Drain rats are brown rats that live in and travel through the public and private sewer network, occasionally entering properties via defective drains, broken access covers or unsealed redundant connections. In London the issue is widespread because the Victorian and Edwardian sewer system provides extensive habitat. Sightings of rats indoors, scratching noises from WC pans, gnaw marks on drain covers and droppings in cellars all suggest an entry point. Engineers usually identify the entry route by carrying out a CCTV drain survey and looking for unsealed open ends, broken pipework or displaced joints. Sealing redundant connections, fitting non-return valves to risk fittings and repairing structural defects under BS EN ISO 11296 typically addresses the route. Eradication is normally handled by a pest control contractor working alongside the drainage engineer.
Drain rats (rat infestation in drains)
Brown rats living in and travelling through drains, sometimes entering properties via WC pans.
