How Water Companies And Architects Can Lead The Way On Sponge Cities

Forbes

4 days ago

TOPSHOT - Residents walk on a flooded street in Morocco's Ouarzazate city on September 7, 2024. When ... More powerful thunderstorms hit Morocco's arid south, they brought deadly floods but also provided some relief to farmers as the country grapples with its worst drought in nearly 40 years. (Photo by Abderahim ELBCIR / AFP) (Photo by ABDERAHIM ELBCIR/AFP via Getty Images)
As various parts of the world continue to experience extreme weather events, many authorities must now grapple with how to make cities more climate resilient.
One of the leading climate resilient concepts is the sponge city, where a variety of technological and nature-based solutions can be used to absorb water flooding and future-proof developments.
Urban designers and infrastructure experts are playing a key role in the debate around sponge cities, but other organisations, such as utilities also have a role to play.
Earlier this year, Bentley Systems published a white paper, which highlighted how water companies could take more of a lead to develop plans to reduce surface water flooding and create more sponge cities in the process.
The paper warned the cost of surface water flooding incidents in the U.K. and beyond shows how climate change is impacting towns and cities.
It said it was 'essential' water management plans for towns and cities are integrated, and focus not just on the management of water, but on land and the built environment as well.
Bentley Systems' vice president of infrastructure policy advancement, Mark Coates said it is important for people to know that while floods are the world's most common natural disaster, the largest flood risk people and places face in many developed nations is surface water flooding, in a statement.
Coates added the U.K's Environment Agency now estimates 4.6 million properties are now at risk from surface water flooding in England, around 1.4 million more properties than in 2018.
He said it is a similar situation in the U.S. One analysis shows around 18 million residents live in surface-water related floodplains in the US mainland, which is more than three times the 5.2 million residents living in floodplains caused by rivers and streams.
Adam Boucher, was the operational lead operational lead for Severn Trent Water's £76 million Mansfield sustainable flooding resilience project, which was the largest retrofit profit of its kind in the U.K.
Boucher said the scheme aimed to make the town of Mansfield more resilient to extreme weather events, like flooding, by providing the equivalent of 31 million liters of additional water storage through nature-based solutions.
He added Mansfield was selected for a number of reasons, including issues with surface water not draining away, being in a flood risk area.
Boucher added Mansfield also had the right ground conditions to ensure water could be infiltrated into the soil if properly managed.
As part of the project, Severn Trent developed basins designed to separate surface water from entering the combined sewerage network during heavy rainfall and to capture water by providing additional storage capacity before entering the sewerage network.
Permeable paving was also installed in carparks, walkways, and other hard surfaces to allow water to pass through and soak slowly into the ground beneath.
And small rain gardens on the verges alongside local roads were also installed. These mini gardens use plants and soil to retain and slow the flow of rainwater from surrounding hard surfaces.
'This is the first time a water company has put these interventions directly into a street under its own kind of scheme,' he told me.
'So far, we have increased flood resilience for 96 households, which are now better protected. In addition, a further 128 households assessed to be risk by 2040 have been moved to a lower risk category.'
And Marion Baeli, principal for sustainability and transformation at 10 Design, said other cities like Dubai are also investing in new drainage systems and retrofitting cities with the infrastructure they need to survive extreme weather events, in an interview.
Baeli added while it is difficult to prepare every building and city around the world for the eventuality of an extreme weather event, it is important to carry out risk assessments and put mitigation measures in place.
'The future is going to be quite random, and it's going to be quite extreme,' she told me.
Baeli added planners and decision makers will also have to rethink where the habitable zones in the future will be, as the climate changes.
She said that many seasonal residents in the south of France are now temporarily relocating towards the north during the summer months, as temperatures in the south are regularly reaching 40 degrees Celsius, and on occasion going over 45 degrees.
Baeli added it is also important to educate the architects of the future about resilient design, and how overheating, low energy and decarbonization go hand-in-hand. And
'Climate mitigation and good design are not just for the good of the planet. There is actually a business case you need to consider, so you can carry on benefiting from these buildings and infrastructure in the future when you know the conditions are changing.'