In a new report, Members of the London Assembly Environment Committee have urged the government to change planning laws to control the number of front gardens being concreted over, saying this is putting pressure on sewerage systems and increasing the risk of flooding.

Gardens play an important role in the capital’s ability to soak up rainfall, yet the report

reveals that London has lost two-thirds of its front gardens, equal to an area 22 times the size of Hyde Park, or the size of 5,200 football pitches.

Rain not absorbed runs into underground drainage systems, putting additional pressure on already creaking Victorian sewerage and drainage tunnels. In recent years, flash floods have meant tonnes of raw sewage have been dumped into the Thames (see related story) killing wildlife and leading in turn to more localised flooding.

Darren Johnson, chair of the Environment Committee said: “There are various reasons why people choose to pave their front gardens – to park their cars, because they think ‘minimalist’ gardens are sophisticated or because they just don’t like gardening. Whatever the reasons, the results are the same. The more paved surfaces there are, the less rainfall is soaked into the ground and the more London’s dilapidated sewerage system struggles to cope. The consequences will be dire unless action is taken to control replacing gardens with vast swathes of concrete.”

The Assembly Members are now calling on the Mayor to launch an awareness campaign on the impact of paving over gardens and to promote environmentally friendly alternatives. Otherwise, the so-called castle could soon start sinking in its own flooded swamp.

By David Hopkins

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