Ashton House

67 Compton Road



Soakaway Testing

Soakaways have long been used to dispose of stormwater from buildings and paved areas located away from a public sewer or watercourses.  However, over the last ten years there has been a significant change by the Environment Agency and Planning Authorities to limit the rate of discharge from new developments and the impact on watercourses.  Taking also into account the likely effects of climate change, soakaways and sustainable drainage systems are now seen as the preferred option in urban areas even where access is available to the local sewer network.


The regulators are increasingly asking for it at planning and pre-construction stage.


To aid in the design of the soakaway, GIS can carry out in-situ testing to determine the soil infiltration rates of the near surface strata, all in accordance with BRE Digest 365.


Following the excavation of a trial pit of sufficient size to represent a section of the design soakaway, the excavation is then filled with water three times in quick succession whilst monitoring each time the fall of discharge versus time until near empty.  The soil infiltration rate if calculated from the time taken for the water level in the excavation to fall from 75% to 25% effective depth.  The lowest of the three infiltration rates is used in the design for the new soakaway whether it be in a square/circular form or of the trench type.



Call today to discuss your site's soakaway testing needs:

01902 717 653

ground investigation being carried out County Tractor Soakaway Soakaway-1