London is the most vulnerable city in western Europe to climate-related impacts including floods and drought, according to a recent report from the Green Party on the London Assembly. Hundreds of schools, hospitals and tube stations in London are at risk of flooding, according to the report.
But if London’s 600km waterway network was enhanced and restored – ie allowed to function more naturally – it could help the city adapt to a myriad of climate and environmental threats coming our way including floods, heatwaves, droughts and poor air quality. ‘There’s the potential for 100km of rivers to be restored in London,’ said David Webb, chair of the London Rivers Restoration Group (LRRG). ‘If these were rewilded, this would have a transformative impact on our city’s resilience to climate change and save money protecting infrastructure and homes.’
This year’s London Rivers Week festival, which celebrates the capital’s many rivers, lakes and streams, brings together river Catchment Partnerships across London to demonstrate actions already underway to showcase what we can do to help protect Londoners, property and wildlife from these threats. In one just one example, the Mayes Brook Park river restoration site in London produced benefits of around £26million in terms of social, tourism, wellbeing and health benefits – a lifetime benefit-to-cost ratio of £7 of benefits for every £1 invested.
‘Restored rivers with green corridors of trees and plants cut flood risk by soaking up flood water. They help regulate the microclimate and cool areas down during heatwaves; and in an era of species extinction, restored rivers can help species survive severe weather and pollution events,’ said Webb.
On one end of the spectrum, urban rewilding can involve large scale re-landscaping and daylighting long-buried rivers. But simple, cheap interventions such as adding woody debris or floating reedbeds can also help our river environments become more naturally resilient.
‘London will face more extreme weather, more frequently. As global temperatures rise we will live with heavier rainfall, and flooding from rivers and surface water. The Mayor’s adaptation programmes need to reflect the dramatic risks climate breakdown poses and as part of this, river restoration needs to play a much more significant role,’ said Caroline Russell, London Assembly Member, City Hall Greens and chair of the GLA Environment Committee.
More than 30km of waterway in London has been rewilded, but progress has slowed and organisers say that there is scope for at least three times this amount of river to be restored, especially if river restoration is included within regeneration and housing development schemes.
Much of London’s river network is hidden or secret, and events during the Week will enable Londoners to find these places, and even walk the path of rivers which are now underground.
‘Engineered river channels block fish from being able to move around and migrate. They’re also not that pleasant or easy for people to find or access,’ said Debbie Leach, CEO of leading waterways charity Thames21 and chair of the Catchment Partnerships in London Group. ‘This means many of us don’t know our local river or how to get to it, but London Rivers Week is helping to change that.’
A Museum of London Secret Rivers exhibition during the Week will shine a light on the story of London’s many secret rivers, while three Secret Rivers Walks will help people trace the path of three buried rivers: the Fleet, the Walbrook and the Effra. Kings College London workshops will showcase how natural flood management and river rewilding schemes are working with rivers catchments to protect humans from climate-related challenges. And a new Fish Migration Map will enable Londoners to help map river barriers many fish face, so that future actions can by-pass or remove those barriers, and help eel, chub, dace, and salmon migrate across the city in the future.
Thames Water provides sponsorship for London Rivers Week. Richard Aylard, Thames Water’s sustainability director, said: ‘Improving the rivers of London is important to protect the environment and enable us to provide a resilient water supply for future generations. We will be carrying out a river restoration project on the River Cray this summer.’