Geo-referencing of Village Maps Project (GVMP) for Maharashtra State

Objectives: 

Digitization and Geo-referencing of Village (Cadastral) Maps for effective utilization of natural resources and socio-economic database for planning, implementation and monitoring / impact assessment of  various development activities.

Description:

Maharashtra state consists of about 44,000 villages spread over 35 districts in the State. The cadastral maps for these villages are prepared and maintained by Land Records Department. The scale of the maps varies from 1:4000 to 1:10,000 and have either no projection or the Cassini projection.  These maps are prepared using chain or plain table survey.  As  these maps are not geo-referenced, hence, they cannot  directly be overlaid on any other resources map prepared using remote sensing data or other methods.

            With the rapid advancement of modern technology, the use of techniques like Remote Sensing, Digital Photogrammetry, Electronic Distance Measuring, Global Positioning System and Total Field Stations would be best suited for creating geo-referenced cadastral database. However, of these the remote sensing based approach was adopted as it is time, labour and cost effective and relatively accurate. The high resolution satellite data, which depicts distinctly the field bunds, roads, tracks, streams, tanks etc. is being used as ground control points database for the cadastral maps geo-referencing. The geo-referenced cadastral maps are then consolidated by mosaicing and merging the outer boundaries of adjacent villages to have a seamless map on taluka, district or any desired administrative unit.

            MRSAC has completed the Geo-referencing of Village Maps Project (GVMP) in respect of all revenue village maps of the Maharashtra State as per the Government Resolution No. MRS-5700/Pra Kra 94/Ka 1415 dated 3rd January, 2001

 

Conventional inputs used for the project: Village cadastral maps in hard copy with survey numbers.

 

Satellite Data used:

The satellite data used for the study are given below:

 

Sr. No.

Satellite

Date of Pass

1.

IRS-1C & 1D PAN Data

1998-99

 
Methodology: 

Tracing and scanning:

            The village maps procured from Land Records Department (LRD) for each tahsil are traced wherever required before scanning in case it is torn, mutilated or not legible.

            The maps are then scanned with the following specifications:

  • Maps are scanned at 200 dpi Black/White mode.
  • The image are stored in Tiff format *.TIF
  • The image orientation is  upright.
  • The image file is  cleaned and de-speckled to remove noise.
  • Feature legibility at 1X (Zoom factor) is  good.
  • Measured length and width within the bounding box is  +0.1% of the map manuscript measurements.

 

Vectorisation / Digitisation:

            The village maps scanned in image format are digitized using heads-up digitisation in CAD environment using  AutoCAD.  A standard  template is used to have uniformity in layers, line type, colors etc.,  for digitisation of the village maps. 

            The default setting in Auto CAD for all the layers is done.  The default settings assume that scanning/paper coordinates are in centimeters.  If the scanning / paper coordinates are in some other units then the symbols, fonts, etc.,  are proportionately scaled.  The symbols, standard legend and logo block for use in the digitisation process are created as symbol libraries and are available both as insert able blocks within the template drawing and also as separate drawings in the "blocks" directory created for the purpose.  All digitisation has been done using standard template designed at MRSAC.  All the features have been  captured on the respective layers as per the template.  After completion of digitisation, symbols have been inserted as per their location on village maps. Text is then inserted for Parcel / Khasara nos.  using  ‘Marathi font'.

 

Geo-referencing:

            Common points are identified on the PAN satellite  image and scanned map where the TICs/GCPs are to be located. The village map is  geo-referenced to the image using sufficient number of GCPs.  The coverage is transformed into the new co-ordinate system, and the projection parameters added to the transformed coverage so as to make it compatible with other spatial database.

 

Edge Matching and Mosaicing:

  1. The IRS-PAN image with spatial resolution of 5.8 m, is displayed in the backdrop        during the edge matching process.
  2. The boundary feature that best fits the image is taken as reference.
  3. The boundary feature that is under lapping  or overlapping on the fitting feature is adjusted using the background image as the reference.
  4. After edge matching, the duplicate boundary is eliminated to keep only one single boundary.       

            After the edge matching process the village maps are mosaiced into one single tahsil cover.  Another coverage containing only the village outer boundaries along with a label of the village code  is created separately by extracting the outer boundaries of villages from the mosaiced cover to form the village map of the districts eventually leading to that of the State.

Beneficiaries: 
  • Land Record Department
  • Agriculture Department
  • Irrigation Department
  • Public Works Department
  • Police Department
  • Forest Department
  • Environment Department
  • Town Planning and Valuation Department
  • Urban Local Bodies
  • Soil and Water Conservation Department
  • Ground Water Survey and Development Department (GSDA)
  • Maharashtra Jivan Pradhikaran (MJP)
  • Various Central and State Research and Academic Institutes
  • Various Non-Government Organisations
Quantum of work: 
440000
villages