Drain — Poor Drainage

Poor Surface Drainage

Poor surface drainage can result from a blocked outlet, a reversed fall, a damaged crossing or local depressions. Grading should follow the identified cause.

Before moving material

Trace water from its entry point to the receiving outlet.

Receiving operation and checks

Inspect the drainage route during a suitable water event. Check that the complete route remains connected through boundaries and crossings.

Surface grading cannot remedy every subsurface drainage problem.

Surface Drainage Formation

Surface drainage formation gives runoff a connected route. Forming a depression without checking its outlet can simply relocate the ponding.

Before moving material

Identify catchment entry, the receiving outlet and levels along the route.

Receiving operation and checks

Stabilise the surface and inspect it during a suitable water event. Check continuous drainage through every join and crossing.

A grading pass does not size a drainage system or authorise discharge onto another property.

Drain Construction

Drain construction combines a designed invert with stable sides and a functioning discharge point. A scraper may form accessible shallow sections, while deeper or confined work may need an excavator.

Before moving material

Set out the route and locate utilities and crossings.

Receiving operation and checks

Finish side shaping, stabilisation and crossing details with the appropriate equipment. Survey invert levels at joins and the receiving end.

Depth, stability and discharge requirements can put the task beyond a compact scraper.

Record the job inputs

Use this checklist to turn the scenario into a specific brief. Retain the design revision and agree who accepts each completed layer.

• Existing condition, extent and the reason for intervention
• Required finished purpose, receiving operation and acceptance criteria
• Material type, layer role, source, receiving area and volume state
• Reference levels, datum, survey method and issued design revision
• Available tractor, implement configuration, travel route and turning space
• Checks before work, stopping points and evidence retained at handover

Checklist ticks apply only while this page is open. Include the completed brief in your project records.

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Surface and verification · Applications and rental · Equipment and technology