Businesses in Leitrim are being urged to carefully monitor their disposal of trade effluent into the county's water treatment system.
Trade effluent is any liquid waste such as oils, fats or grease generated from a business.
Irish Water is highlighting concerns over the heavy presence of the material in the wastewater treatment system in Drumshanbo among other towns and villages.
Large quantities of the liquids can form what is known as 'fatbergs' that result in unsuccessful water treatment and the pollution of local waterways.
Regional Operational Manager for Connacht, Anthony Skeffington says the pollution not only damages the environment but also can damage the water network:
"It has a detrimental effect, I heard something on radio yesterday, that only 20 of our 3,00 rivers have excellent status, and this is of concern.
So what we want to do is to appeal to business owners and the genrrtal public to be caeful about what goes down the sink and what goes into our sewers."