Hard Water Information Sheet – SCC

Introduction

Hardness is a natural characteristic of water which can enhance its palatability and consumer acceptability for drinking purposes. Hardness in water is caused by the presence of naturally occurring minerals, calcium and magnesium. Both are non-toxic and do not make water unsafe to drink.

What Can I Do If I Have Hard Water-General Advice?

The main disadvantage of hardness is that it can cause the build up of limescale deposits on household appliances. There are a wide variety of products available commercially to limit the affects of water hardness on appliances. More information on the use of these products and the specific settings required for each appliance can be found in the instruction manual for your appliance.

Water Quality Limits

There is no specific limit for hardness under the Irish Drinking Water Regulations.

Hardness is generally expressed as mg/l CaCO3 units. The following is one of several arbitrary classifications of water hardness. 

  • Soft  Up to 50 mg/l CaCO3
  • Moderately Soft  51-100 mg/l CaCO3
  • Slightly Hard  101-150 mg/l CaCO3
  • Moderately Hard  151-250 mg/l CaCO3
  • Hard  251-350 mg/l CaCO3
  • Excessively Hard  Over 351 mg/l CaCO3

Water Hardness In County Sligo 

Please see below the average water hardness for each Public Water supply in the County.

PUBLIC WATER SUPPLYAVERAGE WATER HARDNESS (mg CaCO3/l)WATER HARDNESS DESCRIPTION
PUBLIC WATER SUPPLYAVERAGE WATER HARDNESS (mg CaCO3/l)WATER HARDNESS DESCRIPTION
Foxes Den Public Water Supply 100 Moderately Soft
Kilsellagh Public Water Supply 140 Slightly Hard
Killaraght Public Water Supply 485 Excessively Hard
Lough Easkey Public Water Supply 32 Soft
Lough Gill Public Water Supply 110 Slightly Hard
Lough Talt Public Water Supply 80 Moderately Soft
North Sligo Public Water Supply 140 Slightly Hard
Riverstown Public Water Supply 320 Hard
South Sligo Public Water Supply 180 Moderately Hard