New life for our lost urban rivers!

Kate and Flo knee deep in The Quaggy. Photo: Jon Nicholls (fotologic) via
Kate and Flo knee deep in The Quaggy. Photo: Jon Nicholls (fotologic) via
Cities all over Britain are threaded by 'lost rivers' that have been hidden away in tunnels and culverts. Jenny Jones argues that it's time to restore them to a more natural state - improving habitats for wildlife and people, and reducing flood risk.
The fact that London has 600 kilometres of rivers, with 13 major river catchments areas feeding into the River Thames, is just astonishing.

Even with the arrival of mild Spring weather, the incessant storms and record breaking rainfall are still a vivid memory.

What we should have learnt over the recent months of deluge and destruction is that we are not adapting fast enough to cope with unpredictable and extreme weather events.

The resulting floods have tested and breached the weaknesses in our coastal and river defences causing widespread disruption to thousands of people who have their lives and businesses turned upside down.

Less reported, because less understood, is the devastation for wildlife, natural habitats and fragile ecosystems.

Nature not concrete

Whilst calls for further resources for upgrading concrete flood defences are inevitable, it is time to press the case for equal consideration and far greater resources for more intelligent, back-to-nature long term solutions.

One such approach is river restoration. Not only can it improve flood risk, enhance wildlife habitats and help us to adapt to a changing climate, but by doing so it can also contribute to a better quality of life for its residents.

Schemes such as these should be central to flood adaptation and mitigation programmes.

Restore our lost rivers!

Britain's  'lost rivers' have been built over, encased in concrete, neglected, or remain hidden behind fences and walls.

In urban areas waterways were used for centuries as open drains, but then gradually engineered to allow for housing, road building and preventing local flooding.

This practice spread through into the suburbs through much of the 1900s as cities expanded and became more crowded.

To the uninformed passer-by, who may occasionally glimpse them in an odd place, or has dismissed a river as a mere ditch, the fact that London has 600 kilometres of rivers, with 13 major river catchments areas feeding into the River Thames, is just astonishing.

But unlike rural areas that are often littered with river name signs before road bridges, the same is not true in most urban areas where they remain obscure and lost to society.

However, large sections of these have the potential to provide corridors of green landscape, wildlife habitats and local outdoor recreation spaces, as well as flood defence.

We have an Action Plan

The restoration of London's rivers began in the mid 1980's. Then in 2009, the London Rivers Action Plan was launched. This was an Environment Agency lead programme, in partnership with a wide range of environmental groups, the Mayor of London and other public bodies.

The plan identified a hundred projects with numerous large scale projects on the Lee, Wandle, Ravensbourne, Crane and Roding catchments. Since its launch almost 15km has been restored - a good start, but we still have a long way to go.

The fact that London has 600 kilometres of rivers, with 13 major river catchments areas feeding into the River Thames, is just astonishing.

The projects range from liberating a river from its narrow concrete walls, to restoring the river banks with natural features such as gravel or reed beds. And they are important for many reasons - not just raising environmental quality for people and wildlife, but also to reduce flood risk.

Concrete channels often increase flood risk

Most of the concrete lined river channels were not designed to cope or to accommodate the amount of water that intense rainfall produces - and which is predicted to increase as cliamte change brings more extreme weather.

This is not helped by surface water runoff that has increased as more and more front and back gardens have been covered with impermeable surfaces - like sheds, patios and front garden parking places.

When a heavy downpour happens it can quickly result in surface water, sewer and river flooding, often within minutes; 24,000 London properties at are risk of such flooding.

And of course those concrete channels are good at only one thing - tipping the water downstream as fast as possible - often adding to flood risk.

A success story - Lewisham's River Quaggy

The River Quaggy at Chinbook Meadows in Lewisham was restored along a 500 metre length with a flood storage pond at a cost of £104k.

Another component part of the River Quaggy Flood Alleviation scheme was on a far greater scale. The £3.8 million Sutcliffe Park project in Greenwich involved lowering and reshaping the park to create a flood reservoir with the formerly buried Quaggy re-routed through the middle.

The park now serves as a multi-functional space that is popular with visitors and residents and serves as a combined wetland and river habitat. At times of floods it is capable of storing 85,000 cubic metres of water, protecting local homes and business. After a flood, the water drains back into the river through a 'low flow outlet'.

The vast majority of river restoration projects exist in outer London boroughs where there is the greatest potential to use green spaces, parks, playing field sports grounds as part of river flood plains, whether natural or engineered as part of integrated flood management schemes.

They can both help prevent local flooding, but also by holding back flood waters, they can protect properties farther downstream, avoiding flooding in more central parts of London or areas where the river meets The Thames.

Let's step up our efforts!

At the London Assembly meeting last month I proposed a motion urging the Mayor of London Boris Johnson to prioritise funding and step up river restoration activity along the hundreds of kilometres of rivers and particularly in areas that are at most risk from river flooding. This was agreed by all the political parties.

Separately to this, I also questioned Boris Johnson directly. His enthusiasm for river restoration was clear and for building such infrastructure that is capable of helping us cope with future demands.

There is great potential for stepping up river restoration and I am hopeful that the positive signals will be translated into a major funding and co-ordinating priority for the Mayor.

London government must learn the lessons from last winter's appalling weather and act to protect its residents.



Jenny Jones is a Green Party member of the London Assembly. She sits in the House of Lords as Baroness Jones of Moulsecoomb.

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