Well water treatment in Co. Laois

Private wells in Co. Laois

The 2022 Census counted 6,385 Laois households on a private well or other private source, the 5th highest share of the 30 county and city areas: 20.5% of the county and 19,758 people, up from 6,011 homes in 2016. Another 2,853 homes are on a group water scheme, and 69.0% are on public mains.

A household well is exempt from the drinking water regulations, so nobody checks it but you. The EPA advises testing at least once a year, and every system we fit in Laois is specified from a lab report.

What's usually in a Laois well

The Geological Survey of Ireland (GSI) sampled 50 public and group supplies for its Laois report, so these figures describe the water in the rock rather than individual household wells.

Bacteria, the biggest issue

The GSI calls faecal bacteria the most important groundwater quality issue in the county. 10 of 15 public supplies had faecal bacteria in raw water, and E. coli was regularly present in 13 of the 50 supplies, including 8 group schemes. It warns that in certain areas more than half of private wells are likely to be polluted, at least now and then. Thin soils, badly sited septic tanks and farmyards, landspreading and poorly built wells are the causes it lists. See our guide to bacteria in well water.

Hard to very hard water

Of the 50 supplies, 60% were very hard and 30% hard. In the GSI's words, water from the limestone is hard or very hard, so lime scale is likely to be a problem. The Portlaoise supply measured 394 mg/L, Kyle Spring 318 mg/L, groundwater around Rathdowney is very hard and around Durrow hard to very hard. The Slieve Bloom sandstone in the north-west gives softer water, moderately hard to moderately soft.

Iron and manganese

Iron and manganese were above the EU limit in 10 of the 50 sources. They're mainly natural, found under peat, in the muddy limestones, in the Old Red Sandstone and in the Castlecomer Plateau rocks of the south-east, where they consistently exceed the limit. The GSI's Offaly report also found high iron and hydrogen sulphide in private wells in the Calp limestone around Portarlington, which straddles the county border. Expect taste problems, orange staining and black specks.

Nitrate

The GSI named twelve nitrate priority supplies, among them Barrow House, Shanahoe, Durrow Convent, Emo, Cullahill and two at Ballinakill. The Swan on the Castlecomer Plateau was the only source it studied with no detectable nitrate. More in our nitrates guide.

What we usually fit in Laois

Most Laois wells need some or all of this line, in this order, with any stage the report doesn't call for left out:

1. Sediment filter to protect everything after it.
2. Iron and manganese filter, ahead of the softener so the metals don't foul it.
3. Water softener sized for very hard water.
4. UV disinfection if the report shows E. coli or coliforms, fitted last on the main line so the water reaching the lamp is clear.
5. Reverse osmosis at the kitchen tap, which also takes nitrate out of the water you drink and cook with.

On mains water and only bothered by limescale? See our water softener page for Co. Laois instead.

The well grant in Laois

Laois County Council runs the well grant through its Water Supply section (057 8664000). Form PWS 1a has to go in before any work starts, and form PWS 1b once it's finished, so apply first and fit second. A house connected to Uisce Éireann or a group water scheme doesn't qualify, and nor does one that has had a water supply grant in the past seven years. Bring the council your lab report and our itemised quote. Our guide to the private well grant covers the rest.