Preparing for Extremes: Floods Everywhere, Desertification & Water Tech
by China Water Risk 18 August, 2020
Preparing for Extremes: Floods Everywhere, Desertification & Water Tech: This has been a month of extremes. While it has been very wet with floods in many places, it has also been a dry one in others. Desertification is also creeping in. It appears that extremes will define our future – so this month, we look at extreme floods and growing deserts – can water tech rescue us? Read on.
Floods pretty much everywhere. In China’s they rage on – already they have affected 33.85 million people and still, 433 rivers are above danger levels. Meanwhile a third of Bangladesh is underwater with 1.5 million people displaced and over in India, floods are set to continue with monsoon rains expected until September. On the other side of the planet, US is cleaning up after Hurricane Isaias as the UK recovers from flash flooding after a scorching heatwave.
China has long suffered from floods. 7 out of the world’s worst 10 floods have been in China: 5 along the Yangtze river and 2 along the Yellow river. And while floods continue to impact the country, water gurus, Asit Biswas and Cecilia Tortajada, share their views on how China has fared on mitigating and assessing floods. And, if you are wondering if they talk about the Three Gorges Dam, they do.
Despite the advancements in science, the world still faces a major challenge – how to determine the magnitude and duration of extreme floods. One way to predict and analyse floods has been through calculating return periods of extreme floods. But with these events occurring at a faster rate with higher intensity due to climate change, are return periods still useful in planning flood defences? We take a closer look at how they are calculated and why they are still important.
Physical climate risk assessments are also becoming more important. Flood risk assessments is a key component of this, but with increasing flood volatility are they still useful? Not traditional models says Oxford scholar Natalie Chung. With their flawed assumptions and subjectivity, they should only be used as a guide and not a dictating tool. Instead, Chung shares a climate-ready assessment and adaptation model help overcome the uncertainty. See which government is implementing it.
Though this month we are wading our way through floods, we also want to be mindful of the other end of the spectrum, since nothing exists in in isolation. As we work to better manage and adapt for floods, we must do the same for the other extreme, for droughts and desertification. Alarmingly development could speed up desertification, especially in the economic corridors of the Belt and Road Initiative (BRI) as they are already located in arid regions. But there is a way for a greener BRI approach as Dr. Pengfei Li, Dr. Faith Chan and Dr. Juanle Wang point out.
Clearly, we need to better manage water. Can water tech come to the rescue? We turn to BlueTech’s CEO Paul O’Callaghan for answers. O’Callaghan takes us through the successes and failures of the water market over the last decade and gives us the low down on the 2020 water tech market – check out his Top 10 picks for the next ten years.
Floods and droughts are not new, but that these water crises are happening during global pandemic creates even greater challenges. COVID-19 has highlighted shortcomings in water supply and wastewater treatment, stressing our water delivery systems and large centralised plants have proved unwieldy. Instead, Fluence’s CEO, Henry J. Charrabé, shares why we need a decentralised strategy and its many advantages that can help against any future emergency.
It’s urgent because so far water utilities around the world faced multiple struggles – decreased demand of industrial water, surge in demand for residential use, revenue/ subsidy losses to the lack of chemicals for water treatment. If you missed it, hear from the various megacities in UNESCO webinar on COVID-19 & water management (see link in Tapping In).
The good news is in China, the government is on the case, recently releasing an “Implementation Plan for Strengthening Shortcomings for Urban Domestic Wastewater Treatment Facilities” to improve wastewater collection, capacity and drainage and network retrofitting. Investment in water infrastructure is a must as climate change only means a widening of water extremes. We need to find a business model for water in the future that works; a system that leaves over 1.5 million US citizens in water debt is not it.
Basically, we need to prepare for the extremes. Beyond bigger drains to avoid floods, and more reservoirs to withstand droughts, we also need to develop better. With new research pointing to the fact that the worst-case IPCC scenario (RCP8.5) is the best match for current emissions and thus the most useful for quantifying physical climate impacts, we need to multi-task – fast track decarbonisation and adapt for impacts already baked in.
Yes, these floods we are seeing are horrendous – already over 35 million people are affected and new research estimates that USD1.2 trillion of capital stock in Asia are at risk by riverine flooding per year. AND we have haven’t even started to talk about coastal threats such as sea level rise and storm surges. We will cover these next month, but for now, roll up those trouser legs as it will not only be wet but extremely wild.
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