The Environmental Protection Agency (EPA) has published its new Code of Practice to allow more sites in ROI to find an on site wastewater solution.
The 2021 Code of Practice for Domestic Waste Water Treatment Systems (Population Equivalent ≤ 10) was published on 24th March 2021 and will come into force on the 7th of June.
The 2021 CoP is a result of a public consultation process that started in 2018.
The 2009 Code of Practice will continue to be used for site assessments and subsequent installations commenced before 7th June 2021, or where planning permission has been applied for before that date.
The new guidelines mean that self-builders whose site was unsuitable for development may now be able to find a solution for on site wastewater treatment. The maximum you can get on your percolation test, or T value, has been increased from 90 to 120.
However, this higher threshold isn’t high enough to provide solutions for all sites.
Self-builders in ROI who cannot connect to a mains wastewater system (through Irish Water or a group water scheme) and who fail the percolation test, cannot in practice obtain planning permission.
Compliance with the EPA’s Code of Practice is required under the Building and Planning Control systems.
The Code of Practice makes provisions for applying for a licence under the Water Pollution Act to discharge to a waterway after treatment, as is possible in NI. But in practice these licences are near impossible to get from the local authorities.
According to the Irish Onsite WasteWater Association, the most significant changes to the 2009 Code of Practice are:
Additional options in low permeability soils: The maximum allowable percolation value for domestic waste water treatment systems discharging effluent to ground was 75 under the 2009 Code. Low permeability soils not meeting this limit were unsuitable. The 2021 Code provides two new options for low permeability soils:
Drip dispersal: They can be used in low permeability soils up to a percolation value of 120.
Low-pressure pipe distribution: They can be used in low permeability soils up to a percolation value of 90.
Willow bed evapotranspiration systems: These can be used for secondary treatment of effluent with an offset tertiary soil polishing filter.
De-sludging calculator: The 2021 Code provides a table for working out the de-sludging frequency based on the number of people in the house and the size of the tank