Study of the environmental performance of small urban parks in the densely built areas of Dhaka

Abstract

Urban green spaces are essential element of urban life where climatic conditions are. an important issue for livable urban environment. Ensuring ',i standard green space can be considered ~s an .important part of urban design program. In recent days in many countries, there is a rising concern over rapid urbanization, where high density of population and development works are effecting environment in many ways. The city of Dhaka is such a case where environmental problems are accelerated due to rapid urbanization, high density and scarcity ~of Parks and open space. It is essential _to ensure good quality of life and healthy environment for people in urban areas. In Dhaka the overall situation of urban greenery and Park greenery are in a very poor state. Their distribution is without any meaningful environmental consideration and they are also in a stage of threat and being gradually encroached upon by built areas, without concern about their bel1.efits. Small Parks can have a good social and environmental impact and can be a supplement of large Public Park within the densely built urban area. The ~hesisIS concerned with evaluating the effect of Small Parks on urban environment of densely built areas of urban Dhaka. Accordingly this research intends to explore the environmental influence of Small Parks on the built environments of Dhaka. Theinquity is' done. on 10 Small Parks [less than one acre in size] dist~ibuted throughout the city. In due course of fieldwork, various environmental variables are recorded to evaluate the microclimate of Parks and Park surroundings. Simulation studies were also done, to recheck the environmental performances of the Parks and on their surroundings. Along with this, physical layout of the Parks and various social attributes like activity, use, comfort level etc. also have been investigated to know their social impact. The analysis identifies 'that these Parks has an impact, the intensity of which depends on the. type and quality of its vegetation, its design parameters, connectivity and of ~ourse on surrounding urban morphology. From the analysis and synthesis it is confirmed, that Parks with more canopy trees have maximum impact radius (600ft) and can cool the environment by reducing temperature upto 2.6 deg C and . . .. illuminance 900x lOL, increasing RH 12% and have a good social impact. Cooling range of Parks' with more grass cover is minimum (300ft) and can cool upto 1.6deg C and is not recommended. Therefore a good combination of vegetation (wide canopy trees at periphery, medium canopy trees beside internal walkway and small canopy tree,' sh-rub and gras,s cover elsewhere) are recommended for .better environinentaland 'social performance of"Small Parks and their surroundings. The conclusion recommends on delineating a network of efficient Small Park system at suitable lo~ations to fulfill th~ need of Urban Parks for the city.