Micro watershed characterization and prioritization using Geomatics technology for natural resources management
Author(s)– Binay Kumar, Uday Kumar
Management of watershed encompasses various activities from watershed delineation to monitoring. The suitability of land for development is not only based on a set of physical parameters (geography/terrain, soils, slopes, forest, geology etc.) of the land but also very much on the economic factors. The cumulative effect of these factors determine the degree of suitability and also helps in further categorization of land into different priority orders for development. Sanjai river watershed is located in the central west part of the Subernarekha basin under Kolhan Division of Jharkhand. The study area is totally rain-fed and availability of water for drinking and domestic use is a big problem. The natural recharge process in the area is very poor due to hard compact granite terrain. The response of a watershed to different hydrological processes and its behaviour depends upon various physiographic, hydrogeological and geomorphological parameters. The characterization of a watershed provides an idea about its behaviour. The various parameter characteristics of a watershed behave in more or less perceptible manner. Watershed prioritization is the ranking of different micro-watersheds of a watershed according to the order in which they have to be taken up for development. Holistic integrated planning, involving remote sensing and GIS has been found to be effective in planning for regional development based on watershed approach. Saaty’s analytic hierarchy process is a most widely accepted method for scaling the weights of parameters by constructing a pair wise comparison matrix of parameters where entries indicate the strength with which one element dominates over another vis-à-vis the relative criterion. The pair-wise comparison of parameters results into the “importance matrix” which is based on a scale of importance intensities A Composite Suitability Index (CSI) has been calculated for each composite unit by multiplying weightages with rank of each parameter and summing up the values of all the parameters. Categorization of the CSI is achieved by ranging the CSI into classes, where each range indicates the amount of limitation acceptable for each class.
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Evaluation of Groundwater Potentials in parts of the escarpment areas of southeastern, Nigeria
Author(s) – Okoro E.I, Egboka B.C.E, Anike O.L, Enekwechi E.K
The change in climatic energy balance associated with economic and industrial development has global implications. The groundwater resources of parts of southeastern Nigeria are influenced by the presence of the escarpment and changes in the climatic conditions. The depth to watertable in aquifer in the escarpment area varies between 10 to170m during the rainy season and 80 to 260m in the dry season. The geomorphic characteristics of the escarpment are major controlling factors in groundwater recharge /discharge and availability. Although favourable values of the aquifer parameters of hydraulic conductivity and the transmissivity measured in the area range from 2.08×10-1cm/s to 8.46×10-1cm/s and 150×10-3 m2/hr to 481×10-3m2/hr respectively, variation in watertable and loss of surface water still occur exacerbating water scarcity, public health and food security. The principal flow direction of the surface and groundwater sources in the area is in the NE and NW direction following the influence of the escarpment and consequently creating both surface and subsurface water divide. Nanka Sands and Imo Shale are the major geologic units prevalent in the study area. While huge watertable and confined aquifers are found in Nanka Sands, the Imo Shale forms aquitards except in the sandstone members
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Hydropower opportunities in the water industry
Author(s)- Theophilus Gaius-obaseki
Water and wastewater treatment processes are energy intensive accounting for around 30 to 80 percent of the industry production cost. Given this background, the water companies agree on the need to identify cost effective and sustainable ways of producing energy to reduce its dependence on fossil fuel for energy generation, reduce its carbon emissions, ensure the security of its power supply and offset the increasingly energy cost. Micro-hydropower, a resource that is readily available at the door step of the water companies has been identified as the solution to a sustainable energy option for the industry. Nonetheless, there are no detailed options in the available literature of hydropower application to the water industry. This paper thus gives an overview of hydropower application options available to the water industry (water and wastewater treatment industry.
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