American Journal of Water Resources

by Vieux Boukhaly Traore, Mamadou Bop, Moustapha Faye, Giovani Malomar, El Hadj Oumar Gueye, Hyacinthe Sambou, Abdoulaye Ndiaye Dione, Sidy Fall, Amadou Tahirou Diaw, Joseph Sarr and Aboubaker Chedikh Beye

Original Research

In West Africa, there is serious asymmetry on food safety between consumers and food producers. This made that the management system of food safety in many developing countries became a top priority for authorities and decision makers. In Senegal, the government has selected the flood plain of Kayanga River to develop irrigated agriculture through rice cultivation to promote the food safety. For this, two dams (Niandouba and Confluent) have been built to reinforce water availability .The management of this hydraulic system required the better knowledge of its water resources through the dynamic of the flow. In this paper, we used Hec-ras model to compute the flow characteristics to analyze the hydraulic behavior of this system. The river reach selected, is located between the Niandouba dam and Kounkane threshold. From the DEM of this area, we have divided the river reach into 78 cross sections perpendicular to flow direction and numbered from 1 to 78. Arcgis software is used to extract the bathymetry for each cross section and the distance between two adjacent cross sections. This step allows creating the river geometry with Hec-ras. Four stream flows have successively fixed at Niandouba dam outlet as upstream boundaries. For each stream flow, Hec-ras calculate flow characteristics including: water surface profiles, energy grade line, water surface elevation, flow velocity, flow area, total surface area, volume, wetted perimeter, Froude number, top width, specif force, shear total, power total ,friction loss, head loss, conveyance total, and slope. The high, low and constant flow characteristics areas have been located. The large and narrow section sectors have also been identified allowing estimating floodplain. Certain of these flow characteristics such as the volume, total surface area…decrease from upstream to downstream. Flow velocities are substantially higher in the main channel than in the floodway. This study provides an opportunity for stakeholders to identify important elements of irrigated agriculture for investment plans in this area.

American Journal of Water Resources. 2015, 3(5), 147-154. DOI: 10.12691/ajwr-3-5-2
Pub. Date: November 16, 2015

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Water Balance and Climatic Classification of a Tropical City Delhi - India

by Yashvant Das

Original Research

Water balance is a concept used to understand the availability and the overall state of water resources in a hydrological system which forms the basis of the principle of mass conservation applied to exchanges of water and ensures the magnitudes of the various water exchange processes. Urbanization results in tremendous land cover change dynamics along with subsequent changes in the water and energy balance relationship of earth-atmospheric system. In this paper an attempt has been made to illustrate the small-scale spatial and temporal characteristics of the water balance components and to classify the climate of the tropical city Delhi through the application of the water balance model. In the modeling processes, the potential evapotranspiration (PE) was computed using Thornthwaite’s method and compared with the Penmen’s for the representative station. The complete water balance is evaluated by following an elegant book-keeping procedure given by Thornthwaite. Thornthwaite and Mather’s modified moisture index scheme, which is widely used and accepted by scientific community, is adopted to classify the climate of Delhi. According to the moisture indices, the entire city falls under the semiarid category of climate, except at a location, where it shifted to dry sub humid. This could be a freak occurrence.

American Journal of Water Resources. 2015, 3(5), 124-146. DOI: 10.12691/ajwr-3-5-1
Pub. Date: November 02, 2015

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