Layer Information « Transparent Chennai

LAYER INFORMATION

Flyovers and Special Road Projects

This layer provides information on completed, ongoing and planned flyovers and roads in the city built through special purpose vehicles or public private partnerships. Clicking on any project opens a new window with detailed information about that project, including cost, sources of funding, start date and completion date, agencies and individuals responsible for construction and maintenance of the project, links to information sources and newspaper articles, and more.

Updates: The data was last updated on January 13, 2009. Transparent Chennai aims to update this layer every six months. The next update is scheduled for September, 2010.

Data sources: National Highways Authority of India (NHAI), the Bridges Dept of the Chennai Corporation, the websites of the Tamil Nadu government, Tamil Nadu Road Development Corporation (TNRDC), the Chennai Metropolitan Development Authority (CMDA), especially the second Master Plan for Chennai, and newspaper articles.

Data collection methodology: Members of the Transparent Chennai team visited government offices related to transportation in the city, such as the Chennai Corporation and the National Highways Authority of India and asked for lists of flyovers and large road projects. Team members also searched online archives of newspapers and government websites for more information about each project. All government agencies provided their data voluntarily, and no RtI’s were filed in the collection of this data. Locations of projects were identified on the map using satellite imagery.

Limitations of this data: This data may not be comprehensive because of the way in which large scale transport infrastructure in the city is planned and built. As far as we know, there is no single agency responsible for building roads or flyovers and, as a result, no single source of information about such investments in the city. We do not have any way of confirming that our data is comprehensive.

Our goal: Our eventual goal would be to have a comprehensive database of all investments in road infrastructure in the city to enable citizens to get more information about projects that affect them, to monitor more closely whether government spending has matched action on the ground, and to see whether there have been any geographic disparities in investments in the city. However, even if we had access to this data in a disaggregated form, such a project would require hundreds of points or areas to be geo-referenced (since the government does not generally provide lat/longs, only street addresses in its data), which is currently beyond our capacity.

How you can get involved: If you know of any projects we are currently missing on the site, if you would like to help us collect more data or update this layer, or if you have any suggestions about how this layer can be improved, please contact us.

Census Data by Ward

This layer displays selected demographic information about each ward taken from the Census of India 2001. These ward boundaries are different from the political boundaries given by the Chennai Corporation, which are also available on the site. The layer includes information such as household size, population density and other demographic indicators.

Updates: The layer was last updated on July 24, 2010. It will be updated each time a municipal election takes place, and each time new Census data is released. The next municipal elections in Chennai will take place in 2011 and collection for the 2011 Census is ongoing.

Data Sources: Ward boundaries and ward level demographic data was taken from the Census of India, 2001. Names and contact information for ward councillors were taken from the Chennai Corporation website, and translated from the Tamil by the Transparent Chennai team. The area of each ward used for estimating the population density were calculated using GIS.

Data Collection Methodology: Data for this layer was obtained on the CMDA website, and at the Chennai office of the Census of India. No RTIs were required.

Limitations of this data: There is a discrepancy between the ward boundaries as available on the Census website, and those available on the Chennai Corporation website. We are not sure yet why this discrepancy exists.

How you can get involved: If you have any suggestions for how this layer can be improved, or if you would like to add information to this layer, please contact us.
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Environmentally Sensitive Areas

This layer shows ecologically sensitive areas in the Chennai Metropolitan Area as identified by the Chennai Metropolitan Development Authority (CMDA) in a map titled “Ecologically Sensitive Areas” included in the city’s second Master Plan. Included in this map are areas covered by the Coastal Regulation Zone, marshland, zones for aquifer recharge, reservoirs that supply drinking water for the city, and the catchment area for the Red Hills reservoir.

The layer was created based on the CMDA’s map, which was published in 2007. Unless the CMDA publishes a revision of the map, this layer will not be updated.

Data Source: The layer was taken from the Second Master Plan for Chennai, written by the Chennai Metropolitan Development Authority.

Data Collection Methodology: Since the CMDA does not share shape files (due to security reasons), we used the high resolution pdf available on their site to create a digital layer for our map. Adobe Illustrator was used to isolate layers in the pdf document and do basic cleaning. Then, the map layer was imported into ArcGIS for further cleaning and georeferencing.

Limitations of this data: This layer contains only those areas considered to be environmentally sensitive areas by the government.

Next steps: Our goal is to create a parallel layer of environmentally significant areas as identified by citizens’ groups to compare with this official map.

