The dream: you want to pave your driveway or perhaps, the entire front or back of your property. The problem: you live in an area which is prone to floods and paving over your garden might exacerbate this situation. The solution: porous asphalt.
Porous asphalt is frequently used in parking lots and for other commercial purposes by asphalt paving contractors, but now householders are also waking up to its potential for their homes and gardens.
Porous asphalt is one in an arsenal of solutions to the flooded garden or backyard used by the driveway paving contractor, in their everyday work.
A channel drain can be cut into an asphalt driveway or pavement, to help it move rainwater away from your asphalt surface.
This needs a 2-3 inch trench sinking into the asphalt driveway.
This should be filled with mortar and then covered with a drain cover.
The trench should then have plastic piping that removes rainwater away to a drain or possibly a tank, which can gradually redistribute the water into the ground.
A drainage swale is similar to the drainage drain. The exception is that the swale sends the water down towards a shallow, but wide ditch.
Then, when there is excess rainwater, it will help send the water away from the pavement and into the garden beds, drains and street. It may even send it to an underground well.
Some basic tips on installing a drainage swale in your property are;
Every ten feet, slope around one to two inches, minimum.
The sides should be three to four times wider than the height.
The top eight inches of soil should drain quickly.
If the water goes down too quickly, compost can be added and if it goes too slowly, sand should be instead.
Alternatively, it is possible to lay an asphalt driveway with a 2% gradient on it, so the water runs away from your home or anywhere else where you don’t want it to.
Porous asphalt is a low maintenance option for making your asphalt driveway as floodproof as it is possible for it to be.
The material allows for storm water to run through the asphalt and drain into the surface of the soil beneath. This avoids flooding, puddles and the dangers of having standing water on your asphalt driveway.
And if this is not enough of an advantage, there are more!
Although this is mainly an advantage for commercial construction, there is still an advantage in having a porous surface which can reduce the need for constructing any storm water runoff facilities (like the ones mentioned above).
In other words, it solves the problem of flooding at the root level, rather than tackling the symptoms of it.
Porous asphalt is environmentally friendlier in a number of ways.
It takes less energy in its manufacturing, it reduces smoke and emissions and also removes the need for storm basins and so on.
Another advantage of porous asphalt is that unlike some other surfacing, it will not crack or fall into potholes, to the same degree.
To get the best out of your porous asphalt, it will need regular sweeping and ensuring that any debris is removed from the surface, which may clog its drainage potential.
It is estimated that with proper maintenance, that your porous asphalt driveway could live for two decades or longer. This is longer than most family pets and even, sadly, many marriages, these days!
When you look at it over the entire lifespan of your driveway, porous asphalt is a cost effective choice.
You won’t need to replace it as quickly – with the correct maintenance; and it is less likely to suffer from cracking and other damage.
Living in a flood area shouldn’t stop you from having your dream driveway paved with asphalt!