Yorkshire Water says river water is getting into its sewer network, causing it to overload.

BBC: UK floods: Disruption threat receding

Last year, across its entire 33, 500 mile (54, 000km) sewer network the firm said it had removed 2, 000 tonnes of grease.

BBC: Fat-eating bacteria put in Hull sewers to remove blockages

But water companies needed to invest in the sewer network to ensure untreated waste water was only released in urgent cases.

BBC: Charity warning over raw sewage discharge levels

The project, to be carried out by United Utilities, aims to upgrade the sewer network and improve the water quality of the River Lune.

BBC: Lancaster ?18m sewer upgrade meeting held

Built after a string of cholera epidemics in the 19th century by Joseph Bazalgette, an engineer in the heroic Victorian mould, the capital's 14, 000-mile sewer network was a triumph of engineering and a victory for public health.

ECONOMIST: The capital's overflowing drains are due for a big upgrade

We know that many people are unable to save up enough money to build a toilet in their home, and even if they could, landlords would not permit them and there is no sewer network to connect to.

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