetland (Uganda) and Simiyu River Basin (Tanzania). These communities engage in unique land use practices that have intensified environmental degradation in recent times. The research adopts a multi-disciplinary approach in bringing to the fore the various processes affecting watershed resources use and management in the selected wetlands of the Lake Victoria Drainage Basin (LVDB). The data presented covers trends in vegetation cover loss, pesticide pollution and general water quality parameters. Geographic information systems (GIS) and remote sensing techniques were employed to unveil land use patterns that have resulted in the degradation of the watershed. Wetland degradation levels have been characterized using secondary data generated by analytical techniques. New emerging challenges of environmental degradation caused by industrial, domestic and agricultural activities are presented and discussed. The potential of the new science of hydroinformatics in integrated watershed management through mathematical modeling, geographic information systems analysis and water supply management is highlighted.

Determination of Retention Efficiency of Kimondi Wetland in North Nandi District in Kenya

Wetland buffers may play an important role in the retention of nitrogen (N) and phosphorus (P) which are released in large quantities from agricultural, municipal and industrial sources with run-off from agricultural lands being a common source of such nutrients to wetland ecosystems. Wetlands receiving crop field drainage are shown to lower nitrogen and phosphorus in water of such ecosystems. The main objective of the study was to determine the retention efficiency of Kimondi wetland in terms of nitrogen and phosphorus. Results of the study show that it the wetland has mean retention efficiency of 90% and 95% for nitrogen during rainy and dry seasons respectively and mean retention efficiency of phosphorus of 80% and 93% during rainy and dry seasons respectively an indication that the wetland has high retention efficiency and its buffering ability has not been exceeded in both seasons.

A System Innovation-Oriented Integration of Management Information Systems in Urban Water Management

The scarcity of water resources exhibited in different parts of the world and the dysfunctional consequences associated with urban water processes and services are encouraging countries to adopt transformative innovative thinking. The movement from the “visions” of urban water management to ‘actions” demands more emphasis on the development of relevant platforms and frameworks that enable effective transitions and sustainability of actions and good practices. Within the context of a changing environment, urban water management processes need to be “shifted” from the “conventional” approach to a wider context capable of addressing the growing urban water management lock-ins. Complexities in urban water management originate from the difficulty of maintaining sector-based balances (mainly supply-demand balances) governing internal functionality as well as from the intensity and uncertainty of the dynamics of both the entire water system and the wide range of change agents interacting in its external environment. Such lock-ins are affecting the capacity of urban water managers and policy makers to develop suitable strategies and implementation pathways and improve the overall resource utilization and service provision capacity and efficiency. While conventional approaches continued to be widely used to address such lock-ins, little improvement tend to be gained with regards to the dynamics of the “problem domain” and the feasibility of “solution spaces”. Over years, emphasis continued to be on advocating “nesting” urban water management processes into the context of integrated water management, but without ensuring the availability of relevant change management strategies, tools and agents. Issues relating to water governance, decentralization of water management processes and authorities, involvement of stakeholders, development and adoption of appropriate information platform, and capacity building are moving to the front line agenda of urban water managers and policy makers. In the absence of relevant tools and integrated frameworks, the capacity of conventional urban water management approaches to address such a new context remains questionable. The complexity exhibited across the entire urban water subsystem (both in scale and magnitude) calls for not only the development on new or modified “program sets” but also transformed and enriched ‘mind sets”. Such migration can be envisioned through the adoption of system thinking, innovation and strategic niche management. This will improve the capacity of the overall urban management “sub-system’ to orchestrate its functionalities with the overall water system using a holistic approach. This contribution focuses on the imperativeness of capacity building in urban water management in a changing environment and the importance of developing sustainability framework and approach in accordance with the principles of system innovation and thinking.

Science and Water Policy Interface

Despite many advances in the field of hydroinformatics, the policy and decision-making world is unable to use these highly technical decision support systems (DSSs) because there has been an undue emphasis on the technological aspects. The historical analysis of hydroinformatics concepts and modelling shows that the technical aspects have been incorporated far better than the social aspects. Hence, there have been calls for the development of ‘socio-technical’ DSSs. However, far greater effort is required to incorporate social and political sciences into the domain of DSSs. The goal of this chapter is to elaborate on the illusive interface between science and water policy within the context of DSSs. It is an attempt to address one main question: how to link or find an interface between policy (institutional matters) and science (technical and natural environment aspects). To achieve this goal, a new paradigm for the DSS modelling approach has been envisaged based on combining multiple theoretical and analytical frameworks into a single methodological framework to attain a linkage between science and policy-making. The integrated methodological framework comprises of: (1) two ‘conceptual’ frameworks: (a) decision-making perspectives and (b) IWRM interface frameworks; (2) analytical frameworks: (a) DPSIR socio-technical assessment and (b) institutional analysis (IA) frameworks; (3) core engine of the DSS consisting of coupled decision support tools (DST) such as process, planning and evaluation models; and (4) a stakeholder participation interface framework consisting of (a(a multi-windowed dynamic cyber stakeholder interface (MDCSI) system and (b) DSS performance assessment (uncertainty and risk analysis) tools, within a shell of a graphical user interface (GUI). From experience, it can be concluded that DSSs are not just about software packages but they are a participatory communication platform for an interactive multi-stakeholder decision-making process. The required science-policy interface can be achieved by using a unique analytical approach in which technical, policy and institutional frameworks are combined within a DSS platform with an output framework, the MDCSI system, that facilitate policy dialogue by having a dynamic and interactive policy interface which can be linked to other technical and non-technical systems. DSSs should be integrated with institutional and socio-political frameworks to help attain both financial and institutional sustainability.

