Welsh Water is the regulated company that provides water supply and sewerage services to over three million people living and working in Wales and some adjoining areas of England. They have 1.2 million household customers and over 110,000 business customers making them the sixth largest of the 23 regulated water companies in England
Welsh Water employs assets worth over £13 billion, which is more than £10,000 for every one of our household customers.
They operate 84 impounding reservoirs,106 water treatment works and supply an average 900 million litres of water every day through a network of 26,800km of water mains, including 620 pumping stations and 740 service reservoirs. We also collect waste water (and surface drainage) through a network of 17,600km of sewers, incorporating 1,650 sewage pumping stations and 3,000 combined sewer overflows. It is treated at 850 waste water treatment works located next to rivers and along the coast of Wales.
Wales boasts the wettest inhabited place in the UK, eight of the wettest towns, and the wettest city. The average yearly rainfall in the City of Swansea ranges from 43 inches at The Mumbles, and 48 inches in the city centre, to 56 inches in its northernmost suburbs such as Ynysforgan. The City of Cardiff is roughly 15 percent drier. In north Wales, Blaenau Ffestiniog, famous for its slate quarries and slate-grey skies, is second only to Fort William (Scotland) for rain amongst Britain's towns, with an annual average of 79 inches - more than twice what Manchester gets. The eastern flank of Snowdon is amongst the wettest places in the country, with a yearly average of at least 180 inches.
Given Wales's hilly character, and exposure to the prevailing south-westerly winds, which bring so much of the UK's rain, these statistics are hardly surprising. But to the lee of the hills - in what is known as a "rain shadow" region - there are some fairly small areas of markedly low rainfall. Less that 30 inches falls on average along the north Wales coast from Llandudno to the Dee estuary, throughout the Vale of Clwyd, and around Wrexham, Buckley and Shotton. At Rhyl the long-term mean is 25.8 inches, and at Hawarden Bridge (just across the River Dee from Chester) it is just 24.3 inches - about the same as London and Norwich.
This north-eastern quarter, remote from the tempering influences of the Atlantic Ocean, is also home to the most extreme temperature readings recorded in Wales. On December 13, 1981, the mercury sank to minus 23°C, while the blistering sunshine that saw records tumbling across most other parts of the UK in early August 1990 saw a record established for Wales, too: 35.2°C at Hawarden Bridge on August 2. The north Wales coast has also seen some extraordinary out-of-season heat waves, thanks to the föhn effect whereby warm moist air blowing across Snowdonia dries out and warms further as it descends the lee slope. Thus Aber, near Llandudno, has recorded 18.3°C in January and 21.3°C in November.