How you can get involved: If you would like to contribute your time or knowledge to adding to this collection of environmentally sensitive areas in the city, or f you have any concerns about this map, or other suggestions for improvement, please contact us.

Slum Data from TN Slum Clearance Board

This layer includes 242 undeveloped slums within the Chennai Corporation that were identified in a 2003-4 survey, along with legal, demographic, and infrastructure data from the same source. The survey was carried out by Indian Resources Information & Management Technologies Limited (IN-RIMT), Hyderabad, in association with Community Consulting India Private Limited (TCG India), Chennai, on behalf of the Tamil Nadu Slum Clearance Board.

Data Sources: The data here is extracted from annexures to a 2005 report titled “Pre-Feasibiltity Study for Identification of Environmental Infrastructure Requirements in Chennai Metropolitan Area.”

Data collection methodology: Slum locations have been marked based on our interpretation of individual survey maps.

Limitations of this data: We have not verified the information in this layer, and that slum characteristics have surely changed in the years since the survey was carried out.

Next steps: Our goal is to create a comprehensive database of information of the government’s records of slums from past to present, a task which will require georeferencing of hundreds of points currently on paper maps.

How you can get involved: If you have better information about any of these slums, or if you would like to help us create layers of information based on older surveys of the city, please contact us.

Slum Eviction Layer

This map shows slum evictions in the city of Chennai, most of which took place in the last five years. Clicking on each point shows before and after satellite images of the evicted community, its name, the estimated number of huts / households that were evicted, whether these households received compensation money or plots in resettlement colonies, and when the eviction took place.

Updates: The map was most recently updated in August of 2009. Transparent Chennai aims to update the map every year. The next update is scheduled for August of 2010.

Data Sources: The map is populated by information from membership groups of the urban poor who work in Chennai.

Data Collection Methodology: The data was collected by members of the Transparent Chennai team, who visited local group offices, and asked people to identify evictions on a paper map of the city. These locations were then geo-referenced using Google Earth to identify the exact location of the site.

Data limitations: The data has a number of problems. Firstly, it may not be comprehensive, because evictions are not recorded by the government, and no single group is aware of what is happening in every slum cluster. Secondly, because groups are estimating the number of affected people and what sort of compensation they received, these figures may not be exactly accurate.

Next steps: Our goal for this layer would be to create a comprehensive map of evictions in the city that is immediately updated when an eviction occurs.

How you can get involved: If you would like to contribute to the next update of the map, or if you have any concerns or suggestions about this layer, please contact us.

Public Toilets

This layer shows the number of public toilets in each of the 10 zones in Chennai. There is also a detailed map of locations and toilet and user details for 20 toilets in Zone 4. Clicking on any toilet shows you the results of our user, caretaker, and observation survey.

Updates: This layer was most recently updated in September of 2010. The remaining 29 toilets in Zone 4 and the number of toilets in the remaining zones will be added as surveys are completed and RtI applications are returned to us.

Data Sources: Numbers and locations of toilets per zone on this map were obtained from Zonal Offices. Toilets in Zone 4 are currently under the process of being surveyed by members of the Transparent Chennai team, with support from interns.

Data Collection Methodology: Numbers and locations of toilets were initially obtained from visits to Zonal Offices by members of the Transparent Chennai team. These visits were followed up with petitions under the Right to Information Act asking for the same information. The information received through these two sources did not match, but we have selected to use the RtI numbers as the most plausible numbers. Toilets in Zone 4 were mapped by members of the Transparent Chennai team using the addresses given in the list of Zone 4 toilets. Toilet locations were marked using a GPS unit, and surveys for each toilet, including questions for users and for the toilet caretakers were filled out by the team at each toilet visited. The survey was constructed by the Transparent Chennai team.

Data Limitations: Data received from the Corporation’s Zonal offices in person and through the RtI petition does not match. The reasons for this mismatch are not clear, but there appears to be no central register of toilets against which these can be verified.

Next steps: We would like to map all of the toilets in the city, but we are also interested in trying to understand where toilets are needed.

How can you get involved: If you have a creative way of identifying “toilet needs” in the city, please do contact us.

MRTS / Metro

This layer displays the existing and proposed tracks of the MRTS and proposed Metro lines along with the stations marked and named.

Data Source: The MRTS layer was manually drawn and the Metro layer was created from a pdf available on the Chennai Metro website.

