FUNCTIONAL ASSESSMENT OF URBAN GREEN SPACES- A GIS ANALYSIS Kshama Gupta 1, K P Sharma 1, YVN Krishnamurthy 2, Ram Kolapkar 3

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1 FUNCTIONAL ASSESSMENT OF URBAN GREEN SPACES- A GIS ANALYSIS Kshama Gupta 1, K P Sharma 1, YVN Krishnamurthy 2, Ram Kolapkar 3 1 Scientist, Indian Institute of Remote Sensing, ISRO/DOS, Dehradun 2 Deputy Director, Regional Centers, National Remote Sensing Centre, Hyderabad 3 M. Sc. Student, University of Pune, Pune Abstract: About the Author: The study attempts to assess functionality of public green spaces in four wards of East Delhi district of Delhi NCT, named Krishna nagar, Jagatpuri, Preetvihar and Vishwas nagar. Total area of these wards is Km2 Total population of this region is as per census These four wards were chosen with respect to availability of data and heterogeneous development in these wards. Cartosat-2 and IRS P6 LISS IV merged product was used for carrying out the mapping of urban green spaces, public green spaces and roads in different classes in Arc GIS v Eicher map of Delhi, Google Earth and Field data used for finalize the all layer. For assessment of functionality, buffer and network analysis was carried out in ARC GIS and ground data for various parameters were collected from ground i.e., maintenance, facilities in parks, proximity to heavy traffic road, number of uses, perception of peace, feeling of safety among users, access to public and availability of natural vegetation. Due to time limit, samples parks amongst total public green spaces were selected based on their signature in remote sensing image and distribution. It was found, from GIS analysis in Arc GIS that all parks are maintained only in one ward i.e. Vishwas nagar ward. Authorities responsible for cleanliness of the park should restrict the entry of animals and anti social elements that enhances feeling of safety among users. Mrs Kshama Gupta, M.Tech. ( Urban Planning) Kshama Gupta is a Scientist in Indian Institute of Remote Sensing (Indian Space research Organization) at Dehradun, India. She did M. Tech. in Urban Planning from School of Planning and Architecture, New Delhi, India. Since then she is working as researcher in the field of remote sensing and GIS applications for urban management. E mail ID: Contact No: Most of the sample parks provide more than two facilities as benches and walking tracks. Other than that some parks have playing facilities like swing, slider etc. and those parks are used by people more frequently. 11% samples do not have any kind of facility therefore mostly they are not in use or used by anti social elements. Big parks, such as community and neighborhood parks should provide large number of facilities than small parks. But during field survey it is observed that many big parks do not provide more facilities such as playing facilities, drinking water. Most of the sample parks people are using for dual purpose, i.e. playing and resting. GIS is a powerful tool for analyzing the field data especially for urban studies. An index for assessing the functionality was developed by integrating the GIS analysis and field parameters in ARC GIS. Page 1 of 13

2 1.0 INTRODUCTION 1.1. Urban Green Spaces Urban green spaces are defined as public and private open spaces in urban areas, primarily covered by vegetation, which are directly (e.g. active or passive recreation) or indirectly (e.g. positive influence on the urban environment) available for the users. (Manlun, 2003). Green spaces have their own ecological functionn in the environment. But when we concern with urban environment then we find their social function as well. Urban areas can comprises large variety of green spaces, such as Parks/ gardens & Playgrounds, green space near institution, Industrial area green spaces, P rivate Green spaces. It also includes woodlands, farm lands, etc. Public gardens and play areas provide opportunity for various informal recreation and community events within settlement boundaries. Benefits of UGS Ecological Social Clean Air Adjust Urban Climate Water and Soil Eliminate Noise Recreation Landscape aesthetics Adjust Urban Heat Island Adjust psychology Education Balance between Carbon & Oxygen Absorb toxic gases Trap dust Health Fig 1: Role of Urban Green Spaces in Urban Environment There is very less emphasis in today s development for leaving the open spaces for children s play, a place where one can restore his emotional well being within environment. There is relation between health & nature but little has been translated at the level of planning. Planning here goes by numbers i.e. this much green space for this much population. Or planning may concern with maintenance of Public green spaces to improve the attractiveness of them to enhance the quality of urban environment. 1.2 Functionality of UGS Functionality means a space is fulfilling the function or purpose for which it is designed. Functionality of UGS is complimentary to different functional levels. The distribution of UGS affects their functionality. They must have well distributed for satisfying the social needs of people, such as recreation, resting, playing etc. Well-distributed green spaces can easily access by people and that increases their functional value. Functional levels: Empirical studies assume thatt green spaces fulfill different functions at different levels (Van Herzele et al. 2001). Every level in the hierarchy of UGS system has different function and different levels are complementary to each other. Page 2 of 13

