1. Web GIS for Decentralized District Planning : A Case on Cuddalore & Nagapattinam Districts of Tamil Nadu National Informatics Centre, Chennai http://www.tngis.tn.gov.in

2. Introduction :  Geographic Information System (GIS) has become an important tool for managing, analyzing and decision making, by seamlessly combining both spatial and non-spatial data.  In Tamil Nadu, a vast volume of spatial data sets have been generated through GIS projects undertaken by several departments and agencies.  The present challenge is to integrate and coordinate these varied and disparate efforts to build a GIS structure for the state as a whole.  The present project at Cuddalore and Nagapattinam is a first step towards this larger objective of building TNGIS.

3. Basic Issues :  Need for data/information in decision making  Huge volume of existing data sets in various departments are underutilized/unutilized  Sourcewise variation leads to spatial / location inaccuracy of information and mismatch in boundaries  Varied Data formats and its interoperability  Proprietary Vs. Opensource Tools in Managing the Spatial and Non- spatial Information  Data update over time  Capacity Building in District  Integration with the National Spatial Data Infrastructure (NSDI)  Intranet Vs Internet based solutions  Wider dissemination

4. Approach and Methodology :  The major challenge is to integrate and coordinate these varied and disparate efforts to build a GIS structure for the state as a whole.  The present project is a first step towards this larger objective.  To facilitate the district administration to realize the potential of GIS in their day-to-day affairs by providing the base layers on various themes and capacity building for necessary update over time.  Standardized SOI’s District boundary at 1:50 K scale in UTM & WGS 84 projection and datum as the common boundary to be in sync with TN-SSDI as proposed in TNGIS; and later with National Spatial Data Infrastructure (NSDI).

5.  The methodology for establishment of Web GIS at Cuddalore and Nagapattinam district involves the following steps: 1) Collection and Preparation of Spatial and Attribute Datasets for the District from the nodal departments in district and State 2) Generic Database Design and uploading Data for the District 3) Generic Web GIS Interface Development 4) Deploy the web based software along with open source GIS software 5) Training and Handholding

6.  District boundary, as provided by Survey of India at 1:50 K scale in UTM & WGS 84 has been standardized keeping in mind the integration of all spatial layers under State Spatial Data Infrastructure proposed in TNGIS; and later with National Spatial Data Infrastructure (NSDI).  The Spatial and other Non-spatial information (digital and conventional) were collated from varied sources in the government domain and the discrepancies in the boundaries, scale and the co-ordinate systems were removed for establishing the required authentic layers for these districts. For instance, the Revenue and Panchayat Village Boundaries are retained as same for the villages where these boundaries are co-terminus. Further, the required bifurcation, merging of boundaries is carried-out for necessary revenue/panchayat village boundaries. Collection of Spatial and Attribute Datasets for the District

7. (Contd.)  Spatial layers for Cuddalore and Nagai have been collected from the nodal departments such as : 1. Agriculture Engineering Department 2. Tamil Nadu Water And Drainage Board 3. Institute of Remote Sensing, Anna University 4. Bharathidasan University 5. Institute of Water Studies, PWD 6. Ground Water, PWD 7. NIC / National Spatial Database  The sources of major attribute datasets are : 1) Population Data (PCA) of Census 2001, DCO 2) Agriculture Department 3) Health Institutions Data - DPH 4) RD Panchayat Villagewise Infrastructure Data – DRD 5) Below Poverty Line Data (BPL) – DRD 6) Educational Institutions Data 7) Rainfall Data – AD, Statistics

8.  Necessary linking of these spatial layers with the major attribute data sets from the respective departments is carried out, so that the regular update of these data sets can be done without much effort. For instance, the following major data bases are linked; G-Return Agriculture Data Rural Infrastructure Data Census 2001 - Primary Census Abstract Data Census 2001 - Village Amenities Data 7th All India Education Survey Data PHC, HSC, Hospital Data from Public Health Department  In addition to the above, various spatial layers like location of fire-stations, police stations etc. are also provided with a scope to add the necessary attribute data sets.  Further, major efforts on building necessary spatial layers on various natural resources like soil, water resources, delineation of watershed, location of tanks, etc are also provided. Collection of Spatial and Attribute Datasets for the District (Contd.)