Data Collection Methodology: The MRTS layer was manually drawn using Google Maps satellite view using various images available online for reference and for triangulation of station names. The metro map was created from a map available on the Chennai Metro site in pdf format. Adobe Illustrator was used to isolate layers in the pdf document and do basic cleaning. Then, the map layer was imported into ArcGIS for further cleaning and georeferencing.

How you can get involved: If you find any discrepancies in these layers or have ideas of how they could be enhanced do contact us.

Administrative Boundaries

This layer contains various administrative and political boundaries in the city of Chennai, including the current Chennai Metropolitan Area boundary, the Chennai Corporation boundary, the boundary of the planned expansion of Chennai corporation, ward boundaries, zonal boundaries, Assembly Constituencies and Parliamentary Constituencies within the city. The Chennai City Corporation contains 16 different voting constituencies for Tamil Nadu Legislative Assembly seats. The city also includes three different Lok Sabha constituencies. Only the portions of these constituencies contained within the City Corporation are shown on the map.

Updates: This layer was last updated in July 26, 2011 to include the boundary of the Chennai Metropolitan Area. It will be updated again when any changes take place to existing boundaries.

Data Sources: The original Chennai Corporation and ward boundaries were taken from the Chennai Metropolitan Development Authority’s maps in the Second Master Plan for Chennai. The expanded Corporation boundary was taken from this newspaper article and from the Chennai Corporation website. The Parliamentary and Assembly constituency boundaries are derived from the 2008 CMDA Second Master Plan for the Chennai Metropolitan Area, and the Delimitation Commission of India Tamil Nadu Order No. 43, April 2007. The ward boundaries were created manually from pdf files. Adobe Illustrator was used to isolate layers in the pdf document and do basic cleaning. Then, the map layer was imported into ArcGIS for further cleaning and georeferencing. The zone, Parliamentary and Assembly boundaries are derived from these ward boundaries. The Chennai Metropolitan Area boundary was taken from the Chennai Metropolitan Development Authority’s website.

Data limitations: Ward boundaries are redrawn from time to time, and may have changed since 2008. Furthermore, the boundaries shown may not be accurate at the level of individual blocks. Parliamentary and assembly constituency boundaries may also not be accurate at the level of individual blocks. Only the portions of constituencies contained within the Corporation are shown on the map. These will be changed to reflect the expanded Corporation boundaries after the expansion is approved.

Next steps/ improvements: We would like to learn more about the Corporation’s official definitions of ward boundaries, and about the process by which these boundaries are redrawn. Regarding electoral constituencies, some boundaries and constituency names in the Election Commission’s public shapefiles differ from our map, and we would like to understand why this is the case. We would also like to expand this layer to include the entire Chennai metropolitan area.

How to get involved: Please contact us if you identify errors in the map or have more information about these boundaries.

Bus Routes

This layer has a searchable map which contains 50 out of 650 total bus routes in the city of Chennai. The map can be searched by searching for starting and end points, or by clicking on the map on the desired origin and destination.

Updates: There are no scheduled updates to this layer, but we will continue to update the layer as users add information about routes.

Data sources: The list of bus route numbers is taken from the MTC website. Bus routes have been mapped by interns using GPS units as described below.

Data collection methodology: Interns for the Transparent Chennai team were given GPS units and asked to ride the bus from beginning to end and back, marking every bus stop on the unit and checking the name of the stop with the conductor.

Data limitations: Our interns rode the buses at a particular time. The routes will reflect any deviations or errors or changes that were in place at that time. We only have a limited number of routes up on the site now because collecting this data is laborious.

Next steps: We would like to document all the bus routes and bus stops in the city to create a comprehensive searchable bus route database.

How can you get involved: If you’d like to ride the bus with a GPS unit, or input information about new routes, please contact us.

Garbage Infrastructure

The layer shows the locations of official and unofficial dump sites and transfer stations in the CMA. Solid waste management is an obligatory function of the Chennai Corporation. The city has a network or 8 transfer stations and 2 official dumpsites for handling of municipal solid waste. Solid waste from municipalities, town panchayats and village panchayats is handled by the respective local body governments. The layer is important to understand whether the corporation takes into account factors such as distance from neighborhoods, distance from environmentally sensitive areas and water bodies, etc while selecting a landfill site location.

Definitions:

Official dump sites: Sites that are legally owned by the Corporation and used for solid waste management purposes.

