RESTORE THE BALANCE IN THE WATER BALANCE: “The sponge city concept marks a transformative change of China’s water management from the engineering-oriented paradigm to a more holistic and nature-based approach, which aims to strengthen the sustainability of the urban water cycle,” wrote Genevieve Donnellon-May, researcher with the Institute of Water Policy, National University of Singapore (January 2022)

Note to Reader:

The Diplomat is described as the premier international current-affairs magazine for the Asia-Pacific region. Since its launch in 2002, The Diplomat has been dedicated to quality analysis and commentary on events occurring in Asia and around the world. The Diplomat reaches an influential audience of commentators, policymakers and academics with its in-depth treatment of regional issues.

In January 2022, the Diplomat published an article on China’s Sponge Cities, co-authored by Genevieve Donnellon-May and Professor Guangtao Fu. She is a researcher with the Institute of Water Policy (IWP) at the National University of Singapore. He is a professor of water intelligence at the University of Exeter in the United Kingdom.

Are ‘Sponge Cities’ the Answer to Shenzhen’s Water Scarcity?

“Like many other countries, China is facing a multitude of water and water-related challenges, including flooding and droughts, which are linked to climate change. In the past few decades, water-related concerns in China have increased in both intensity and frequency, impacting not only society, but also infrastructure and the environment, resulting in economic losses,” state the authors in their opening paragraph.

Drought Impacts China’s “Tech Hub”

The article’s spotlight is on Shenzhen, a city of 17.5 million residents in southern China. Shenzhen is the fourth most populous city proper in China. The city is often referred to as “China’s tech hub”. Shenzhen is facing its worst drought on record. The authors pose this question, Can authorities find a holistic, long-term solution?

They provide this context: “Sponge cities have been promoted by the central government as a sustainable solution for urban water problems in China. In a sponge city, nature-based solutions are implemented to infiltrate, retain, and store stormwater for future water use. Are sponge cities the solution to prevent droughts and the most severe scenario – “Day Zero” – in Shenzhen?”

Restore the Balance in the Water Balance

The article draws attention to the need to look at all aspects of the water cycle: “The construction of sponge cities aims to prevent flooding from 100-year storm events, but no clear targets for drought management have been put in place. As a result, green measures are purely perceived as an approach for flood risk reduction, without addressing the needs for water demand management and water reuse. To mitigate these concerns, the construction of sponge cities should be configured for wider benefits in drought and flood management.”

To Learn More:

To read the complete article, download a PDF copy of Are ‘Sponge Cities’ the Answer to Shenzhen’s Water Scarcity? 



Adjusting to a Changing Water Cycle in British Columbia: Longer, drier summers & warmer, wetter winters

On the weekend of November 13-14, 2021 the southwest corner of British Columbia was pounded by an epic atmospheric river. Landslides and rampaging rivers severed all highway connections between the Lower Mainland and the Interior of the province.

Barely 48 hours later (on November 17, 2021), the Partnership for Water Sustainability’s Kim Stephens delivered the keynote address at an operator educational event organized by the BC Water & Waste Association (BCWWA). Held in New Westminster, the BCWWA event was distinguished by the fact that it was not a Zoom webinar.

On the contrary, it was the first in-person event for water education in the age of COVID. Thus, it was an ironic twist that Mother Nature prevented speakers and attendees from the Interior from attending. The rippling impact of the natural disaster was further accentuated when some 20 municipal staff from the cities of Abbotsford and Chilliwack were called to duty. It was all hands on deck in those communities after widespread flooding in Sumas Prairie shutdown the Trans Canada Highway.

In summary, the historic storm and flooding was top of mind for all when Kim Stephens, Partnership Executive Director, stepped on stage to provide his career perspective on current events, and put the situation in context.

To Learn More:

Download a copy of the keynote presentation titled Adjusting to Longer and Drier Summers in British Columbia:  Drought Affects Us All.

A Career Perspective on Droughts and Floods in British Columbia

“Dating back to the Halloween 1981 Flood, my engineering career has been defined by an alternating cycle of floods and droughts. This four decade history provides me with perspective that in turn allows me to put current events in context,” stated Kim Stephens.

“In water resource engineering, we often talk about the Hydro-illogical CycleThat means – once a decade you have a flood; once a decade you have a drought. You write a report. You put it on the shelf. A decade later, you have a flood, you have a drought, you update the reports. And so the cycle continues. As the hist0ric storm of November 2021 shows, however, no longer can we postpone action that recognizes the nature and reality of a changing water cycle.”

