Resilient Water Management – How Resilient Cities Share Strategies for Adapting to a Changing Climate

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Water is the lifeblood of a city. Too much is just as dangerous as not enough, and from Cape Town to Byblos, Jakarta to Chennai, climate change demands that any city that wants to survive has to learn to manage and live with water. To be resilient and thriving requires a comprehensive, forward-looking approach to water management that builds on the city’s people, making them a part of the plan and the solution. Water is a significant focus for Resilient Cities Network and our member cities’ efforts to adapt to and mitigate the causes and effects of climate change.

Multi-layered thinking that integrates and supports the community that will live with a piece of new infrastructure, while also mitigating the effects of climate change is the hallmark of a resilient design.

Climate adaptation interventions to address water also present opportunities to achieve resilient outcomes that create lasting, durable systems to help people in meaningful, sustainable ways over the long term. If we are to achieve the boldest ambitions for a better world that we have set as a people, goals like the 2030 Agenda’s commitment to “eradicating poverty in all its forms and dimensions, including extreme poverty, [which] is the greatest global challenge and an indispensable requirement for sustainable development” as we “ensure availability and sustainable management of water and sanitation for all,” cities must approach their work from the perspective of resilience. The breadth of goals, the innovation, consistency, and investment necessary to achieve them, and the threats to their realization, both expected and unexpected, require integrated thinking that views the urban context holisitically, not as a series of disparate human, social, and physical development projects. Cities’ work with water is exactly this, a number of bold steps that bring them closer to a resilient state where these ambitious goals are within reach.

Water played a central role in the emergence of this urban resilience movement, which emerged in the wake of the experiences of New Orleans with Hurricane Katrina and New York City with Hurricane Sandy. From the beginning, cities pursuing urban resilience sought to collaborate and share lessons, which led to collaborations including both New Orleans and New York, as well as Bangkok, Mexico City, Paris, Rome, Rotterdam, Vejle, and many more.

Rotterdam has been a leader in learning to live with water and apply climate adaptation to its planning, with the same spirit that the Dutch have been using to build water resilience, albeit by many other names, for centuries. In the past five years, Rotterdam has made dramatic strides in its capacity to prioritize and develop social resilience in sophisticated ways that build on and integrate with on-ground, built solutions.

Rotterdam’s Water Plazas – One of Their Most Popular Interventions 

Rotterdam sits mostly below sea level, so the city needs to be able to manage flooding. Rotterdam began looking into water plazas over a decade ago, as a way to bring water storage investments above ground, where the public could see their effectiveness, as opposed to more expensive underground tanks that manage rainfall effectively, but invisibly. The city garnered international attention in 2013 and 2014 with the completion of the Benthemplein water square, a perfect demonstration of resilience thinking, although they didn’t call it “resilience” at the time.

The water square idea is deceptively simple. Working with the Dutch urban design group De Urbanisten, they created a sunken community square with three depressed drainage pools that capture floodwater from the surrounding area and gently drain it away. The biggest drainage area is a basketball court surrounded by amphitheater seating. One of the smaller depressions offers a slightly raised area in the middle, perfect for a small performance, while the other has long flat stretches, ideal for kids to ride a skateboard, surrounding a central planter.

Situated in an area with a high risk of flooding, Benthemplein Plaza transformed a drab, foreboding space between some educational and office buildings into a central feature in the community. The plaza invites residents, students, and workers to come together and encourages social connection while bringing some color and greenery to the city. And in the event of extreme rain, the square can collect 1.7 million liters of water from the surrounding area, which is all concrete and paved, lacking any natural drainage. Then it slowly releases the water into a nearby canal and down into the groundwater.

This multi-layered thinking that integrates and supports the community that will live with a piece of new infrastructure, while also mitigating the effects of climate change, is the hallmark of a resilient design. It yields multiple benefits to make the City stronger along multiple axis, benefiting people now and reducing the risk of future shocks and disruptions. And this approach played a central role in the knowledge exchange on water that Rotterdam hosted in 2015, inviting representatives from 15 cities in the network to convene and collaborate in an in-depth, practical learning lab over the course of a few days.

Surat’s History and Future with Water 

Surat’s story is grounded in the Tapi river, which has provided its drinking and irrigation water, been a major source of trade for the port city, contributed hydroelectric energy to the city, and much more. In 2015, the average water supply was 980 million liters per day, which included demand from domestic, industrial, commercial, and institutional consumers. In recent years, Surat’s water supply has become unreliable, with a daily average of only three hours of piped water available to the city. Human activities such as wastewater discharge and unregulated industrial activities, as well sea water encroachment and flooding increasing salinity have worsened water quality.

In addition, seasonal droughts and flooding from rainfall exacerbate these problems, and pose a significant resilience risk for Surat. Situated where the Tapi river meets the Arabian Sea, Surat has a history of flooding. The city experienced five major floods between 1979 and 2015, and Surat loses and average of $30 million a year due to flooding. Larger floods leave as much as 90% of Surat’s population with water in their homes, sometimes lasting several days, meaning 6.4 million people in Surat are exposed to flooding risks, a number that will rise dramatically with the impacts of climate change and a population growth rate of over 4.5%.

Coming out of its resilience strategy process, Surat prioritized water and wastewater management very highly. A relationship between Surat and Rotterdam emerged after attending the 100 Resilient Cities Network Exchange on Water hosted by Rotterdam in 2015 and conversations during the Global Urban Resilience Summit in 2017. Building on this, Surat entered into a formal partnership with the City of Rotterdam, using funding support European Union International Urban Cooperation program and a partnership agenda that was managed by Resilient Cities Network team, to develop more technical and infrastructure-oriented water management strategies. First, the City of Surat sent a delegation to Rotterdam in 2018 to learn about water projects there, including water plazas, multifunctional roofs, and an underground water storage facility. In March of 2019, a Rotterdam delegation visited Surat, where they decided to prioritize improving the quality of drinking water, mitigating water pollution, protecting against flooding, and harvesting rainwater.

