Action for Silk Stream

“A project to help tackle the effects of climate change by making space for water, reducing flooding and improving water quality in the Silk Stream catchment for the benefit of communities and the environment”.

Action for Silk Stream is a partnership project, led by Harrow and Barnet Councils with involvement from Thames21, Thames Water, Environment Agency, Greater London Authority, Canal and River Trust, Brent Catchment Partnership, Friends of the Silk Stream Resident Group, Silk Stream Flood Action Group and others. The Action for Silk Stream project is funded by Defra as part of the £200 million Flood and Coastal Innovation Programmes which is managed by the Environment Agency. The programmes will drive innovation in flood and coastal resilience and adaptation to a changing climate

The project will explore opportunities to build new wetlands, restore stretches of river and create new areas of natural drainage to increase flood resilience as well as create a host of other benefits, including improved water quality, beautiful public spaces that will boost health and wellbeing and much needed habitat for wildlife.

The Silk Stream Catchment

The Silk Stream is a major tributary of the River Brent, rising on the Harrow Weald and Barnet Plateau and joining the Brent at the Welsh Harp Reservoir. It has several tributaries including Burnt Oak Brook and Edgware Brook. The Silk Stream is an important resource for wildlife and, along with Burnt Oak Brook, is designated a Site of Importance for Nature Conservation. Welsh Harp Reservoir where the Silk Stream meets the Brent is a Site of Special Scientific Interest due to the diversity of breeding water birds that it supports.

Flooding is a serious concern in the catchment and it’s estimated that over 1000 properties are at risk. As the catchment has become increasingly urbanised with natural vegetation replaced by hard surfaces, water is less able to soak into the ground and during intense rainfall events water levels can rise rapidly, causing flooding.

Pollution is another problem that affects the Silk Stream, coming from a variety of sources including plumbing misconnections and connectivity between the surface water and foul sewers. During high rainfall events the sewers reach capacity and these problems are intensified.

How will the project help?

Traditional approaches to managing flood risk have focused on concrete flood defences but there is a growing movement towards natural flood management (NFM) which works with nature to slow the flow of water entering rivers, create natural flood storage and reconnect rivers to their flood plains. The project will see the creation of new wetlands in several parks in the Silk Stream catchment which will help build flood resilience, among other things.

The project will see the creation of new wetlands in several parks in the Silk Stream catchment which will help build flood resilience, improve water quality, boost biodiversity and provide valuable blue/green spaces for people to enjoy.

Sustainable Urban Drainage Systems (SUDS) such as rain gardens will be created in the urban streetscape to help remove pollutants from road run-off and slow the flow of water entering the surface water sewer system.

The project will also enlist the help of Thames Water, using innovative ‘thermosensors’ to discover where surface water is entering the foul network as part of efforts to address sewer flooding and the serious issues pollution that affect the catchment.

By using a variety of solutions and looking at the catchment as a whole the project will create tangible environmental benefits and allow for learning that can help replicate these benefits across the broader Brent Catchment and beyond.