Harrow's Streams

Streams in Harrow: the problem and what we will try to do

Click on the map for a higher resolution PDF.

Key to numbered locations. Click here for contact details of individual sites.
1. Riverside Park
2. Pinner Park Farm
3. Headstone Manor Park Features in our video tour of the Yeading Brook West
4 Yeading Walk Features in our video tour of the Yeading Brook West
5 Streamside Open Space Features in our video tour of the Yeading Brook West
6 Roxbourne Park Features in our video tour of the Yeading Brook West
7 Newton Farm Ecology Park
8 Newton Park West
9 Old Redding Nature Reserve
10 Bentley Priory Nature Reserve
11 Stanmore Common
12 Stanmore Country Park and Wood Farm
13 Stanmore Marsh
14 Woodcock Park

Several sections of the Yeading Brook West will be enhanced as part of Harrow Council's Yeading Brook Unbound project.
Two of London's rivers, the Pinn and the Crane*, rise in Harrow, while streams in the eastern half of the borough join together further downstream to form the river Brent. However for the most part we are unaware of these streams as they flow behind back gardens or under our feet in culverts. We are often only aware of them when they emerge to flow through parks and open spaces or, unfortunately, when they cannot manage the water flow, they will flood and damage homes and block roads.

There are a few places where these streams provide a pleasant public amenity. Chief among these are:
  • Summerhouse Lake in Bentley Priory Nature Reserve
  • The moat and wetlands at Headstone Manor Park and Headstone Manor Museum
  • The Yeading Brook West in Yeading Walk, Streamside Open Space and Roxbourne Park
  • The Yeading Brook East in Newton Park West
Unfortunately, however, the vast majority of our streams are ugly and highly polluted. Harrow Council is working with various London and national bodies to improve the situation. Some sections of streams have been successfully rewilded, that is, given more natural bends and contours. This slows the flow of water and helps prevent flooding downstream, with the channel and its banks supporting diverse native plants and animals.

However, while rewilded streams and restored habitat look better, poor water quality and recurring pollution mean they often support only a fraction of the wildlife that should be present. Harrow Nature Conservation Forum have been awarded a grant from Thames Water's Rivers and Wetlands Community Days Fund to survey Harrow's ponds and waterways, add to knowledge of our about them, work to improve them - and encourage you to get involved.

Misconnections: the source of the most serious pollution

Below Harrow's streets are two sets of pipes that together form a so-called “Separate Sewer System”. When this is set up properly, rain water from street drains and the roofs of buildings is collected in surface water drains which empty, without further treatment, into streams and rivers. Foul water from washbasins, showers, washing machines and toilets is collected into foul sewers that run to sewage treatment systems to be purified before release into streams and rivers.

There are many problems with the infrastructure in Harrow but the most serious cause of pollution is misconnections: the connection of waste pipes carrying foul water to surface water drains rather than foul water sewers. When most of Harrow's houses were built in the early 20th century the connections were made correctly. However more recent extensions, garden offices and illegal “beds in sheds” are all too often connected incorrectly, with builders connecting foul outflows into the first pipe they find without checking whether it is a foul or surface drain.

There's a good presentation by Thames21 about all these questions and how they can be helped by citizen involvement - click here to read a PDF.

* The Yeading Brook West and Yeading Brook East join downstream. A little further downstream the watercourse changes name and becomes the River Crane.

Return to the Watercourses Project home page

To Harrow Nature Conservation Forum home page