Infographic that illustrates examples of resilient water plazas in Rotterdam and Surat, as well as resilient schoolyards as part of cities' climate adaptation response to protect people exposed to flooding risk, either sea level rise or tidal flooding, as well as heat waves.

Surat has piloted two projects based on this input, adapting Rotterdam’s work and experiences to Surat’s context and needs. This first encourages the installation of rainwater harvesting systems onto the rooves of existing government and institutional buildings, and mandates their inclusion in any new high-rise buildings. To date, over 1,350 rainwater harvesting systems have been installed, and the harvested water replenishes groundwater, provides an alternative source of drinking water, and encourages awareness of water conservation.

A render showing the design of a water plaza in Surat that provides an alternative source of drinking water, and encourages awareness of water conservation.

Second, Surat is in the process of creating its own water plaza. The design for the multifunctional public plaza includes open space tailored for community recreational use and ceremonial activities during the Ganesha festival. Of course, it also features an interpretation of Rotterdam’s water catchment technologies, which will capture stormwater monsoons and heavy rainfall, mitigating flooding and preventing pollution-laden runoff from reaching the Tapi River. The water plaza does have precedent in India. The “Kund,” a stepped water tank created by digging a big hole in the ground and lining it with stones and steps, has existed in Indian architecture since at least 500BCE, if not longer, and the Surat team also drew inspiration from this long history.

Surat is currently in design phase of water plaza, and the project architect has published final design for water plaza, which will be able to accommodate 200 million liters of flood and rainwater annually, with a capacity of 2.95 million liters.

From Rotterdam’s Square to Paris Schools, and Back Again 

Paris, France is so dense that nobody lives more than 200 meters from a school. The city has targeted schoolyards with the Oasis Schools program, a multi-pronged climate adaptation intervention that integrates lessons from Rotterdam’s water plazas. The Oasis program consists of creating more shade with green walls and plants, putting planters in the ground and replacing pavement with soil, installing water features, and installing permeable hard surfaces that water can drain through.

This achieves three high-level goals: First, it mitigates the extreme heat Paris has experienced, both contributing to a lessened urban heating effect and protecting schools and students from the extreme heat that walled, cement schoolyards produced – in June of 2018, some schools recorded temperatures of 135 degrees (55 degrees centigrade) outside. Second, it helps Paris address flooding and use rainwater more smartly. The planter and playground design have borrowed from Rotterdam’s water plazas, enabling them to capture flood water, either for reuse in the school, to help cool the school via evaporation, or to drain off into the substrate via special drainable concrete surfaces that can absorb water.

Third, hopefully it increases public access to cooler, green spaces for the general public in a city with the lowest amount of space allocated to greenery in Europe. The program aims to eventually make these green, heat resistant, flood-mitigating space available to the public outside of school hours and during heat waves. This not only serves vulnerable populations, but also brings people and communities together, increasing social cohesion. 

Paris’ Oasis Schools program got a lot of international press and attention, including from Rotterdam. When the Dutch city began looking at how to increase social resilience in a pilot neighborhood called BoTu, a coalition of inhabitants and urbanists directing the program identified a bit opportunity for impact in schools and city squares as public, open spaces. Early in 2020, the BoTu coalition sent a delegation to Paris to visit Oasis School sites and learn about their work.

Example of a resilient schoolyard in Paris that is open to the community, offers greenspace, and has solar panels on the roof, while it protects against heat waves,  and capture and drain off floodwater via permeable ground.

The first round of three schools to benefit from the lessons of this trip are all early in their design process now. Two have designers selected and will begin a participatory design process in 2021, and the third, which features two squares that have been re-designed, will begin construction in 2022. The intention is for all of the designs to leverage the concepts of Paris’ resilience schoolyards that mitigate against heat and flooding, while also integrating into the community to promote community cohesion and serve the needs of inhabitants around the schools.

Scaling Climate Adaptation to Impact Vulnerable People Everywhere 

The story of how Rotterdam’s water plazas have influenced urban resilience design all over the world is very exciting for urban resilience practitioners. City networks are popular because cities want to learn from one another, turning the mistakes and wins of another city into powerful lessons that benefit their inhabitants. The practice of reducing climate change while mitigating its effects on the population is one of cities’ most crucial responsibilities, as well as one of the most valuable opportunities for strong inter-city relationships.

But cities don’t always know about the best ideas being implemented elsewhere, or they lack the ability to identify learning opportunities systematically such that they can bring the ideas home. Resilient Cities Network encourages pilot projects that address the most critical climate change challenges, and then serves as the connector to facilitate these connections, not just between cities but between cities and providers from other sectors. This is exactly what happened between Rotterdam, Surat, and Paris. Given the opportunity to discuss mutual pressing interests, build personal relationships, and share ideas, the cities identified and modified the resilience interventions they needed most, and helped each other along the way.

Under the guidance of the city representatives leading Resilient Cities Network, we will continue to support and foster collaboration and practice exchanges like this, which integrate the needs of urban inhabitants into climate adaptation interventions, to realize multiple benefits and improve the lives and futures of city dwellers.

300M+

global population exposed to flooding risk, either sea-level rise or tidal flooding.

6.4M

people in Surat exposed to flooding risk.

$30M

average annual loss due to flooding.

Resilient Water Management – How Resilient Cities Share Strategies for Adapting to a Changing Climate