Plan well for wellbeing
The fury of Mandakini was nature's response to man-made disaster. It was heart-rendering to see thousands pilgrims being washed away by ravaging river; buildings and roads vanishing in moments. Taking a pause-one wonders, if this could have been avoided. We could have avoided building on flood plains , we could have had control on deforestation and numbers of tourist that visit the fragile ecosystem annually could have been restricted. We have many such disasters in the making, if we do not take actions now. India's urban ecosystem is varied and offers many challenges. However, with improved knowledge on climate science and modeling capabilities, it is possible to predict (with reasonable assumptions) the impacts of climate on development and take corrective actions. Urban Planning in India is traditionally is biased towards economic growth. Land economics and return on investments determine where we build and what we build. While it is critical to look at economic development, it is equally important to consider the environmental and resource impacts of development and suitably build resilience, adaptation and mitigation considerations into city planning processes.
The government of India has several planning instruments to drive the urban development agenda. Cities need to adapt to face future climate shocks and thus resilience building in cities needs mainstreaming. Take the example of Mumbai. Flooded streets and overflowing storm water drains are perennial problems of the financial capital of India. The city grapples with these issues, and yet we have not seen any significant change in development control rules to address the issue. Control on run off from hard paved areas, material choice for hardscaping, adequate open area and green area provisions, integrated plan for sustainable urban drainage and planning for incremental run off can be done in a concerted way to address these issues, in addition to focus on urban management. Singapore is a tropical country with high density development and it rains for significant part of the year. However, the city may have never heard of flooding or has ever witnessed overflowing streets and storm water drains. A closer look at building regulations and development control rules of Singapore, reflect the close connection between their planning instruments and the city's preparedness to address issues such as flooding, temperature rise, two key impacts of changing climate. Singapore's building codes contain performance based prescriptions. The regulations set out prescribed objectives and performance requirement, and building approvals are given once they promise to meet the desired goals. The BCA (Building Construction Authority, Singapore) provides guidance on achieving these goals and compliance is strictly monitored. Singapore has also implemented a green building master-plan and a set of initiatives to realize more and more sustainable constructions. Singapore is not associated with many disasters, though it is impacted by storms, flood & landside. Singapore has design codes for addressing wind loads. Rain, flood loads and landslides are addressed by National Environment Agency, which set norms for drain capacity, minimum platform levels etc.
California, USA has been one of the most progressive states in USA to include environmental sustainability and disaster resilience as part of building regulations and codes. The structural design codes in California address resilience strategies such as effects of snowloads, load of rainwater, wind loads, flood hazards and intrusion of flames and burning embers by wildfire.
In India, the National Building Code addresses the disaster challenge and includes other resilience strategies that a building code should ideally embrace. Adoption of the National Building Code is not a mandate and thus it is not mandatory for the local building codes to embrace NBC and its components. Going back to the issue of Mumbai and increasing flooding situation, it is critical to look at the building regulations. A building in Mumbai is required to keep only a minimum of 15% of area as green area around/within it, which means that upto 85% of ground area can be built. Typically, it is found that developers do not want to leave even an inch of high value space un-built, resulting in dense urban pockets with virtually very less open space, thus having incremental run-off and increased pressure on urban infrastructure. Similarly, urban heat island (UHI) impact is an increasing phenomenon that is resultant of temperature rise due to urbanization.
In a recent study conducted by TERI in the garden city of Bangalore, upto 5oC difference between both day and night temperature has been observed between greener and urbanized areas. UHI has upwardly impact on energy consumption in buildings. Thus pressure on the energy resources is on the rise even in a city that used to boast of moderate climate with minimum requirement for air-conditioning.
Most importantly, increased temperature has immense negative impact on the urban poor, particularly on the ones who toil in outdoor conditions for livelihood. In addition, there is enough evidence to prove that increased temperature is a causative agent for vector borne diseases and non -communicable diseases (heat stroke). As cities face urbanization challenges, it is important to keep track of climate related impacts that may occur. Some suggestion for cities:
The building regulations should evolve with changing city needs and cater to adaptation and mitigation measures.
Imperviousness of urban space is a critical factor that has incremental impact on flooding and heat island. Imperviousness control can be introduced through used of pervious pavement systems, increased open spaces and green areas around building and reduced ground coverage.
Sustainable urban drainage systems in cities, around buildings and in neighborhoods should be promoted.
City level programs on cool roof/green roof can help control UHI impacts
Avoidance of building activities in flood prone areas. Planning instruments and infrastructure planning should account for climate impacts.
It is critical to take help of advanced climate modeling techniques to predict future impacts and redefine urban planning processes and strategies based on such studies. Making cities resilient to future shocks is very important and all our urban planning instruments should factor for climate impacts.