Foul Drainage Connection in Ireland — Mains Sewer, Treatment System, or Septic
On this page
A Pre-Connection Enquiry Form (PCEF) to Uisce Éireann is the first step for any new build. Costs €100–€300, with a decision typically in 4–6 weeks. The PCEF confirms whether a mains sewer connection is feasible and quotes the developer contribution (€5,000–€15,000 for residential). If a connection is feasible, that's the route for any site within reach of the network — it's cheaper and more reliable long-term than a treatment system. If no connection is feasible, you need a septic tank or treatment system per the EPA Code of Practice (2018, updated 2021). Get the percolation test before you sign contracts. The PCEF response is binding for 24 months and goes into the planning application pack.
TL;DR
Pre-Connection Enquiry Form to Uisce Éireann (formerly Irish Water) is the first step. Costs €100–€300, with a decision in 4–6 weeks.
If a connection is feasible, the developer contribution is €5,000–€15,000 for residential.
If no connection, you need a septic tank or treatment system per the EPA Code of Practice 2018. Get the perc test before you sign contracts.
When this matters most
You're choosing a site, or your design needs to confirm the foul drainage route.
When this doesn't apply
Your site has a confirmed Uisce Éireann connection agreement.
Frequently asked questions
How much is a Uisce Éireann pre-connection enquiry?
€100–€300. Decision typically in 4–6 weeks. The response is binding for 24 months and is required as part of the planning application pack.
Can I connect to a sewer without a Uisce Éireann agreement?
No. All new connections to the public sewer require a Connection Agreement from Uisce Éireann. Self-connections are illegal and can be enforced by the local authority.
What is a developer contribution for a sewer connection?
A one-off charge levied by Uisce Éireann to fund the upgrade of the downstream network. Typically €5,000–€15,000 for a single residential connection. Higher for commercial or multi-unit.
Sources
Uisce Éireann, Pre-Connection Enquiry Form and charges. https://www.water.ie/
Frequently asked questions
How much is a Uisce Éireann pre-connection enquiry?
€100–€300. Decision typically in 4–6 weeks. The response is binding for 24 months and is required as part of the planning application pack.
Can I connect to a sewer without a Uisce Éireann agreement?
No. All new connections to the public sewer require a Connection Agreement from Uisce Éireann. Self-connections are illegal and can be enforced by the local authority.
What is a developer contribution for a sewer connection?
A one-off charge levied by Uisce Éireann to fund the upgrade of the downstream network. Typically €5,000–€15,000 for a single residential connection. Higher for commercial or multi-unit.