Drainage & Soakaways — Levels, Falls, Testing & Reinstatement
Reliable drainage protects your property in Haslemere and the finishes you’ve invested in. We begin with levels and surveys, confirm existing routes and capacities, and design foul and surface-water solutions that actually work on your site. Falls, bedding and junctions are set out carefully so pipes self-clean; chambers are positioned for access; and soakaways or attenuation are sized from real test data, not guesswork. Every trench is neat, services are protected, and reinstatement blends back into paving, tarmac or lawns. Before handover we test and record the installation, so approvals and future maintenance are straightforward.
Surveys & Percolation
A quick look rarely tells the whole story. We take invert levels at existing chambers, measure gradients and depths, and map routes and constraints (trees, foundations, utilities). For surface water we assess roof or paved areas and where water can discharge safely. If infiltration is possible, we carry out percolation tests to BRE365 to size soakaways correctly. Where it isn’t, we discuss attenuation and controlled outfalls. Early clarity avoids undersized pipes, standing water and costly rework, and it ensures that later paving and landscaping tie neatly into the drainage plan.
Invert Levels, Gradients & Falls
We work from the downstream control back upstream, taking inverts with a staff and laser so falls are known, not assumed. Pipes are then designed to self-clean—steep enough to move silt, not so steep they scour. Where cover is shallow, we’ll protect lines with slabs; where depths change, we step neatly at manholes. Recording inverts and gradients gives Building Control confidence and lets future contractors understand the system without exploratory digging.
BRE365 Percolation Tests & Design
Infiltration systems only work if they’re sized from real ground data. We dig trial pits, saturate the soil and time the drain-down as BRE365 requires. From this we calculate soakaway volume, crate configuration and minimum distances from buildings, boundaries and trees. If results are marginal, we’ll propose larger footprints, secondary discharge paths or switch to attenuation with a controlled outlet. A short test up front prevents expensive digging and revisiting later, ensuring reliable systems for homeowners across Haslemere.
Foul Drainage
Foul lines need smooth entries, stable bedding and accessible chambers. We set out routes to avoid sharp bends and clashes, choose junctions that maintain flow, and keep pipe gradients within guidance. Chambers are placed where changes of direction or level occur, with benching that directs effluent cleanly to the outlet. Rodding eyes are added at sensible intervals for maintenance. The outcome is a tight system that clears easily and resists settlement, smells and blockages.
Pipe Bedding, Junctions & Connections
Pipes are laid true on granular bedding to the manufacturer’s detail, haunched correctly and backfilled in layers so they stay put. Junctions are swept, angles sensible, and connections to existing runs made with adaptors or saddles suited to the pipe materials. We avoid kinks, reduce fittings, and keep access in mind, so you get a robust line that performs and is simple to maintain.
Manholes, Rodding Eyes & Testing
We use PPIC bases for speed and watertight joints, or brick/concrete chambers where depth or geometry demands. Benching is smooth with fall to the channel; covers are load-rated and set flush with the finish. Rodding points are positioned upstream of bends or where access would otherwise be awkward. Before backfill, lines are air- or water-tested so defects are caught while fixes are easy.
Surface Water Management
Moving rainwater away cleanly protects paths, thresholds and planting. We size channels, gullies and pipework from roof and hardstanding areas, then set falls so water reaches collection points without ponding. On drives we integrate ACO channels neatly at garage thresholds; around patios we set discrete slot drains or falls to lawn where appropriate. Where outfall capacity is limited, we add attenuation to slow peak flows and prevent overwhelm during heavy rain.
Gullies, ACO Channels & Drive Drainage
We install trapped gullies at downpipes to keep smells out, and ACO/slot channels with correct edge restraints and bedding so they sit firm and quiet under traffic. Grates are chosen to the load class and style of the surrounding finish. Levels are coordinated so water sheds naturally towards collection, not back to the house.
Attenuation & Flow Control
Where discharge needs throttling, we specify crate tanks wrapped in geotextile with a flow control (orifice or vortex) to the outlet. Inlets and overflows are detailed, inspection points provided for maintenance, and backfill compacted evenly. This keeps peak runoff in check and protects downstream systems, while leaving the surface free for paving or planting.
Soakaways & Crate Systems
When the ground allows, soakaways dispose of surface water on site. We build crate systems to the BRE365 result, wrapped in geotextile to stop fines, with inlet/outlet arrangements that spread flow across the tank. Locations respect minimum offsets from buildings and boundaries, and depths are balanced with groundwater and available cover. Access pipes are included for periodic inspection so the system keeps working year after year in Haslemere and the surrounding areas.
Geotextiles, Backfill & Maintenance Access
Clean, angular stone and proper geotextiles make or break performance. We use non-woven wraps with taped laps, protect membranes during placement, and compact backfill in layers to avoid settlement. Rodding/inspection points are brought to the surface in discreet covers so a jetter can reach the crate if needed. Done once, done right.
Reinstatement & Commissioning
Once lines are proven, we reinstate finishes to blend with the existing. Blocks go back on sharp sand with original patterns matched; tarmac is laid in bound layers; lawns are re-soiled and turfed. Frames sit level, joints are tight and edges are clean. We then commission—running water to confirm falls, checking traps and clearing the site—so you’re left with drainage that works and surfaces that look untouched.
Air/Water Tests & CCTV (as required)
Air tests quickly flag joint issues on new runs; water tests verify watertightness over longer lengths or for adoption. Where existing drains are tied-into, CCTV confirms condition, alignment and gradient, and provides a baseline video for the record. Any snags are corrected immediately and retested before handover.
Why Choose DM Jones Contractors
- ✓ Levels, gradients and capacities checked before we dig—no guesswork.
- ✓ BRE365 percolation tests with soakaway/attenuation sized from real data.
- ✓ Correct bedding, falls and junctions for self-cleansing, low-maintenance runs.
- ✓ Neat chambers with smooth benching and load-rated covers set flush.
- ✓ Channels, gullies and thresholds detailed so water sheds away from the house.
- ✓ Clean reinstatement that matches existing paving, tarmac or lawn.
- ✓ Tests, photos and simple as-builts for approvals and future maintenance.
- ✓ Tidy sites, clear timelines and fair, itemised pricing.
Book a Drainage Survey
Send a sketch or a few photos showing problem areas, existing chambers and where water currently goes. We’ll visit to take levels, advise on the best solution for your ground and budget, and provide a clear, itemised quotation with programme and reinstatement details. For homeowners in Haslemere, this means straightforward advice and drainage systems that work long-term.
