Project Title: Topographic Mapping of Jaldhaka Upazilla under Teesta CAD and Digital Elevation Model Development for flood zoning and land use map for agriculture and urbanization Presented by Shahrior Al Mamun Md. Humayun Karim Bijoy Kumar Ghosh

Survey Features Roads, railways, flood embankments and other drainage divides Alignments Spot height at Intervals not exceeding 300m. Rivers and Drainage Channels Alignments X-Sections at Intervals of m Settlement areas- homestead/town boundaries Bridges, culverts and regulators GPS Location Detail Structural Information type/Dimension/Vents etc) Water bodies, swamps and cultivable areas Spot heights on the land at roughly 100m Interval Roads River Beel Railway

Base Line Survey by RTK-GPS Establishment of Geodetic Values of BMs (Lat, Long, Ell. height) Establishment of Local Datum to BMs (mPWD) Application of World Geoid Model Fly Levelling Survey by Optical Level Development of Local Geoid Model Temporary Control Point (Northing, Easting, RL) Temporary Control Points (Lat, Long, Ell. Height) by RTK-GPS

Concepts of Geodetic Survey H h N Ellipsoid Earth Surface Geoid N = h + H; N = Geoid Height (from Geoid Model) ‘h = ellipsoid height ( GPS) H = Orthometric height

World Geoid Model (WGS-84)

Typical Bench Mark Pillar

Baseline Triangulation Unknown value Unknown Value Known Value RTK Base Line Survey

Data collection by GPS for Line feature

Data collection by Total station

Equipment  Total Station  Leveling Machine Digital Level Optical Level  Digital Echo-sounder 2 nos  Global Positioning System (GPS) Real Time Kinematic GPS ProXR Data Logger Differential GPS Handheld GPS  Communication System Walkei Talkie VHFSafecom

Software  GPS Data Processing GP Survey Path Finder  GIS Geographic Information System PC Arc Info ArcView 3.1 Avenue Programming for (IIS)  General Purpose Microsoft Office97 suit Qbasic Programming

Spot Level at Random Interval

Topographic Map

Digital Elevation Model (DEM)

Flood map