Well water treatment in Co. Longford

Private wells in Co. Longford

The 2022 Census counted 1,670 Longford households on a private well or other private source, 10.3% of the county and 4,730 people. That's up slightly from 1,644 homes in 2016. Another 1,361 homes are on a group water scheme, and 78.8% are on public mains.

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

What's usually in a Longford well

The Geological Survey of Ireland (GSI) has no county groundwater report for Longford, so what follows comes from its reports on the individual groundwater bodies, based mostly on council and group scheme sources rather than household wells. Private wells in the same rock usually share the same water.

Hard to very hard water

Across much of the county the rock is impure limestone, sandstone and shale, and the GSI puts the groundwater there at hard to very hard, typically 380 to 450 mg/L. Along Lough Ree around Lanesborough it describes the karst limestone water as slightly hard to very hard and warns that lime-scale can be problematic. Trial wells just north of Longford town measured 246 to 394 mg/L, and the Slawn spring at Newtown Cashel 280 to 460 mg/L. The older Ordovician rock in the north has given anything from soft to moderately hard water where the GSI has sampled it elsewhere.

Iron, manganese and a rotten-egg smell

In the impure limestones and the sandstone and shale, the GSI says iron and manganese frequently fluctuate between zero and more than the EU limits, and hydrogen sulphide can often reach unacceptable levels. Both metals were over the limit in the 1999 trial wells near Newtownforbes, and at Newtown Cashel in 1996. Iron shows as orange or brown staining, manganese as black specks, and the sulphide as a rotten-egg smell, usually worst from the hot tap.

Bacteria

The GSI calls the karst limestone around Lough Ree highly vulnerable to pollution from septic tanks, farmyards, landspreading and streams that sink underground. At the Slawn spring at Newtown Cashel, an EPA monitoring point, faecal coliforms turned up in half of all samples, with gross contamination three times, which the GSI links to fast travel through the cracked limestone. You can't see, smell or taste bacteria, so only a lab test tells you. See our guide to bacteria in well water.

What we usually fit in Longford

Most Longford wells need some or all of this line, in this order, with any stage the report doesn't call for left out. On water this hard, pH correction is rarely needed.

1. Sediment filter to protect everything after it.
2. Iron and manganese filter, which takes the rotten-egg smell too. Both metals foul a softener if they reach it.
3. Water softener sized for water that can run past 400 mg/L.
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 for drinking water, if you want it.

For a rough idea of prices, see what well water treatment costs in Ireland.

The well grant in Longford

Longford County Council's Water Services section administers grants for the provision and improvement of individual water supplies, listed on its Water Schemes page. Ask Water Services for the form and terms before any work starts. 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 explains the rest.