Improving the river Lea

We are working with Luton Borough Council and local communities to improve the biodiversity and landscape of local chalk streams, a globally-rare habitat.

We will be undertaking river restoration work at The Moor between September and December 2019. A new river channel will meander further into the park with wetland areas created to increase flood capacity. A backwater will provide fish a refuge from high flows and pollution events. We apologise for any inconvenience this may cause.

 

A new river landscape through The Moor, with:

  • an improved appearance
  • enhanced opportunities to engage with the river
  • better habitats for fish, plants and invertebrates
  • an increased capacity for high flows in the river, reducing the likelihood of flooding to local properties

 

Currently the channel is generally over-wide, especially at the upstream end, and consequently sediment is deposited on the bed, smothering any gravel that may be present. This is a problem, as gravel is vital for the spawning of many fish species, such as trout, and also supports a wide range of invertebrates.

The steep right bank requires re-profiling to allow plants to become established and to reduce the amount of silt entering the river. Furthermore, the trees on the left (east) bank over shade the river, restricting the growth of in-channel and marginal plants. Below is the proposed design for the river restoration.

 

   Artist impression of the new layout of the river lea on the Moor

 

If you would like to find out more information about the project, please contact Jane Everett - jane.everett@affinitywater.co.uk

 

Completed Projects

Manor Road Park river restoration

It would be great to get your feedback - please click here to complete our quick survey and let us know your thought's about the river restoration.

Watch our video to find out more about the Manor Road Park river restoration.

 

Manor Road Park River Lea improvements - The challenge

The River Lea flows along the eastern edge of Manor Road Park in a deep, restricted channel. The riverbed is concrete and the river runs between concrete walls or steps with metal railings.

The way the river flows means that silt covers the natural gravels, making it harder for fish and other creatures to thrive. The high walls separate the river from the floodplain which can put other areas of the town at risk of flooding. Above all, the river is unwelcoming and hidden from the local communities who could be enjoying a rich natural environment.

 

How we improved the river

We worked with the Environment Agency and Luton Borough Council to agree on a proposal to improve the habitat and flow of the river, these included:

  • To improve the biodiversity value of the river to support a better variety of plants and creatures in the water and on the river banks.

  • To help the river stay healthy when water flows are low and reduce the local risk of flooding when flows are stronger.

  • To make the river safer for everyone.

  • To provide a pleasant and usable space for local people

 

What we've done:

  • Removed the concrete river bed and the concrete steps, tarmac path, concrete wall and metal railings;

  • Make the river narrower and more winding

  • Improved the riverbanks to give a stable slope to encourage a greater variety of plants on the bank and in the river and will not be at risk from erosion or collapse.

  • Removed some overhanging branches from the large trees to allow more light to reach the river and encourage more plant growth in the river and at the water's edge.

  • Re-connected the river to the surrounding environment by removing the concrete channel that confines the river along the edge of the park behind iron railings

  • Re-located the children’s playground to create the space to meander the river through the park.

 

The project was completed earlier in Summer and the benefits of this work are now starting to take shape. Please see below for before and after photos.

 

Manor Road Park Before Works Started Manor Road Park Construction Works May 2018

Vegetation growing alongside the river bank  Close up of vegetation growing along the river bank

If you have any queries concerning this project please contact Jane Everett the Project Manager on Jane.Everett@Affinitywater.co.uk

Moat Farm & Riddy Lane Allotments

The Moat Farm & Riddy Lane Allotment river improvement project was one of a number of projects that are taking place as part of the Revitalising Chalk Rivers partnership, in collaboration with the Environment Agency. These improvement works will help to restore and improve the habitat of chalk streams along the River Lea and rivers in other catchments.

 

Why did the allotment need to be improved?

The area where the river flows through the allotment gardens in Luton has been identified as a priority area for potential morphological mitigation works. The bank sides through this section are very steep, in places up to two metres deep, and are heavily shaded by trees and shrubs. The allotments themselves abut the river with no buffer margins, allotment plots have been extended into the riparian zone and used for storage of compost material, rubbish, and in some places the building of sheds. Some of the compost piles have collapsed into the river channel, which are a potentially serious source of pollution into the river.

Objectives:

  • To naturalise the River Lea in Luton as much as possible;

  • To improve biodiversity in the river corridor;

  • To help the river meet the requirements of the Water Framework Directive;

  • To make the river more resilient to low-flows;

  • To carry out tree works to cut back overgrown trees and shrubs, to allow sunlight to reach the river and its banks.

  • To re-instate a clear 3m riparian zone on the top of the river bank;

  • To remove and dispose of the compost heaps on the river bank;

  • To improve the river as an amenity feature for the allotment tenants;

  • To reduce the risk of flooding

 

What we've done:

The Allotment Committee staked out a 3m riparian zone along both banks of the river. The allotment plot tenants were asked to remove any sheds and personal items within the 3m zone.

Following a phase one habitat survey, a detailed tree survey, reptile surveys and Water vole surveys, tree works (felling, coppicing and pollarding) and scrub clearance commenced. These works will let light into the river channel and encourage plants to grow in the river channel and on the river banks, creating new habitats for insects and fish.

The heaps of compost and rubbish on the edge of the river banks were removed and the riparian zone re-instated to ground level. Around 140 tonnes of compost and rubbish was cleared from the top of the river banks and removed off site.

Signs have been erected to remind tenants to keep the 3m riparian zone clear of compost and rubbish.

We will continue to monitor the river for morphological and ecological responses to the river restoration works.