Using Green Infrastructure to 'Climate Proof' Our Cities
One of the consequences of our changing climate is an increase in the severity and frequency of storms and other weather-related events in many parts of North America. A 2014 TD Economics report called Natural Catastrophes: A Canadian Economic Perspective estimates that by 2020 the cost of severe weather incidents to Canadians is expected to be about $5 billion, increasing to between $21 billion and $43 billion by 2050. Urban centres, where more than 80 percent of us choose to live, are especially vulnerable. Flood protection standards for most urban and suburban neighborhoods are designed to withstand a one-in-100-year storm. However, severe weather is becoming more common, with storms that used to occur once every 40 years now occurring once every six in some regions of the country.
It's clear that we need to adapt our buildings and urban infrastructure to a new climate reality. The traditional approach has been to build engineered structures such as seawalls, flood channels and containment ponds. However, a groundbreaking study recently released by the Nature Conservancy with support from TD Bank, Urban Coastal Resilience: Valuing Nature's Role, makes a strong case for incorporation of ‘’green infrastructure" in climate resilience measures. The report is based on a case study of the coastal community of Howard Beach, NYC, which was devastated by Hurricane Sandy in 2014. The study's key finding is that a combination of natural (green) and engineered (grey) infrastructure is the most effective means of increasing resilience and could result in avoided losses of up to $244 million from a one-in-100-year storm. The general concept is illustrated in an infographic.
The report supports TD’s position that natural capital considerations should be incorporated into planning decisions. Green infrastructure provides a cost-effective means of climate proofing and also provides a host of environmental and social benefits such as increasing wildlife habitat, absorbing air pollutants, and increasing the livability of our cities.
