Driveway Drainage – Who cares?
Once upon a time when cars were hard to come by, rain would fall and be soaked up by flower beds in gardens. There was no need for driveway drainage in those halcyon days. The soaked up water would reach the natural underground aquifers. Some of the water soaked up in the ground would evaporate which would provide a cooling affect around the home.
Nowadays, we can’t imagine a life without cars and the majority of houses have a driveway. Depending on the type of driveway surface used, the rainwater will either drain into the road, a flower bed, through the permeable sub base or into a drainage system like a soak away (and then through the sub base.)
A permeable driveway is a driveway where the rainwater drains through the driveway into the ground.
Driveway Drainage – Permeable driveways are:
- Permeable block paving
- Resin bound driveways (if laid on a permeable sub base)
- Gravel driveways
- Grass driveway (using grid system)
- Open-graded tarmacadam
All of these types of driveway surfacing allow water from driveways to drain down and replenish the water tables underground.
Driveway Drainage – Non – Permeable driveways are:
All of these types of driveway surfacing do not allow surface water from driveway to drain down to the water tables underground.
With the installation of pattern imprinted concrete care is needed to assess whether a soakaway is needed, especially if lots of surface water flows towards a house.
A soakaway will connect to channel drainage
Surface water – Driveway drainage
Due to climate change, more rainwater falls each year and flooding has been a direct result of this.
The drains on the roads in most urban areas were built on the basis of average rainfall and (daftly) did not take into account years of paving reducing the capacity of gardens to drain water.
The additional pressure on public drainage systems is why we see more and more localised flooding. In many areas the drains will carry the drain water directly to streams and rivers. So all good right? It would be if it wasn’t for oil, petrol and brake dust to collect on driveways which will then also end up in those rivers and streams. YUK!
If you have drainage problems contact NADC.ORG.UK
In some areas, however, the drainage water will be carried to sewage treatment works. With little rainfall this would be no problem. But with increased rainfall, sewage treatment works can’t cope and an overflow will release the excess water (including raw sewage) straight into natural water sources. This has happened on several occasions over recent years in coastal areas. Look it up, but be warned unpleasant reading!
Driveway drainage – Sustainable Urban Drainage Systems (Suds)
The government put SUDs regulations in place in 2008 and this has limited, or at least partially addressed driveway drainage issues. However, further changes are in the pipeline, so drainage really should be at the top of everybody’s agenda. Do you want a driveway installation that may be non compliant in the future?
It’s welcome that some concrete block manufacturers have evolved with permeable paving products but more has to be done to help customers with permeable sub base installation for these products.