The Mersey Rivers Trust works in partnership with local authorities, government agencies, private companies and other charities to improve the River Mersey and its tributaries for people and wildlife. Residents can join in and help to look after their local river or stream by checking the plumbing connections in their home.

Correct connections

Most houses built after 1920 have a separate sewage system; one set of pipes takes rainwater that falls on a roof or in a garden directly to a local stream or river. A different set of pipes takes dirty water, from kitchens and bathrooms, to a sewage treatment works.

Correctly Connected House with a Separate Sewage System

A correctly connected house with a separate sewage system.

Check your plumbing

If your household plumbing is not properly connected dirty water could flow directly into your local river or stream. This is called a misconnection.

Misconnections can cause water pollution and happen when houses are built, when they are extended or when new household appliances are plumbed in.

A dirty water pipe is usually large and often has an air vent on the top, as shown in brown in the diagram below. The diagram also shows pipes from a bathroom and a domestic appliance correctly connected to the dirty water pipe.

Correct Connections to a dirty water pipe

Correct connections to a dirty water pipe.

Meanwhile, the diagram below shows two misconnections in red. Pipes, shown in blue, connected to a roof carry rainwater directly to a local river or stream. Pipes carrying dirty water, from a bathroom or a domestic appliance, should not connect to this pipe or to a rainwater drain.

Dirty water pipes incorrectly connected to a rainwater pipe and drain.

Dirty water pipes incorrectly connected to a rainwater pipe and drain.

If your house was built after 1920 please check your plumbing connections using the Trust’s handy leaflet.

Further information is available from the national Connect Right campaign at A trusted local plumber will be able to help you fix the misconnection. More information about plumbers in your area is available from Water Safe

If you see a serious water pollution incident please report it on the Environment Agency’s hotline on 0800 80 70 60.

Facts and figures about misconnections:

  • It is estimated that 500,000 properties in the UK have one or more misconnections.
  • 15% of our rivers are failing water quality standards due to misconnections or sewer related pollution. This problem is especially significant in urban areas such as Greater Manchester.
  • The most common cause of a domestic misconnection is an incorrectly connected washing machine. This type of misconnection accounts for approx. 35% of all domestic misconnections. 

If you live in the Cheadle Hulme area of Stockport and think you have spotted a misconnection as part of the Easter Hunt please email the Trust at  This email address is being protected from spambots. You need JavaScript enabled to view it. or call 0161 443 0886. Trust staff will be able to check whether you live in an area with a separate sewage system and offer further advice.