Unofficial dump sites: Sites that are not legally owned by the Corporation or not authorized for waste management purposes.

Sanitary Landfills: Dump sites that have provisions for isolation of waste from the environment, therefore making the surrounding area safe from any environmental or health impacts.

Transfer Station: A site that is used for the temporary storage of garbage, before transferring over to the dump site or sanitary landfill.

Note: This map does not provide an exhaustive list of dump sites and transfer stations.

Last Updated: November 2010

Road Safety

This layer features the various infrastructure facilities concerning road safety for all road users like pedestrian subways and foot over bridges, traffic signals and CCTV camera locations. It also features the roads which have high rate of accidents. Under this layer we intend to map the entire road safety infrastructure and the possible threats that cause danger for the pedestrian and other road users.

Updates: This layer was recently updated in May-June 2011. We intend to map the pedestrian crossings, one-ways and even foot paths under this layer and the mapping will be an on-going process along with working with the communities on this issue.

Data sources: We have collected the inventory of pedestrian infrastructure in the city from the corporation of Chennai and The city division of the highway department. We have also collected Traffic and accident related information, pedestrian crossing and one ways from the traffic police.
Apart from this we also have information about the money and the governance structure that looks into the road safety in Chennai.

Data Collection Methodology: The locations and inventory of pedestrian infrastructure was obtained through filing petitions under the Right to Information (RtI) Act, 2005 from the Corporation of Chennai and the city road division of the highway department. The Chennai Traffic Police provided us the information pertaining traffic management and the location of the accidents, and the people affected by these accidents both age and travel mode wise in the city. This was also obtained through RtI and also involved many trips to the additional commissioner (Traffic) Police to understand the process of data collection and the problems they encounter in managing the traffic. We have also gathered information pertaining the finances of road safety in terms of tax and funding which was again sought through RtI.

Data Limitation: Although the data is obtained through the government bodies, the authenticity of it is questionable. While analysing we have found several discrepancies in data which requires further clarification from the various government agencies. As it is obtained under the RtI the data represents the government records which might be outdated. Thus it is necessary to ground truth the data and upgrade the record.

Next Step: Using this data we intend to generate many more maps and work with resident welfare associations and concerned groups in generating more details about the road infrastructure. As the city is due to expand in near future we intend to collect data from the greater Chennai and update our existing records as well.

How you can get involved: If the residents of your area wish to create a road safety and pedestrian friendly neighbourhood, please contact us.

Olcott School Layer

This layer shows you the results of the photo-blog mapping session, which was conducted by Transparent Chennai with the 8th standard students of Olcott Memorial High School. Scrolling over the point shows you what the particular student wrote about the area along with his/her name. Clicking on the point shows you the picture that was taken by the student as well as the original text written in tamil.

Data collection methodology: Places of interest were marked on a google image and cameras were given to two teams, which consisted of 4 students each. With the help of researchers from Transparent Chennai the students photographed these places and wrote small paragraphs of what they thought described that particular area. Later on the teams browsed through the photos they had taken and decided on one photo which they thought best described each location. The points on the maps were then digitized and the photos and original descriptions in tamil were added to these locations by the Transparent Chennai team.

Limitations of this data: The data is meant to be used as a tool to understand how children view their space. However, as the students were unfamiliar with satellite data based navigation, rather than students taking pictures of whatever they liked, points were decided in advance in an effort to familiarize students with common spatial navigation tools like google maps. Due to this, the flexibility to understand how children visualize common spaces is limited to the points that were already predetermined by the team.

Our goal: Our mapping workshop at Olcott School had two goals- the first was to provide students a fun and interactive way to learn the importance of maps, and gain basic skills in cartography. The second was to use the data created (the maps, photos and notes) to understand the the ways in which these children negotiate the spaces that they occupy as it is widely regarded that the views of children are underrepresented in maps.

How you can get involved: If you know of any schools or organizations that would be interested in conducting such a workshop, please contact us.

Police Stations

This layer marks the location of the police stations on the map. The police stations in the city are classified as Chennai City Police Stations and Chennai Suburban Police Stations. There are 27 All woman police stations in the city and 8 in the suburbs. While there are 49 police stations in Suburban areas there are 114 police stations in the city.

Data Sources : The information about the stations was taken from the Chennai Suburban Police and the city police websites. Many of the stations were available on Google Maps and Wikimapia which has been replicated in this layer as well.