3 For example, large areas of the forest in the urban periphery may have significance to the totality of an urban area for weekend recreation, while small parks in the inner city may have strong connection with the local everyday life. Precondition for use: Distance or walking time from the home is the basic precondition for use of public green spaces. People who live in close proximity to a green space use it frequently, rather than who live further away from green spaces. 2.0 STUDY AREA Four wards within East Delhi district of Delhi (NCT) Latitude: 28º N to 28º N Longitude: 77º E to 77º E Ward Name Krishna-nagar Jagatpuri Preetvihar Vishwas-nagar Table 1: Ward wise area & population distribution of the study area Ward No. Population Area (km²) (2001) DATA USED Table 2: Specifications of various sensors and Data used Data Cartosat II Year 2008 Resolution 1 meter Area East Delhi IRS P6 LISS IV Eicher map Ward map of Delhi Google Earth meters East Delhi :10000 Delhi Delhi meter Delhi 4.0 METHOD 4.1 Thematic Data generation The maps generated by analyzing the remote sensing data are known as the thematic maps. Urban green spaces are digitized and classified with visual interpretation technique, using LISS-IV and Cartosat II merge product in ARC GIS Ver The classes of urban green spaces are as following: Built up, Parks, Roadside green, Railway green, Institutional green, Sports Complex, Playgrounds, Vacant land, Open green, Industrial green and Water body Using selection by attribute query in ARC GIS, parks and playgrounds were separated and exported as new layer named; public green spaces. Assign separate attributes to each type of park and play ground. Using Table 2.5 in Chapter 2 Hierarchy of urban development Standards as per Master plan of Delhi for Urban Green Spaces (MPD-2021), on the basis of area of park we classify the parks and play grounds as public green spaces. This is secondary classification. Page 3 of 13

4 Table 3: Classifications of Public green spaces Totlot Housing area Park and Playground It is the area for children to play. It is located at adjacent or nearby of the house. Area (>125m² to <5000m²) This park / playground is quiet bigger than Totlot. It has walking distance from residents approximately 5 minutes. Area (>5000m² to <10000m²) Neighborhood Park and Playground Neighborhood Parks serve a wide range of recreational needs within the community. Neighborhood parks / playgrounds are larger in size and have many facilities. It has walking distance from residents approximately 10 minutes. Area (>10000m² to <20000m²) Community Park and Playground Area of natural quality, preserving unique landscaping and open space that serves community as well as surroundings. Community parks / playgrounds are much bigger in size and have many facilities. It has walking distance from residents approximately 15 minutes. Area (>20000m² to <250000m²) Then digitization of the road layer has been carried out. Classification of roads in different categories has been done with the help of Eicher map of Delhi. Classify the roads in following classes, Highways, Major Roads, Minor Roads, Local Roads, Railways and Canal. Verify and correct all the classificationss with help of Eicher map of Delhi and Google Earth. 4.2 Network dataset preparation Preparation of the network dataset is very criticall and essential work for network analysis. The network analysis was carried out in ARC GIS from start to end. In attribute table of digitized and classified road layer calculate the length of each type of road. Then add one more field as Minutes that indicates travel time. Put the formula to calculate this field for local roads l*60/2700 and for minor roads length *60/3600 (Here l indicates the length of road and other parameters assume the pedestrian walking speed on local road 0.75 m / second and on minor road it is 1m / second.) For highways and major roads add the field as restriction and put the value 1, because they are not traversable by pedestrian. These road layers are imported into one feature dataset, which is created in personal geodatabase in Arc catalog. Within this feature dataset, create a new network dataset. Within which assign the connectivity to local roads and minor roads at any vertex and for other roads at endpoint. Then assign the global turns and attributes. Run and built the network dataset. Where, highways, major roads, canal and railways are restricted and minor roads and local roads are traversable. 4.3 Buffer analysis Buffer analysis is the vector-based proximity analysis, which is carried out in ARC GIS ver It creates buffer polygons to a specified distance around the Input Features. Used following standards of buffer distance for UGS. Table 4: Buffer distances around each category of park Type of Park Buffer distance (m) Totlot 50 Housing area park 150 Neighborhood park 400 Community park 800 Page 4 of 13

