What is a soakaway?
A soakaway is an underground pit or permeable crate filled with gravel or aggregate that collects and drains surface water into the surrounding soil.
An underground pit or crate system designed to collect surface water from driveways, patios, and other hard surfaces before allowing it to percolate naturally into the soil. Soakaways are typically excavated below ground level and lined with permeable materials like gravel, shingle, or geotextile-wrapped crates that let water pass through while retaining soil particles.
In Cheltenham, where heavy rainfall can overwhelm traditional drainage systems, soakaways form a key part of permeable paving design. Water drains through porous paving materials (such as permeable asphalt, resin-bound gravel, or permeable block paving) and flows to the soakaway, where it gradually filters down into the earth rather than running off into storm drains or flooding the site. This reduces pressure on the mains drainage system and helps manage surface water at source.
The depth, size, and backfill material of a soakaway depend on soil type, rainfall rates, and the area of paving feeding into it. Clay soils drain more slowly than sandy or chalky soils, which affects soakaway performance. Proper installation requires assessment of ground conditions and often planning consideration. A well-designed soakaway keeps patios and driveways usable during wet weather while meeting building regulations for surface water management. Paving contractors familiar with local ground conditions can recommend whether a soakaway suits a particular site or if alternative drainage, such as a dry well or permeable membrane system, would work better. Driveway paving specialists in the area can advise on drainage solutions suited to your property.