Data collection methodology:The data of this layer was compiled through the concerned police department’s website and other help lines. Using the address of the police stations they were located on the map manually and marked.

Limitations of this data: The data was compiled based on the information available on the internet and mapped based on the address provided. There has been no ground truth done for this information and the address may not correspond to its location.

Updates:The layer was last updated on January 27th ,2011. Of the 163 police stations we have not been able to map 55 of which 31 are All-Women police station. The layer will be updated once all the police stations are mapped.

How you can get involved: Please help us map these 55 stations. Contact us to volunteer your assistance.

Water Layer: Chennai Corporation and Planned Expansion

This layer shows current (2011) government water supply and future (2041) water demand for Chennai Corporation and the peri-urban regions that are part of its planned expansion. Click on the administrative area to see details. Future (2041) per capita supply assumes that MetroWater meets projected water demand (MLD) and divides that sum by projected population. MLD: million litres per day; LPCD: litres per capita per day. This layer also shows you whom to contact if you have water questions or problems. Click on the administrative zone for details.

Updates: This information was collected in June/July 2011.

Data sources: (1) Internal MetroWater planning document entitled, “MetroWater Water Supply and Sewerage Schemes in the Expanded City Limit”. MetroWater was unwilling to provide the full document but photocopied several relevant pages. (2) Contact information comes from the MetroWater website, municipality websites, the Rural Development and Panchayat Raj Department website, and filed RTIs.

Data collection methodology: Transparent Chennai visited the offices of MetroWater (CMWSSB), the Chennai Metropolitan Development Authority (CMDA), the Tamil Nadu Water Supply and Drainage Board (TWAD), and the municipalities of Alandur and Valasaravakkam. RTIs were also filed at MetroWater. To verify some of the contact information, sample phone calls were made to MetroWater area engineers.

Limitations of this data: The water supply-demand gap is based on population growth rates that are projections and could change. Moreover, the data for “Future (2041) per capita supply” assumes that MetroWater supply will meet projected demand.

Additionally, some of the data was inconsistent. For example, data source (1) shows that present MetroWater supply in the Corporation is 695 MLD at 90 lpcd. However, data an RTI shows that the same supply is 780 MLD at 150 lpcd. Therefore the water supply-demand gap in the Corporation is also different: data source (1) shows that it is 411.60 MLD and the RTI shows that it is 320 MLD. Interestingly, the public (RTI) document shows more water provision than the private internal document. Also, documents and interviews with municipalities show slight inconsistencies with MetroWater data. For example, Alandur claims that existing water supply is 55 lpcd while data source (1) claims that it is 47 lpcd. Also interestingly, when asked in an RTI, “Does Metro water have information about different water sources and quantities in ULBs outside the Corporation”, the government response was “Metro water has only records about Corporation area only and not the ULBs”. Clearly, according to data source (1), MetroWater does have information about ULBs.

Next steps/ improvements: We would like to understand inequalities in water provision within the Corporation. MLD and LPCD by zonal and ward boundaries would be helpful. MetroWater claims to not collect information by zone. However, calls to several zone Area Engineers showed that this information might be available.

How to get involved: Please contact us if you identify errors in the map or have more information about these boundaries.

Population Growth Rates: Chennai Corporation and Planned Expansion

This layer shows projected annual population growth rates for Chennai Corporation and the peri-urban regions that are part of its planned expansion. Click on the administrative area to see details. The growth rates come from the Chennai City Development Plan (per a Chennai MetroWater document). Updates: This information was collected in June/ July 2011.

Data sources: Internal MetroWater planning document entitled, “MetroWater Water Supply and Sewerage Schemes in the Expanded City Limit”. MetroWater was unwilling to provide the full document but photocopied several relevant pages. They were using the population growth rates from the Chennai City Development Plan to project future water demand in 2041.

Data collection methodology: Transparent Chennai visited and interviewed officials at MetroWater (CMWSSB).

Limitations of this data: While the Metrowater document cites the Chennai CDP as its source for the 2041 population projections, we could not find the same figures from the 2009 CDP itself. In the CDP, the most recent figures found were only for annual growth
rates between 2001-2009 (volume 3, page 7).

Next steps/ improvements: It would be interesting to overlay this map and one of planned city development projects. Are infrastructural and service projects being developed in areas where the city anticipates higher population growth?

How to get involved: Please contact us if you identify errors in the map or have more information about these boundaries.
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