5 Put the buffer distance values in attribute table of Public green spaces layer. Then perform buffer analysis and make the service area polygons. Merge polygons into adjacent polygon and make only one polygon. Intersect this dissolved layer with ward boundary of study area to get the ward wise distribution of service area. Same procedure will follow for each category of park. 4.4Field Survey Field data preparation: Sampling is that part of statistical practice concerned with the selection of a subset of individual observations within a population of individuals intended to yield some knowledge about the population of concern, especially for the purposes of making predictions based on statistical inference. For the field visit we first mark some locations on the study area as a sample points. There are some ground truth points wheree we have confusion with the land feature. We have chosen the samples on the basis of Remote sensing signature, Type of layouts, distribution of samples. Remote sensing signature gives us idea about the land features - Whether it is park or not. In case of some confusion we mark that point as ground truth point. Type of layouts is concern with type of settlements or structure of buildings. Regarding distribution, samples should be well distributed. For Primary survey we have chosen some parameters to check whether the park is operational or not. These parameters are as follows: Field parameters Maintenance of the parks: important parameter is the maintenance if UGS is not maintained, residents cannot use it and that decreases its functionality. Maintenance is concern with Cleanliness, Facilities, like Seating benches, Walking Tracks etc. Facilities: analyze availability of facilities in different categories of park i.e. no facility, walking tracks, benches, drinking water etc. Accessibility, whether park is private or public. If limited to some people only. Safety. By conducting survey we check the feeling of safety in the park, by interaction with people. Sometime children may afraid to go in park due to free animals or anti social elements. Proximity to heavy traffic road, with this parameter we check how nears the park from heavy traffic road. Sometime people may not prefer the park, which is very close to heavy traffic road. Natural vegetation is there or not. If more naturall vegetation is available then children prefer to going in that parks. Peace & quiet. To relax and make the mind fresh people often choose peaceful parks. 5.0 RESULTS 5.1 Ward wise distribution of Total and Public green / Person. it is public then it can be access by any one. But if it is private then access is Calculation of total green per person and public green per person was done using following formulae. Public green / person = Area under Public green / Total population Total green / person = Area under Total green / Total population Page 5 of 13

6 Table 5: Ward wise distribution of Total and Public green / Person. Ward name Population Total green Public green Urban (m²) (m²) Green / Person (m²) Krishna nagar Jagatpuri Preetvihar Vishwasnagar Public Green / Person (m²) Area under green m² Urban and Public green spaces Wards Urban green / Person Public green / Person Fig 2 : Total & Public Green Spaces / Person The graph shows ward wise distribution of total and public green spaces per person. Krishna nagar and Jagatpuri wards have very less green spaces per person than other two wards i.e. less than 5 m2 / person. Although Preet Vihar and Vishwas nagar have more than 20 m2 / person urban green spaces, but they do not have enough public green space per person as per the WHO standards. International minimum standard suggested by World Health Organization (WHO) is a minimum availability of 9 m² public green space per person. Hence, well planning and management should be done for the development of public green spaces by local authority. 5.2 Network Analysis - Calculation of service areas The complete network dataset is shown in next figure. Fig 3: Network Dataset Preparation Page 6 of 13

