Percolation Tests
Where it is intended to develop a new dwelling at a location where there is no Sewerage System, generally outside of the towns and villages a Site Characterisation Report (SCR) needs to be carried out at an early stage in the planning process. The objective of a site characterisation is to obtain sufficient information to determine if the site can be developed for an on-site wastewater system. Characterising the site involves a number of stages. These should include:
- A desk study, which collects any information that may be available on maps about the site. More recently, the EPA and local authorites have made available digital resources. This information includes soil and subsoil type, bedrock, aquifer classification, vulnerability of the bedrock, groundwater flow, source protection areas, and in some cases the history of previous SCR in that area.
- A visual assessment of the site, which defines the site in relation to surface features;
- A trial hole to evaluate the soil structure, depth to rock and water table
- Percolation tests.
In Ireland, the wastewater from over one third of the population – principally those living in dwellings not connected to municipal sewers rely on systems designed to treat the wastewater at or near the location where it is produced. These wastewater treatment systems are called on-site systems.