Percolation Testing in Ireland

Understanding T-tests, P-tests, and hydraulic subsoil testing for planning applications.

How Percolation Testing Works

Percolation tests measure how quickly water drains through subsoil layers to determine if the ground can absorb treated wastewater effluent.

The standard EPA methodology utilizes specific tests depending on the site characteristics:

T-Test (Subsurface): Measures percolation characteristics at the depth of the proposed infiltration pipes.
P-Test (Surface): Conducted at shallow depth where low permeability subsoil or elevated water tables require a mound or tertiary polishing filter at ground level.