9.  PostgreSQL – an ORDBMS as the Backend Database and PostGIS is an extension of PostgreSQL to support the storage of Spatial Datasets.  The database has been designed to store the spatial or map data, the attribute information with “Master Tables” to store the metadata – data on spatial and attribute datasets. Master tables act as a directory.  The design has been made in such a way that any layer would be dynamically linked to any kind of attribute dataset. For querying and thematic mapping this gives more scope to add / link any kind of attribute information in future also.  The database related activities comprise of - The corrected/reprojected Spatial Layers (more than 80 layers) in the form of ESRI Shape File format have been imported into PostgreSQL / PostGIS database.  Metadata on these layers/attribute datasets have been fed into respective master tables to enable queries in different styles / kinds of mapping etc. Generic Database Design and uploading Data

10.  Web GIS has been adopted as the technology to provide interface for the various datasets keeping in mind the large number of users  UMN MapServer is used as the Open Source Web GIS Server with PHP/MapScript as the scripting environment. This would enable us to host the data on any platform.  The following software modules have been currently created: Dynamic thematic or choropleth mapping that supports following classifications over web: Equal Interval Equal Count (Including zeros values). Equal Count (Excluding zeros values) Custom classification  Based on the metadata fed on the numeric attribute datasets, the software decides the mapping layer which includes: Revenue villages, Panchayat villages, Taluks and Blocks Generic WebGIS Interface Development

11.  Simple Query module to enable query on the attribute datasets and Complex Spatial or Administrative queries to query on GIS and attribute datasets.  Alphanumeric based dynamic thematic/unique symbol map creation module to enable mapping on spatial layers like Soil, Geomorphology, etc. based on an attribute stored in the layer itself.  Search – Spatial Search on Administrative Units  Authentication to check the user credentials before showing maps  Master Entry pages to enable entry into important master tables / metadata  Update of attribute datasets through Excel sheets or any other RDBMS is available for administrators Generic WebGIS Interface Development (Contd.)

12.  The Web based software has been deployed on the Server at Cuddalore and Nagapattinam  Quantum GIS open source GIS software has been installed on Clients  Sensitization of the GIS program has been done at the district level  Key departments have been identified and nodal persons nominated for taking the project forward by the respective District Collector. Deploy the web based software along with open source GIS software

13. Design Architecture : Spatial DataNon-Spatial Data SQL Server MS Access ESRI SHP PostgreSQL/ PostGIS PostgreSQL Web Server (Apache / IIS) Web DesignStyle SheetsLayoutsNavigational Sequence Open Layers JavaScript MapServer API/CGI PHP Remote User

14. Interaction among the Components : PostgreSQL Database Generate map images Stor es Geo spat ial and busi nes s dat a Web Browser Web Server PHP/Map Script Map Server PostGI S PHP Scripts create the map object and access the database Defin e PHP class es for GIS object s Provides function to manage geospatial data

15. Spatial Table Name Spatial Column to link Non Spatial Table Name Non Spatial Column to link Census Codes ……………. …………..... Census Codes ……………. …………..... Census Table Meta dataTaluk Layer Metadata Design

16. Training and Handholding  Initial sensitization with the user departments in the districts is done through a consultation process under the Chairmanship of District Collector.  The necessary training programme organized at Cuddalore and Nagapattinam in coordination with SPC and district administration for the key personnel's in various district departments  Necessary guidance to sustain the efforts made is being provided for additional requirements over time.  Handholding support at the District is also extended for some period to stabilize the system and ensure its sustenance.

17.  The spatial queries / administrative queries will provide a good Decision Support System for the administrators. Since the queries can be directly made on the spatial datasets in an RDBMS environment, the results will ensure only the up-to-date output. Any change in the layer would reflect immediately on the result sets.  The application provide means for importing attribute datasets even from an Excel sheet and update the datasets periodically so that maps would reflect the latest information. In addition, one can also import datasets from other databases like SQL Server / MS Access etc.  The administrator has the complete control of the application through which he / she may add more parameters for thematic mapping / querying, etc by altering the metadata through the forms provided for this purpose.  The district environment does not restrict users with only the web based interface. Provision of Quantum GIS – a full fledged Open Source GIS software ensures a full functionality GIS tool for the authenticated users in various departments to leverage the full potential of the GIS prepared for the district.Achievements:

18. Achievements(contd.):  Without any fresh digitization of maps and by collecting the spatial layers from different agencies, more than 80 layers of data have been brought under SOI’s common district boundary. Bringing these layers within one common boundary itself had been a major task accomplished in this project.  The deployment proposed is modeled on open source software mentioned below. This will enable easy replication at minimum cost for the Software tools for promoting GIS in Decentralized Planning and development in district. Server OS : Suse Enterprise Linux 10 Database : PostgreSQL / PostGIS for Attribute and Spatial datasets GIS Server : UMN MapServer with Open Layers for AJAX based map rendering Scripting : PHP with PHP/MapScript wrapper for MapServer Client OS : Suse Desktop Linux 10 GIS Software : Quantum GIS with PostgreSQL / PostGIS Support

