Surface water run off explained
Run-Off is a term that can be used to describe the water that does not find its way through the road or pavement surface. A certain degree of water will naturally pass through a road surface and so would not have to collect in surface water drainage (swd) systems. The Run-off is thus the water that runs off the road surface into road channels where it should then eventually end up in a surface water drainage system. Run-off is calculated based on the total quantity of water collected in a specified time. If you dropped 1litre of water onto a road surface not all of this water would run-off into surface water drainage systems. The waterproofness of the top layer of the roads pavement structure, known as the surface course will determine what water is permeated through the actually road surface. As we have mentioned a normal road surface has an impermeability factor of 0.8. Therefore if a litre of water were to be dropped onto the road surface 800ml would be run-off and 200ml would permeate through the road surface into the sub soil.
Run-off can be attributed to other situations not just the percentage of water that is seen as run-of from a road surface. For example if you are building a road on or at the bottom of a slope you have to take into consideration the catchment area of water and what run-off will come from this area. Methods of drainage then have to be put into place in order to deal with this. Where slopes contain well-defined water course culverts maybe required to convey water underneath the road construction. Or if the water run-off is not so bad then cut off ditches can be used.
At Burdens we stock an extensive range of products to help you accomidate your surface water run off. Some examples are listed below:
- Aco channel drains
- Gullies
- Gully pots
- Slot drains
- Bridge deck drainage systems
- Kerb inlet drainage systems
- Domestic garage drainage packs
- Permeable paving
- Reinforce grass paving
- For drainage we got the lot!
View our home page to search product range. Or find your nearest Burdens depot via our depot locator. We have a team of experts at each location ready to answer your drainage questions during normal office hours. Or why not use our online enquiry basket to send your local depot your enquiry.
