London Climate Resilience Review: our key takeaways
The recently-published London Climate Resilience Review, which was commissioned by the Mayor of London, highlights the considerable risks to central London if urgent steps are not taken to improve the city’s resilience to increasingly severe and regular weather events, including flooding and extreme heatwaves.
The independent report warns that multiple climate impacts in London happen concurrently. The 40°C heatwave in July 2022 occurred at the same time as drought and wildfires, and heatwaves are often followed by flash flooding. At that time, when London hit 40°C, there was a 50% increase in water consumption while reservoirs were at their lowest for 30 years and wildfires pushed the London Fire Brigade to its limits.
While the report identifies opportunities for investment in London and growth in key sectors, it warns time is running out.
Notable takeaways from the report include:
The new government’s plans to build more homes and better infrastructure must include updating resilience and technical standards to cope with the weather extremes that London can expect in the coming decades.
London and the whole of the south-east of England needs a new reservoir.
London’s trees, and other green and blue spaces, are under threat from heatwaves, wildfires and windstorms. This weakens London’s resilience because trees reduce street temperatures in heatwaves and decrease flood risk.
Around 43% of London properties are likely to be affected by subsidence by 2030.
The deadline for upgrading flood defences upstream of the Thames Barrier is 2050, and downstream it is 2040; a new Barrier is needed by 2070.
Initial analysis indicates climate change could impact London’s GDP by 2-3% every year by the 2050s, with costs increasing further later in the century.
So what can we do to help?
While many of the reports recommendations are at a city-wide infrastructure level, as Architects working primarily in London, we have a duty to do all we can to ensure our construction projects minimise their impact on the environment.
Given availability of water is a key risk identified, a top priority is to minimise the volume of water a property draws from its supplier. We can do this by recycling grey water, harvesting rainwater and using non-water-based or low-water fire suppression methods.
The increased likelihood of subsidence means this will have to be factored into structural designs moving forwards so they are resilient to the greater movement that results from increases in droughts followed by prolonged heavy rainfall. The generally-popular planting of more trees is also a simple counter-measure to the problem, as is avoiding large expanses of non-permeable paving.
We also need to “de-gas” properties, installing alternative technologies such as air-source and ground-source heat pumps, PV arrays and wind turbines to generate the power needed to heat and cool London’s buildings, both residential and commercial.
LA London take our environmental responsibilities very seriously. The publication of the London Climate Resilience Review serves as a timely reminder to us all of the urgency of the issue, what should be prioritised and measures that can be taken now to start making a real difference.