Another Drop Lecture Series 2019

Browse the 2019 archive

Thinking Like a Watershed

Tuesday, 26 November 2019, 7:00 PM
Speaker: Dr Chris McLaughlin

This presentation is a reflection on how we think about how the world works. Especially in the context of the restoration of Hamilton Harbour. The title is a play on renowned conservationist Aldo Leopold’s Thinking Like a Mountain, his confessional essay on traditional approaches to how we ‘manage’ the natural world. Ecosystems such as Hamilton Harbour and its rivers and marshes have a built-in capacity for resilience, an antidote to abuse and upheaval. But resilience is undermined by those traditional approaches. Leopold captured the essence of this problem: we too often fail to perceive how systems are connected and how they behave. Learning new approaches is an essential response to the emerging threats of climate and other changes affecting our ability to ‘bring back the Bay.’ This presentation samples similar ideas of original thinkers like Leopold, and suggests how we can meet this challenge by ‘thinking like a watershed.’

Urban-Induced Hydromodification

Tuesday, 8 October 2019, 7:00 PM
Speaker: Dr Dilnesaw Chekol

Urbanization, in general, increases impervious cover in a watershed. When impervious cover is increased, precipitation does not infiltrate as it would naturally. Instead, rainfall is quickly piped and channeled directly to the watercourse. The impacts of increases to impervious cover are evident when comparing stream hydrographs. Rural areas show a gradual response to rainfall, as well as typically having a lower peak flow and extended falling limb. Changes in hydrology as a result of urban development can impact the amount and quality of water reaching a natural feature, as well as the location of different flow paths. Increase in surface runoff from the urbanized areas can result in flooding and erosive damage to our streams and structures such as public and private property. In addition, human activity produces pollution, which in combination with the increased runoff can degrade the quality of our water resources. Practice of managing urban runoff is continuing to evolve as the science of watershed management and understanding of our watersheds grow. Effective management of urban runoff is critical to the continued health of our streams, rivers, lakes, fisheries and terrestrial habitats.

Toronto & Region Conservation Authority (TRCA), as a watershed management agency, develops stormwater management criteria, provides guidance in the planning and design of stormwater management infrastructure for developers, consultants, municipalities, and landowners, and outlines the processes and infrastructure needed to address flooding, water quality, erosion, water balance, and natural heritage. This presentation will discuss about TRCA’s stormwater and floodplain management applied within its nine watersheds.

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Why Almost Everything (Including Progress on Water and Sanitation) is Better Than We Think it is

Tuesday, 10 September 2019, 7:00 PM
Speaker: Dr Colin Mayfield

In an era of seemingly constant bad news and predictions of imminent or future disastrous outcomes for humanity, it is necessary to step back and look at the dramatic improvements in almost everything that have happened during our history. Using United Nations and other sources of data, such a perspective shows immense improvements in the economy, life expectancy, birth rates, population growth, child and maternal deaths, infectious diseases and health, nutrition and food safety, the environment, accidental deaths and general safety and happiness (in many, but not all, countries). After a general survey of these improvements, the state of water and sanitation around the world will be examined.

There are obvious problems still to be dealt with, but a historical perspective gives grounds for a cautious optimism. This pessimism is not new. A 19th century politician summarized it well when he said that “We cannot absolutely prove that those are in error who tell us that society has reached a turning point, that we have seen our best days. But so said all before us, and with just as much apparent reason…….. on what principle is it then, that we see nothing but improvement behind us, we are to expect nothing but deterioration before us?” Thomas Macaulay, (1830) English politician and author (History of England) 1800 to 1859.

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Flash Flood Events, Their Prediction, and the Future

Flash flooding events occur when large amounts of accumulating rainfall exceed the capacity, natural or otherwise, for surface water to be removed. Highly urbanized areas, given their lack of permeable surfaces and constrained drainage, are often most at risk from flash flooding events. Prediction of such events is challenging, particularly when small-scale weather features have an oversized impact – causing thunderstorms to generate copious amounts of accumulating rainfall even when large-scale conditions seem marginally conducive at best. There are also indications that flash flooding events are on the increase across Canada due to anthropogenic climate change.

This lecture will focus on the details of one particular event – the 2013 ‘billion dollar’ flash flood in Toronto – to illustrate the characteristics of a modern, urban flash flooding event and the challenges for weather forecasting. The future of flash flood prediction given new and emerging knowledge and technologies will also be discussed.