Preventing water pollution

Water pollution can come from a number of different sources. Many solids, liquids and gaseous substances can cause pollution if they enter the water environment. Common pollutants include chemicals, oil and waste products. Even substances such as milk, which pose no risk to human health, can cause serious harm to the water environment.

You must have authorisation if you discharge anything other than clean, uncontaminated water to surface waters or groundwater. Surface waters include rivers, reservoirs and canals, and make up a small percentage of fresh water reserves. Groundwater is all water below the water table. Groundwater makes up the largest available reserve of fresh water.

This guide outlines the main causes of water pollution, and when businesses need to apply for surface water or groundwater authorisations. It also describes how to prevent water pollution incidents and gives tips on suitable drainage systems.