Will green cities be a reality in foreseeable future?

The planning, design and implementation of these new developments will either reshape or create new urban landscapes that would have significant implications for natural resources consumption, energy consumption, infrastructure costs, and the socio-economic and ecological resilience of the cities.  Recent evidence reiterates that a city’s livability and its energy demand/use are determined by its physical form, namely the spatial distribution and dimensions of buildings, streets, and parks, as well as the spatial coordination of residences, jobs, social services, and environmental amenities. 

The most energy efficient and livable cities known to demonstrate the following features: 

Built-up areas are compact and the densities of buildings, residents, and jobs are strategically distributed along transportation zones/infrastructure and aligned with social and environmental services and amenities; 

Streets are organised as networks that are dense and interconnected; and  despite their varying lengths and sizes are planned to consider the needs of all users, particularly pedestrians, cyclists and  special users. 

Public transport utilities are designed based on population and job densities, and as the most fundamental consideration are related to stops that are accessible by walking. 

Social and ecological infrastructure including utilities, such as schools, hospitals, parks, and green spaces, are designed to maximize accessibility by walking. 

Urban blocks are small sized and buildings are aligned along streets to create various street fronts and vibrant sidewalks 

Multi-functional (or mixed) uses are ingrained in neighborhoods, blocks, and even individual buildings design and execution. 

Streets are places for people and promote walking; and 

Design and layout of buildings, parks and streets are adapted to local climatic conditions. 

Green spaces are an essential feature of energy efficient and liveable cities. However, policies especially for urban green spaces are based on a predetermined percentage of green space. What really matters though is access and proximity of green spaces with diversified social activities instead of proportion only. A good example that could be worth considering for Chennai is the city of Paris. The spatial distribution of green spaces in Paris results from policies and regulations that have ensured that every citizen lives less than 400 m from a public park, square, or garden. This target has been reached whereas green spaces only represent 5 percent of the urban area. There are a few large parks that allow a wide range of activities for residents, and a large number of very successful pocket parks for daily family activities and intergenerational mix (300 green spaces less than ½ ha). This long tail distribution of parks follows a Pareto distribution, which is an important tool for optimization in economy and urban planning.  In contrast, green spaces in Beijing represent the compliance of 30 percent of the urban area being under green cover. Most of the green spaces are very big parks, and the long tail of small parks is lacking. As a result, residents live more than 3 km away from public parks on average — a scenario that residents of Chennai could relate to very well.   

Greening as an concern that strikes a chord with every resident of a city is a possibility only when he is allowed to experience, contribute and relate to the richness of nature, and accessible parks provide this opportunity.