When it comes to road surfacing, you might think that choosing the right materials (tarmac, asphalt, bitumen) and craftsmanship are what matter most. But without proper drainage in road surfacing, even the highest quality surfacing can fail prematurely. Surface water may seem like a small issue—but over time it causes cracks, potholes, washouts, and structural weakening. For contractors, local councils, or property managers, understanding and implementing good drainage solutions is key to ensuring durability, safety and reducing long-term maintenance costs.
In this post, we’ll explore how drainage works, what design factors to consider, best practices/tips, and how companies like Total Surfacing Solutions approach surfacing drainage to deliver reliable, long-lasting roadways.
What happens when drainage is poor
Poor drainage in road surfacing can lead to:
- Water pooling / ponding on the road surface, adding weight and causing slipperiness and decreased safety in wet conditions.
- Subsurface damage: Water infiltrates into the base layers, softening them and causing movement, subsidence, or deformation under load.
- Freeze-thaw damage (in cold climates): Water trapped in pavement cracks freezes, expands, then thaws, weakening the pavement over repeated cycles.
- Accelerated wear: Water carries away fines, reduces bonding between layers, causes rutting, cracking and potholes.
- Erosion of edges and shoulders, undermining the integrity of the whole road or pavement.
Key design considerations for effective drainage
To ensure road surfacing projects include proper drainage, here are essentials that need to be built in from the start:
- Slope (Crossfall and Longitudinal Gradient)
- The road surface should be designed with a slight fall (crossfall) towards the edges or towards channels to shed water.
- Longitudinal gradient (along the road) must also allow flow—flat sections can trap water.
- Material choice and permeability
- Top surfacing materials should be water-resistant and seal cracks well.
- Base/sub-base layers must allow some percolation, or else include drainage layers (e.g. permeable layers, geotextiles).
- Using proper aggregate and compaction reduces voids that allow water ingress.
- Edge drains, kerbs, and gullies
- Where roads are bordered by kerbs or shoulders, inclusion of proper channels, edge drains or kerbs helps direct surface flow.
- Stormwater gullies (or catch basins) positioned at strategic low points to collect runoff.
- Subsidiary drainage features
- If road bed lies near high-water table, include underdrainage or French drains.
- Proper subsoil preparation and removal of soft material, so that water doesn’t accumulate beneath.
- Maintenance planning
- Drainage is not “install once and forget.” Leaves, debris, blockages must be cleared.
- Inspect joints and cracks regularly, reseal when needed.
- Maintain gullies and channels so they function well over time.
Best practices & tips for implementing drainage in surfacing works
- Always survey the terrain: detect natural water flow paths, ground water points, soil types.
- Work with civil engineers to design gradients & drainage layout early—don’t leave until paving is nearly done.
- Use quality sub-base materials (grit, gravel, stone) with good compaction to avoid water logging.
- Use impermeable or semi-impermeable surfacing at top layer plus sealants to reduce infiltration.
- Incorporate safety features: non-slip surfaces, checks for water ponding, reflective drainage covers.
- For rehabilitation projects, assess existing drainage issues (blocked drains, insufficient slope) and correct them.
How Total Surfacing Solutions applies drainage in its surfacing portfolio
At Total Suracing Solutions, we understand that no road surfacing project is complete without solid drainage design. Our process includes:
- Early-stage site surveys to assess ground slope, soil/water table, existing drainage.
- Designing gradients and specifying edge and channel drainage to ensure surface runoff is handled.
- Selecting sub-base and surfacing materials that resist water penetration and damage.
- Providing proper maintenance advice as part of handover, so drainage features continue to function optimally.
Benefits of investing in proper drainage
- Extended lifespan of the road surface: fewer repairs, less frequent resurfacing.
- Lower maintenance costs over time: less cracking, fewer potholes.
- Improved safety: less standing water reduces accidents, hydroplaning.
- Better user satisfaction: smoother, safer roads and paths.
- Environmental benefits: controlling runoff prevents erosion, water damage to neighboring properties.
Conclusion
Proper drainage in road surfacing is not optional—it’s essential for long-term durability, safety, and cost-effectiveness. By designing in slope, selecting suitable materials, including drainage infrastructure, and planning maintenance, road surfacing projects avoid many of the common causes of premature failure.
If you’re considering a surfacing project and want it done right—lasting well, safe, with minimal maintenance—reach out to Total Surfacing Solutions. We specialise in comprehensive surfacing solutions, including expert drainage design and installation, to ensure your roads, driveways or paved areas perform for years to come.
