§ Mr. Gardiner
To ask the Secretary of State for Environment, Food and Rural Affairs what powers water companies have to stop(a) companies and (b) residential properties discharging pollutants into waterways. 
§ Mr. Morley
Water companies do not have any powers to stop companies or residential properties discharging pollutants into waterways. Their responsibility, under the Water Industry Act 1991, is to regulate trade effluent discharges made to public sewers.
Responsibility for controlling discharges to waterways belongs to the Environment Agency (the Agency). Under section 85 of the Water Resources Act 1991 (as amended by the Environment Act 1991) it is an offence to cause or knowingly permit polluting matter to enter "controlled waters", that is rivers, estuaries, coastal or groundwaters without permission. This is obtained as a discharge consent granted by the Agency. The Agency sets consent conditions which control volumes and concentrations of particular substances or imposes broader controls on the nature of the effluent. Each consent is based on an objective set by the Agency for the quality of the stretch of water to which the discharge is made as well as taking into account any relevant statutory requirements.