Well Yield Tests in Ireland — How to Confirm a Rural Water Supply Before You Buy
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Yield (litres per minute) is what matters, not depth. A 30–80 m borehole needs a 24-hour pump test to confirm flow.
Yield (litres per minute) is what matters, not depth. A typical Irish domestic well is 30–80 m deep, sometimes deeper on limestone, and yield varies from 5 L/min (marginal, you'll need storage) to 50+ L/min (plenty for a domestic house). A 24-hour pump test costs €600–€1,200 and confirms the sustainable yield. Get the test before you sign contracts — a dry well is a deal-killer, a marginal well is a €5k–€15k spec change (storage tank, larger pump, or both). Most rural Irish homes need 1,000–1,500 L/day. At 5 L/min, the well can supply 7,200 L/day but you'd need a 2,000 L storage tank to manage peak draw (morning shower + dishwasher). At 20 L/min, the well can supply 28,800 L/day without storage. A 50 m well is not necessarily a 20 L/min well; you need the pump test to know.
When this matters most
You're choosing a rural site with no mains water, or you've gone sale-agreed on one.
When this doesn't apply
Your site has a confirmed Uisce Éireann water connection.
Sources
Geological Survey Ireland, Groundwater resources. https://www.gsi.ie/
EPA, Drinking water guidance for private supplies. https://www.epa.ie/
Frequently asked questions
How much does a well yield test cost in Ireland?
€600–€1,200 for a 24-hour pump test. Includes a drawdown test, recovery test, and a report on sustainable yield. Most drillers do this in one visit.
How deep is a typical Irish well?
30–80 m on most Irish geology. Deeper on limestone (up to 150 m). Depth is not the limiting factor — yield is.
What is a good yield for a domestic well in Ireland?
20+ L/min is comfortable. 5–20 L/min is workable with storage. Below 5 L/min is marginal and may need a second well or larger storage.
When this matters most
You're choosing a rural site with no mains water, or you've gone sale-agreed on one.
When this doesn't apply
Your site has a confirmed Uisce Éireann water connection.
Where to go next
Next decision
The next step in your build sequence.
- Foul Drainage Connection in Ireland — Mains Sewer, Treatment System, or Septic →
- Is My Site Buildable in Ireland? The Five Checks That Decide It →
- Land Registry Check in Ireland — Folio, Map, and What to Look For Before You Buy →
- On-Site Electricity for a Self-Build in Ireland — Temporary Connection, Generator, or Solar →
- Ribbon Development in Ireland — The Planning Policy That Refuses Houses Along Rural Roads →
- Site Access in Ireland — Road Entrances, Sightlines, and the Road Opening Licence →
- Site Office and Welfare for a Self-Build — What You Need by Law (SHWW 2013) →
- Site Security on a Self-Build in Ireland — Hedges, Hoardings, CCTV, and Insurance →
- Site Survey in Ireland — Topographical, Measured, and Boundary Surveys →
Branch into
Adjacent decisions at the same stage.
- Flood Risk Maps in Ireland — How to Check opw.ie Before You Buy a Site →
- Percolation Tests in Ireland — EPA T-values, What They Mean, and What Costs When You Fail →
- Rural Housing Policy in Ireland 2026 — Local-Needs Tests and How Counties Vary →
- Septic Tank vs Mains Sewer in Ireland — When Each Applies and What It Costs →
Watch out for
Common mistakes, hidden costs, gotchas.
- Percolation Tests in Ireland — EPA T-values, What They Mean, and What Costs When You Fail →
- Septic Tank vs Mains Sewer in Ireland — When Each Applies and What It Costs →
- Site Assessment Cost in Ireland — Soil Test, Percolation Test, Water Test, and What to Order Together →
- Site Purchase Costs in Ireland — Stamp Duty, Legal Fees, and What Adds Up →
- Irish Soil Classification — Class 1 to Class 5+ and What Each One Costs You in Foundation →
Compare with
Alternative approaches worth knowing.