Draft operational guidelines of digital india land records modernization programme (dilrmp) introduction

PART-B: TECHNICAL MANUALS
NLRMP Technical Manual
Chapter-1
Digitization of Cadastral Maps and Integration with RoR Data
Model-I

(Based on the system followed in West Bengal)

The following technical details may be helpful to the digitizing agency or the vendor, if the work is outsourced, in GIS-ready digitization of cadastral maps and their integration with the textual RoR data:

2. Mouza Map: West Bengal has geo-referenced Mouza (a revenue village) maps showing plots (land parcels) in the scale 16” = 1 mile which is equivalent to 1:3960. In densely populated areas such maps are prepared on bigger scales i.e. 32”=1 mile (1:1980) or 64”=1mile (1:990). There are 66,348 such map sheets in A0/A1 size paper covering all the 42042 Mouza of West Bengal, prepared by well established detailed cadastral survey techniques. Each Mouza map contains 1200/1500 plots (property parcel boundaries) on the average surveyed true to scale by Theodolite traverse and chain survey. Later on, the length of each side of the plot and plot area are extracted from the paper map using acre comb. No field dimensions of the individual plots are noted on the map. Each Mouza map has the following features-

1. 
   Sheet heading (Mouza Name & North Direction.)
   
2. 
   Scale of the map
   
3. 
   Plot boundaries with Plot numbers
   
4. 
   Legends
   
5. 
   Conventional signs (Alamats), Bata Plot nos. & Missing Plot nos.
   
6. 
   Contents of the certificate block i.e. contents of the rectangle bearing the signature of the Revenue Officer certifying the contents of the map
   

3. Scope of work for digitization: In order to prepare GIS-ready digitized cadastral Mouza maps, they should be digitized in 3 layers i.e. area layers, line layers and point layers so as to facilitate digital capturing of all the features of the existing paper map. Maps, digitized in this way, provide flexibility required for future corrections. Each plot of land is viewed as a closed polygon and digitized in area layer to provide the area of the plot. A 5 digit number, which is written within the paper map itself, is used for unique identification of the digital polygon. Maps should be scanned to their true scale, vectorized and converted into shape file format consisting of three files i.e. the shape file (*.shp), the index of the shape file (*.shx) and the data associated with the shape file (*.dbf) [item 2 & 3 above], .gif (graphic interchange format) formats [item 1,4, 5 & 6] along with the data in .dbf format [item 5] as detailed in the scope and methodology of the work.