Northumbrian Water Limited operates in the north east of England, trading as Northumbrian Water, and in the south east of England, trading as Essex & Suffolk Water.
Covering a combined area of over 12,260 square kilometres, the company operates 29 impounding reservoirs, 57 water treatment works, 359 water pumping stations, 338 water service reservoirs and 25,624 km water mains. In the north-east. NWL provides water and sewerage services to 2.7 million people. Here the company operates 414 sewage treatment works, 731 sewage pumping stations and 33,000 km sewers.