Use of Sediments Water in Environmental Monitoring

In this chapter we concentrate on the status of sediment, sources of siltation, sediment Information, also concentrates on the process of setting up monitoring program for the purpose of providing a valid data base for sediment water quality assessments, and modeling. Also the choice of variables to be measured in the water, the sediment in biota and the common procedures for data handling. This chapter concentrates on the existing process of monitoring programmes for interpretation of these data for the purpose of assessing sediment water quality in rivers, and reservoirs, also focus on monitoring strategies requirements for water quality data and interpretative techniques. The choice of the appropriate methods is illustrated by case studies for typical water pollution situations, beside the strategies for sediment water quality assessment. Within the range of water quality issues addressed in this chapter efforts have been concentrated on major areas of vital importance. Monitoring, analysis is done usually as part of the quality control program for drinking water. It concentrates mainly on (Daily, and monthly base) physical parameters mainly suspended sediment and turbidity. While for sediments transport concentration and load, they adopted stations along the Blue Nile and within Al Gezira scheme only, so establishment of National Monitoring Network for sediment monitoring covering all the Nile system highly recommended. Turbidity and suspended solids imposes the major constrains on the development of surface water for domestic use, where silt content exceeds the designed capacity of the treatment plants and their efficiency drop to almost half, and water contamination risk increases. Also due to continuous deforestation, and erosion in the catchments areas, the turbidity of rivers and seasonal streams increase by up to 50% per decade. The sediment creates many difficulties and problems to Sudan, at the same time, it has its negative impact on the Ethiopian Highlands, from where it originates, and degraded the land by erosion and reducing its productivity. Assessment of River Nile and its tributaries, show that the maximum value recorded of suspended solid load in Blue Nile during the flood season approximately 22 kg/m3. The sediment carried annually by the Nile River was averaging 110 million tons as measured in Aswan. However, since the 90s the average increased to about 40 million tons (HRS, 1996), during the last ten years the maximum sediment concentration increased to about 8500 ppm, (45% sand, 15% silt and 40% clay). The Nile water requires careful management to support sustainable development and avoid excessive abstraction, contamination and environmental degradation. To achieve these objectives it needs proper assessment, control and protection in short and long term perspectives. Establishment of adequate monitoring networks can help in solving these problems by implementation of most efficient tools to delimitation of vulnerable zones to siltation and sedimentation. Several models were developed to assess and quantify the impact of land management on water, sediment, nutrients and pesticides at field scale as well as at small watershed scale.

Evolutionary Computation for Single and Multiobjective Water Distribution Systems Optimal Design

Water distribution systems least cost pipe sizing/design is probably the most explored problem in water distribution systems optimization. Attracted numerous studies over the last four decades, two main approaches were employed: decomposition in which an “inner” linear programming problem is solved for a fixed set of flows/heads, while the flows/heads are altered at an “outer” problem using a gradient or a sub-gradient type technique; and the utilization of an evolutionary optimization algorithm (e.g., a genetic algorithm). In reality, however, from a broader perspective the design problem is inherently of a multiobjective nature incorporating competing objectives such as minimizing cost versus maximizing reliability. This chapter reviews some of the literature on single and multiobjective optimal design of water distribution systems and suggests a few future research directions in this area.

On the Relation between Hydrological Forecasts and Water Resources Management

Seasonal streams (wadis) are of vital importance in dry and semidry countries including Sudan. Depending on the rainfall variability of the country, the annual discharge of such wadis was estimated to range from 3 to 7 km3 per annum. In the present study two wadi-discharge prediction methodologies were used to predict the discharge of Khor (wadi) Abu Fargha. The first methodology depends on the El Nino Southern Oscillation (ENSO) event which was divided into six distinct stages. The discharge during each stage was compared to previously estimated rainfall in the dry zone of the Sudan during the concurrent stage. The methodology was found to illustrate about 83% of the discharge behaviour of Khor Abu Fargha. This high prediction skill is attributed to the fact that the wadi is located in an area that is influenced by the ENSO event and to the availability of the discharge data for consecutive 34 years. The use of global sea surface temperatures (SSTs) in rainfall seasonal forecast studies was initiated during the 1990s through the development of empirical-statistical models. Using such methodology the models predicting Abu Fargha discharges were found to excel those for some meteorological stations and the dry zone of the Sudan as well. This is attributed to the fact that wadi discharges represent the whole catchment area whereas rainfall data represent only the rain gauge readings. The models using May global SSTs achieved better predictability in Abu Fargha discharges the thing which was found to be consistent with the results obtained in previous studies by Kassala meteorological station which is located in the vicinity of the wadi. The chapter illustrates the use of the wadi prediction information in forecasting the available storage of the aquifers and concluded that combining the different information, realistic management of surface and ground water resources can be achieved. The study recommended the use of water conservation techniques and integrated dryland management approaches.