Soakaway installation in Bradford

Gravels in the valley, clay on the slopes

The Aire between Keighley and Shipley and the Wharfe around Ilkley have left sand and gravel terraces along their valleys, and that kind of ground can drain freely. The slopes above are often mantled in glacial clay over Coal Measures or Millstone Grit, which is far less helpful. Up on the gritstone, water can find its way through joints in the rock where there is little soil over it.

The upshot is that two sites in the same village can need different answers. Your engineer's tests settle which one yours is, and we build to their drawing whichever way they come out. Where peat or thick clay caps a hillside, infiltration rarely comes into it.

Groundwater near the river

On the valley floor, the gravels that drain well are also where groundwater can sit high, particularly in a wet winter. A soakaway needs a gap between its base and the water table, and that separation is part of the design your engineer produces. We build to the depth they set and look for standing water in the pit before starting.

The installation itself

Your groundworker forms the pit and later backfills it. In between, our crew:

• Checks the base is level, firm and clear of debris
• Lines the pit with a permeable geotextile so silt stays out
• Builds the crate structure up to the designed volume
• Connects the inlets and the catchpit or filter upstream
• Wraps the top, records the inspection and hands the pit back

Village plots and barn conversions

A good share of Bradford soakaway work comes from outside the city: new homes and barn conversions around Wilsden, Cullingworth, Silsden and Burley-in-Wharfedale, where there may be no surface water sewer to connect to. Infiltration is often the first option tried there, as the SuDS hierarchy expects.

Access on these jobs can be tight: a farmyard gate, a lane between drystone walls, a garden reached only on foot. Crates are light and modular, so they can be carried in by hand where a lorry can't reach.

Silt from farm tracks and yards is the biggest threat to a rural soakaway, so the catchpit ahead of it should sit somewhere the owner can actually get to with a bucket or a suction hose.

In the inner city the story is usually different, with clay and old mill land pointing to attenuation instead. We install both, so the drainage can follow the ground.