“Droughts affect all of us, whereas floods affect some of us. That is a fundamental distinction. For this reason, drought history is a good way to tell the story of how our climate is changing. In British Columbia, the mega-drought of 1987 was our first wake-up call. It followed a relatively benign period of some four decades. In rapid succession, we had three droughts in five years. This began to change the conversation in British Columbia.”

“Starting in 2003, we have had one teachable year after another in British Columbia. The pattern has been extremes followed by extremes: droughts, forest fires, wind storms, and floods. Each time the extremes seem to be more extreme. 2015 is a defining year. With hindsight, we can clearly see that is the year when we crossed an invisible threshold into a different hydro-meteorological regime in western North America. We are now in Year Seven of this new reality. Yet only in 2021 is in finally sinking in with the population at large that something has fundamentally changed.”

“As of 2021, we can truly say that the era of weather extremes is upon. And it has happened faster than anyone had projected or expected. Think of the terms that are now part of the everyday vocabulary in weather forecasts on the evening news: heat dome, atmospheric river, cyclone bomb.”

Extremes are More Extreme

“We have always had weather extremes in British Columbia. In my experience, dry months would follow wet months. In other words, the duration of wet and dry periods was comparatively short. On an annual basis, things had a way of balancing out. Now, however, winters are warmer and wetter. And summers are longer and drier. This new reality has huge consequences for water security, sustainability, and resiliency.”

“A generation ago, for example, water supply managers could reasonably anticipate that three months of water storage would be sufficient to maintain supply during a dry summer. Today, however, a 6-month drought is a very real likelihood, and on a repeating basis. In the meantime, populations have also grown in the major centres. From a water supply perspective, think about the implications of a doubling in the need for water storage to make it through a drought.”

“When the water resource is large and water demand is small, variability is not that noticeable. But when the demand (Water OUT) is large relative to the available resource, a variation on the supply side (Water IN) magnifies the perception of impact. In many cases, BC communities have long been operating on narrow margins.”

“When you think about it, the planet Earth is a closed loop system. Mother Nature does not create new water.  The state may change – rain, snow, ice, vapour – but the water cycle is the water cycle. This means that extreme duration dry periods will of course will be followed by extreme duration wet periods. And that has been the pattern since 2015, with 2021 being the most extreme year of all as we have lurched from heat dome to epic atmospheric rivers.”

To Learn More:

Learn From and Build Upon Experience

“A key message is that climate change is not a driver; rather, it is another variable. Climate change is only one factor to consider when we talk about the nature and consequences of extreme weather. The real issues are uncertainty and risk, more specifically how we deal with the first and manage the latter.”

“At the same time, we must recognize that we have so transformed the landscape that there are compounding unintended consequences. These are due to our widespread interference with natural processes. In November 2021, there were numerous factors in play and these combined to magnify the impacts of extreme weather.”

“In particular, the  epic atmospheric river covered such a large area extending into the Interior that it resulted in a previously unimaginable scenario – a major storm coincident with high water levels in the Fraser River late in the year. In the lower Fraser Valley, this meant that inland drainage could not outflow by gravity through the dyke system and into the Fraser River. Normally the Fraser peaks in the late spring and early summer months due to snowmelt, not rainfall.”

“Another key message is that everything is connected. This requires an understanding of how the system works as a whole, rather than focusing on components in isolation of the whole. Thus, a constant challenge for planning is not to prevent past events, but instead is to use past experiences and apply systems thinking to inform and create flexible strategies for the present and the future.”

Blue Ecology is the Pathway to Water Reconciliation

“Michael Blackstock’s Blue Ecology ecological philosophy aligns with the whole-system, water balance approach that the Partnership for Water Sustainability  champions for restoration of hydrologic function and stream system integrity within the built environment.”

“As defined  by Michael, interweaving is about creating a new form of knowledge through collaboration by interweaving useful threads from each way of knowing into a more robust way. Interweaving is not integration, just as equality is not about assimilation and creativity is not empirical. Interweaving is collaborative and incremental rather than a revolutionary process. Collaborators identify packets of knowledge that would benefit from the interweaving process.”

“Blue Ecology is an ecological philosophy, which emerged from interweaving First Nations and Western thought. It is meant to be a companion because it augments existing Western science hydrology rather than displacing this knowledge,” concluded Kim Stephens.