7 In ArcMap, we use network analysis tool to calculate service area. Add the network dataset. Automatically it will add all the layers with network junction points. Calculate New service area. In table of content Facilities, Barriers, Lines and polygons such fields will appear. Add the parks point layer as facilities. Then go to the service area properties to assign parameters. In analysis setting tab select impedance as minutes and put the value for default break. Here default value can change for different facilities, such as: These break values for time impedance decided on the basis of field observation. Then select the direction as away from the facilities. In polygon generation tab generate polygons and trim the polygon up to 20 meters. Solve and it will automatically calculate the area around facilities with respect to distance and time. It will create service area polygons. Export those polygons into shape file to calculate area. Calculate the areaa for each category of park. Service area in % using Network Analysis Service area (%) Totlot Housing area Neighborhood Community 5 0 Krishna Nagar Jagatpuri Preet Vihar Vishwas Nagar Wards Figure 4 Service area for different category of parks in each ward, using Network analysis 5.3 Buffer Analysis-Calculation of service areas The graph shows ward wise distribution of servicee area under each category of park. In case of Krishna nagar ward there is no housing area park and community park. Thereforee major service area is lying under the neighborhood park. Actually Jagatpuri has no community and neighborhood park. But the neighborhood park, which in Preetvihar cover little service area in Jagatpuri. Preetvihar has less percentage of service area under the category of Community Park than Neighborhood Park. Vishwas nagar shows much realistic picture of distribution of service area. It has well distributed Totlot, Housing Area Park, Neighborhood Park, and Community Park. Therefore service area by buffer increases respectively, i.e. less service area lying under the category of Totlot and more service area lying under the category of Community Park. Page 7 of 13

8 Service area in % using Buffer Analysis Service area (%) Totlot Housing area Neighborhood Community 10 0 Krishna Nagar Jagatpuri Preet Vihar Vishwas Nagar Wards Fig 5 : Service area for different category of parks in each ward, using Buffer analysis Network analysis gives totally different picture of service areas rather than Buffer analysis. The graph shows around 25% area under the service of Neighborhood Park in Krishna nagar ward. In Jagatpuri most of the area served by housing area parks. In Preetvihar most of the area served by neighborhood parks (20%). Vishwasnagar gives almost same pattern like Buffer but the percentage of area is much less than Buffer analysis. Network analysis covered about 20% service area of parks determined by simple buffer analysis. The question may rise as why both the analysis gives different picture regarding service area of parks? The answer is buffer analysis do not consider the accessible roads which are connected from parks to residential areas. Buffer analysis just takes service radius into consideration and makes the service area polygon around the parks. Where network analysis considers the roads, distance from parks, time impedance etc. also it considers restricted roads and canal as barriers. Alll these things are taken into account and then it calculates service area around parks. Therefore it will give more realistic and proper picture. 5.4 Field Information Analysis Maintenance Table 6 Ward wise distribution of maintenance of the samples Ward # of samples Maintain Not maintain % Maintained % Not Maintained Jagatpuri Krishna nagar Preetvihar Vishwas nagar Page 8 of 13

9 Maintained Samples in each Ward % Of Maintenance % Of Maintenance % Maintained % Not Maintained 38% 62% 20 0 Jagatpuri Krishna nagar Preetvihar Vishwasnagar Wards % Maintained % Not Maintained Figure 6: Ward wise maintenance of samples Figure 7: Percentage of Maintenance Above-mentioned graphs show maintenance of the samples. The pie chart gives us overall picture of maintenance of parks amongst samples. In given pie chart we can easily observe almost 60% samples are well maintained and others are not. The bar graph shows maintenance of the samples s in each ward. As we can see in Vishwas nagar ward all the samples are maintained. And in case of other wards differencee between maintained and not maintained samples is almost 50%. Maintenance is concern with cleanliness, well grown plants of flowers, maintained boundary with compound wall, restriction to animals and anti social elements Facilities Table 7 Percentage of types of facilities. Type No Facilities Single Facilities (Benches/ Walking Tracks) Two Facilities (Benches& Walking tracks) More Facilities (Benches, Walking tracks, swing, slider) Benches, Walking tracks, swing, slider, Drinking Water, Toilets # of Facilities % of Facilities % 14% 11% 30% No Facilities Single Facilities (Benches / Walking Tracks) 36% Double Facilities (Benches & Walking tracks) More Facilities (Benches, Walking tracks, swing, slider) Figure 8 Percentages of Facilities Page 9 of 13

