FLOOD RISK MAPPING AND VULNERABILITY MODELING OF GIDAN KWANO VILLAGE, BOSSO LOCAL GOVERNMENT AREA, MINNA, NIGER STATE.

Abstract

Flood management encompasses the holistic and continuous assessment, evaluation and reduction of flood risks. To manage flood in real time format and with high accuracy, it is important to explore both direct and social survey approach. In view of seasonal flooding within Gidan Kwano village resulted to this research. Data were acquired using ’’Hi-Target V30’’ Differential Global Positioning System (DGPS), receivers on Real Time Kinematic (RTK) mode; the acquired data were in Nor things, Easting, and Height (N, E and H) format in order to determine well densified spot heights of points on the ground. Contour map of the area was produced using 0.5 contour interval (C.I), Digital Elevation Model (DEM) of the area was produced to show the raster surface of the area using Surfer 10. Carlson AutoCAD 2010 was used to process the data and stream network was generated to show the direction of flow. Questionnaires were administered within the locally perceived to be prone/vulnerable to flood, to ascertain the nature, degree and consequences/impact of the flood occurrence. The shape file of the structures and other details where overlaid on the spot heights of the area; vulnerability map of the area was produced, together with the shape file of the stream using Arc GIS 10.2 and a buffer zone was determined from the center of the stream after thorough examinations of all the sets of data. Drainage of high standard should be constructed taking the stream course. Those houses within the buffer zone should be demolished and smaller drainage should be constructed within the buildings which are not within the vulnerability zone