Percolation Tests now have to be carried out to determine the capacity of the soil on all Development Sites to satisfy SuDS (Sustainable Urban Drainage Strategy ) with their Investigations. This involves taking samples of the soil, their porosity, type and depth that is particular to the site. These Tests have to be carried out in accordance with Approved Document of Building Regs Part H2.
This is achieved by experimental digs to expose and test the soil at various depths and then testing the soil. Water has to percolate at a required rate for it to be sufficient to support any soakaways planned in the development even where pervious surface coatings are to be used.