10 The Pie chart explains the percentage of facilities available within all samples. Here we can see that most of the samples having two facilities (36%) i.e. benches and walking tracks. Following that single facility is available in 30% of samples. It may contain only Benches or Walking tracks. 11% samples have no facility. Other than this there are more facilities like drinking water, toilets etc. In case of playing facilities swing, slider etc. are available for children. Table 8 Facilities in different categories of parks Types of Parks Facilities Totlot Housing Neighborhood Community No Single Two Multi # of Facilities Available facilities in different Parks Totlot Housing Neighborhood Community Type of Parks No Single Two Multi Figure 9 Available facilities in different categories of park Here we do another type of analysis for facilities available in the different categories of parks. The graph shows that number of two facilities is more than other types of facilities. But in case of Neighborhood and Community parks we can see that number of more than two facilities parks is less, although big parks should have more facilities and multiple uses. Such as swing, slider for children, drinking water, toilets etc. In case of Community park there is one no facility park. While conducting field survey, one big park has been observed; this was not maintained and consists excess natural vegetation. But still people, use it for resting. Due to its large area it is lying under the category of community park Access to people and Use of Park Table 9 % of Accessible parks Access To People # of Parks % of Parks Open to All Limited Table 10 % of use of Parks Use # of Parks % of Parks Single Use >Two Use Multi-Use Page 10 of 13

11 % of Accessilbility % Of Use 20% 14% 29% 80% 57% Open to All Limited Single Use Double Use Multi-Use Figure 10 Percentage of Accessible parks Figure 11 Percentage of use of parks The first pie chart shows that 80% samples are open to all people and others are accessible to limited people. In our sample survey there are some private parks, which are located within area of residential complex. Those parks used by people, which are living in this complex. The second pie chart shows the use of parks. For which purpose people uses it that we observe in the field. Single use means either for playing or resting, double use indicates combination of both. And multi use means Playing, resting and socializing. Where many people can gather for recreation and enjoyment. In chart we can see more than 50% of the samples are lying under the category of double use means they are used by people for resting and by children for playing. Very few parks are used for socializing, because only community parks can provide such opportunity. And in our samples there is lesss number of community parks Feeling of Safety Table 11 Percentage of safe parks Safety Safe Unsafe # Of Parks % Of Parks % of Safety 18% 82% Safe Unsafe Figure 12 Percentage of safe parks Page 11 of 13

