No one would have thought twice about paving over a garden for a driveway 10 years ago, but with ‘green’ issues now firmly in the public eye, the ecological impact of this practice has come under increasing scrutiny. And it’s not just paving over gardens for driveways that’s attracting attention. With increasingly busy lives being led, householders aren’t finding the time to look after large gardens and are covering them over with patios and other hardstandings that are easier to look after.
Flooding And Quality Of Life
The impact of paving gardens over is to send rainwater straight down into storm drains or sewers. A lawn or garden will soak up the water and hold it up, slowing the water flow down and allowing the sewers system to catch up, particularly in times of heavy rain and flooding.
Having fewer plants around to soak up carbon dioxide and release oxygen obviously makes the environment worse. Another effect on our lives is that hard surfaces soak up heat during the day and release it at night, making the stuffy conditions even worse. Subsidence can be a problem, too. National insurance company Esure has also come out against hard surfaces, saying that they prevent water getting to the soil below, which then dries out and shrinks, in particular with soils that are predominantly clay.
There is also the impact on the animal and plant life to consider. The lack of places for small organisms, insects and the like means less food for small animals and birds.
Action To Be Taken
Taking London alone, studies of aerial surveys by the London Assembly have shown that over 12 square miles of front garden are now paved over. The concerns became so great that the government introduced planning permission requirement for paving over any garden area in England in 2008.
Permeable Surfaces Can Ease The Drainage Problem
So does this mean that it’s all over for drives in our front gardens? Not entirely. Most of the problems outlined above occur with non-permeable surfaces such as Concrete, Tarmac and large interlocked blocks. Careful selection of a permeable top layer will allow water to drain through the surface and get to the ground below.
Some brick pavers that interlock but leave tiny cracks between each one will help with the drainage, as will Gravel. But, in both cases, care needs to be taken over the compacted aggregate that supports the driveway, to make sure water can drain into the surrounding soil.
Providing For Wildlife
The only problem that these products don’t solve is the absence of plants and trees where animal life can prosper. This can be dealt with by laying down hard tracks for each wheel rather than paving the whole garden, which allows you to keep sections of lawn and borders with shrubs and flowers.
Alternatively, there are an increasing number of surfaces that are hard enough to take a car but allow grass to grow through them. Look for grass reinforcement products; they are usually meshes of concrete or plastic that you can lay down over a substrate, then grass can be seeded in the gaps of the mesh.