Episode 1

E1

In Cumbria, an army of engineers are replacing parts of an ageing monster underground pipeline that transports millions of litres of water from Haweswater Reservoir to 2 million people every day.

Episode 2

E2

Waste Warriors James and Andy battle to clear a newly formed fatberg underneath a busy street in Manchester. It is a monstrous mass of waste and fat that is 50 metres in length

Episode 3

E3

In Cumbria, John and his army of engineers are midway through a mammoth plumbing job, replacing parts of an ageing monster underground pipeline

Episode 4

E4

Geoff and his elite squad of sewage cleaners must scour the pumps deep inside a holding tank at Southport Treatment works, to ensure the waste doesn't back up into people's homes

Episode 5

E5

Project director John and his team undertake a crucial test at a fresh water pipeline in the Lake District, and a garden in Rucorn, Cheshire, is being slowly submerged in sewage.

Episode 6

E6

Steve and Mark face one of their toughest jobs ever and Stu and Ian tackle a potential pollution emergency.

Episode 7

E7

Stuart tackles a 200-metre fatberg in Manchester, newly qualified "leak listener" Dan detects holes in the water company's network, and the Steves attract donkey attention.

Episode 8

E8

The largest fatberg ever seen in the North West is proving an unbeatable enemy. At 400 tonnes and 350m long, it fills 40% of the main sewer system in the docks area of Liverpool.

Episode 9

E9

In North Wales, engineer Luke and his team of mega plumbers are mid way through a project to replace a problematic two km section of pipe that has a history of large bursts.

Episode 10

E10

In Liverpool city centre, a crack team of drainage engineers goes underground to clear a blocked sewer.

Episode 11

E11

Docuseries following the workers who maintain Britain's water systems.

Episode 12

E12

Docuseries following the workers who maintain Britain's water systems.