12 Given pie chart shows percentage of samples regarding perception of feeling of safety. Around in 80% of samples people feel safe and in other parks they do not feel safe. Earlier we think that there may be relation between feeling of safety and nearness of the park to the heavy traffic road, i.e. if park is near to heavy traffic road children may feel unsafe to reach there. There is no relation between proximity to heavy traffic road and perception of feeling of safety. This case we observee in the field that many parks are near to the heavy traffic road but people do not scared to use the park. While conducting field survey we interact with park visitors and got some idea regarding their perception of feeling of safety. Feeling of safety is concernn with animals and anti social elements. Due to this reason children and ladies may afraid to use the park. And hence park becomes less functional. Conclusion: The study attempts to assess functionality of public green spaces. The whole mapping, analysis and final results all are generated from start to end using ARC GIS ver For that purpose mapping of urban green spaces and public green spaces has been done on the satellite imagery. And find that Cartosat-II and LISS-IV merged product gives better resolution to discriminate built up areas and green spaces. Also it gives sharp boundaries of features; this was helpful to map the boundaries of green spaces, to check the association and to decide the category of green spaces. Remote sensing data is very useful to extract the real world information. On the other hand GIS is useful to analyze the spatial data. Ward wise analysis of urban green spaces and public green spaces gives idea about availability of parks and playgrounds. Percentage of public parks is very less as compare to urban green spaces. Although all wards in study area have less than 9 m 2 / person public green spaces within that Krishna nagar and Jagatpuri wards have less than 2 m 2 / person public green space. This is very much less area than other two wards. As per the World Health Organization (WHO) at least 9 m 2 public green space should be available for a person. Hence, well planning and management should be done for the development of public green spaces by local authority. It was observed that service area around parks using buffer and network analysis generate different values. Calculation of service area around parks using Buffer and Network analysis gives different picture. But the most realistic one is obtained from Network analysis; because it considers pedestrian walk distance, travel time and service area goes along the road therefore it covers much less area than Buffer analysis. Network analysis covered about 20% service area of parks determined by simple buffer analysis. Evaluation of field parameters gives better idea about functionality of public green spaces. Due to time limit we have chosen few samples parks amongst total public green spaces. As Krishna nagar and Jagatpuri wards have very congested roads and unplanned colonies, the availability of the parks is very less compare to other two wards. Regarding maintenance only in Vishwas nagar ward we found our all samples are maintained. Authorities responsible for cleanliness of the park and they restrict the entry of animals and anti social elements that enhances feeling of safety among users. All of the private parks are well maintained than public parks. Most of the sample parks provide more than two facilities as benches and walking tracks. Other than that some parks have playing facilities like swing, slider etc. 11% samples do not have any kind of facility. Big parks, such as community and neighborhood parks should provide large number of facilities than small parks. But the sample survey gives controversial picture i.e. many big parks do not provide playing facilities, drinking water. Even in neighborhood parks percentage of single facility is more than others. Most of the sample parks people using for dual purpose, i.e. playing and resting. For socializing purpose people use only big parks such as community or neighborhood parks. There is relation between nearness of the parks to the heavy traffic road and perception of peace in park. We observed in the field that those parks are situated near by heavy traffic road, having low peace and quiet rather than those parks, which are situated away from the heavy traffic road. But there is no effect of heavy traffic roads on use of the parks by people. As park is not available nearby residential area or the available park may not provide good facilities, people bound to use those parks whichh are located nearby heavy traffic roads. This study also concludes that GIS is a powerful tool to map, assimilate, integrate and doing multivariate analysis. In This study ARC GIS software has been extensively used from start to end for creating database, generating outputs and for various GIS analysis. Page 12 of 13

13 References: 1. Kyushik Oh et al. (2007). Assessing the spatial distribution of urban parks using GIS, Departmentt of urban planning, Hanyang University, Seoul, Republic of Korea. 2. Van Herzele et al. (2002). A monitoring tool for the provision of accessible and attractive urban green spaces, Department Human Ecology, Free University Brussels, Belgium. 3. Dunnett et al. (2002) Improving Urban Parks, Play Areas And Green Spaces, Department of Landscape, University of Sheffield Department for Transport, Local Government and the Regions: London. 4. Manlun, (2003). Suitability Analysis Of Urban Green Space System Based On GIS International Institute for Geo- for different Information Science And Earth Observation Enschede, The Netherlands 5. Miller, (1996). Urban Forestry: planning and managing urban green spaces. New Jersy. 6. Jia J. (2001). Planning and Design of Green Space System. Beijing, Chinese Forestry Press. 7. Comber et al. (2007), Using a GIS based network analysis to determine urban green space accessibility ethnic and religious groups. Departmentt of Geography, University of Leicester, UK. 8. Venn et al. (2004), Ecology in Multi disciplinary study of urban green space: The URGE Project, Boreal Environment Research 9: , Helsinki. 9. Master plan for Delhi, Delhi Development authority, (2007), Hierarchy of Urban Development Standards, MPD Vittaya et al. (2004) Remote sensing and GIS for Urban green space analysis, A case study of Jaipur city, Rajsthan. ITPI Journal 1:2 (2004) Page 13 of 13