19.  Through State SDI initiatives (TNGIS) for the State, all the layers prepared have been collated from different departments in digital vector formats to avoid re-digitization activities. This could be possible only through the SPC’s active involvement in identifying and collecting the datasets from different the nodal departments.  The generic database model created will enable faster replication of the GIS application to other districts and easy integration with attribute datasets later by the District GIS Administrator.  Web based application interface ensures wider scope for the project and the number of users who can access the system. The user needs only internet connection and a browser to access the system.  Almost all the above maps are customizable for size, colour, fill style, titles, etc. so that the user is provided with a more flexible map making interface.  The application also provides a PDF output which can be used for presentations / reports, etc. Achievements(contd.):

20. 20 Water bodies in Cuddalore district with Overview window, Info Window, Legend Window

21. TN SPC & NIC, TNSC SKOCH SUMMIT 2009 Spatial / Administrative Queries

22. 22 Administrative queries Villages with more than 6000 population but without any Health facility

23. Dynamic Buffer Map around National Highways

24. 24 Villages from where people have to walk at least 1.5 km to access a health facility Administrative queries

25. Simple Thematic Maps - Theme on Total Population

26. Attribute Query and Map Output – Total Literates less than 3000

27. Dynamic Unique Symbol Map Generator

28. GPS Schools – Source – School GIS (BDU)

29. Search – Chidambaram Taluk

30. Overlay Layers Dynamically – Apply fill styles / colours / size, etc.

31. Overlay layers – Taluk boundaries and Railway Lines

32. Layer Category wise List of Layers

33. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 1 District Bounday of Cuddalore 2 Revenue Divisions of Cuddalore District 3 Taluks of Cuddalore District 4 Blocks of Cuddalore District 5 Firka of Cuddalore District 6 Assembly Constituency in Cuddalore District 7 Parliamentary Constituency in Cuddalore District 8 Chidambaram Parliamentary Constituency in Cuddalore District 9 Cuddalore Parliamentary Constituency in Cuddalore District 10 Revenue Villages of Cuddalore District

34. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 11 Panchayat Villages of Cuddalore District 12 Urban Areas of Cuddalore District 13 District Capital Location of Cuddalore 14 Revenue Divisions Locations of Cuddalore District 15 Taluks Capitals of Cuddalore District 16 Blocks Capitals of Cuddalore District 17 Firka Locations of Cuddalore District 18 MLA's Office Locations in Cuddalore District 19 MP's Office Locations in Cuddalore District 20 Urban Areas Locations of Cuddalore District

35. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 21 Land Use 22Habitations 23 District Roads 24 NH Roads 25 Railway Lines 26 Water Bodies 27Drainage 28Settlements 29Forest 30Canal

36. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 31Wells 32Watersheds 33 Sub Watersheds 34 Mini Watersheds 35 Micro Watersheds 36Structure 37Wasteland 38Wetland 39Soil 40Lithology

37. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 41Geomorphology 42Agriculture 43Wasteland 44Rivers 45 SROs in Cuddalore 46 BSNL Exchanges Covered 47 Raingague Stations in Cuddalore 48 PHC's in Cuddalore 49 HSC's in Cuddalore 50 MLA's in Cuddalore 51 Main Locations in Cuddalore

38. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names Vellar River Basin Layers 52 Vellar River Basin Boundary 53Settlement 54Hill 55Hill1 56Control_well 57FinalControl_well 58NewControl_well 59Tank 60Sub_basin_boundary_final

39. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 61Stream 62 River (Line) 63Reservoirs 64 Rivers (Polygon) 65Canal 66Anaicut 67 Land Use

40. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names Drainage 67Tank 68 Sub Basin Boundary 69Stream 70 River Line 71Reservoir 72 River (Polygon) 73Canal 74Anaicut

41. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names Ponnaiyar River Basin Layers 75 Ponnaiyar River Basin Boundary 76 Control Wells 77HP&U 78Anaicut 79Reservoir 80Canal

42. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names 81 I Order Streams 82 II Order Streams 83 III Order Streams 84Rivers 85Structure 86Tanks 87Geology 88Geomorphology 89 Ground Water Potential 90 Land Use 91Intersections 92Lineaments

43. List of layers prepared under this common District Boundary Cuddalore District Layers’ Details No Layer Names Paravanar River Basin Layers 93 Paravanar River Basin Boundary Other Layers 94 Police Stations 95 Accident Prone Areas 96 EB Substations