Gloucester Rivers Improvement Project - River Twyver and Sud Brook

Overview

Part of this project is part-funded by the European Structural and Investment Funds

Working together, Gloucester City Council, the Environment Agency and Gloucestershire Wildlife Trust are beginning a three year project seeking to improve water quality and reduce flood risk, while also providing wider environmental benefits.

Project Objectives

The main four elements are:

• natural flood management (NFM) upstream of the M5 - working with local landowners to reduce nutrient runoff, and slowing flows
• river restoration - restoring sections of the Sud Brook and River Twyver to create more natural channels
• addressing motorway and urban drainage - Slowing down run-off from the M5, and reducing pollutants entering the rivers
• investigating other measures to reduce flood risk to properties

We are aiming to deliver the different strands by 2022. These will provide multi-benefits by tackling both water quality and flood risk issues.

Background to the Sud and Twyver River Restoration: why do these watercourses need improving?

The Sud Brook and River Twyver are very heavily modified waterbodies, running in concrete channels for much of their length. The water quality in both is affected by many factors, including:

• runoff from woodland and farmed areas in the upper sections of the streams/on the steep Cotswold escarpment (this can carry nutrients and silt)
• runoff from surrounding roads, including the M5 (this can carry oils, metals and silt)
• wrong connections into surface water drains which discharge to the rivers (these can carry washing machine, sink and toilet waste).
• occasional discharges of, for example, paint pot washings or car washings, from driveways and road drains.

The concrete channels and their steep sides limit habitat biodiversity, preventing wetland vegetation from establishing and providing refuges for aquatic invertebrates and fish.

Infographic showing the elements we are seeking to address, where and how

(If you hover your computer mouse over the graphic there will be options to zoom in to read the details more easily.)

Working in Partnership

The project will be delivered through a partnership approach. Gloucester City Council is the lead partner for the NFM and some of the river restoration elements, supported by the Environment Agency, Gloucestershire Wildlife Trust and Stroud District Council. Treating runoff from the M5 is being investigated by the Environment Agency and Highways England. The University of Gloucestershire is also supporting the project through monitoring and student dissertations.

Natural Flood Management (NFM) in the upper catchment

The River Twyver catchment starts life on the steep slopes of the Cotswolds above Upton St Leonards, with tributaries running off from Kites Hill and Prinknash, draining an area of approximately 6.7Km2.

Gloucester City Council, with funding through the DEFRA Community NFM Pilot Programme, are working with Gloucestershire Wildlife Trust and landowners to implement a range of river restoration and land management measures to reduce surface and soil run-off into the brooks.

Ten NFM woody structures have been installed on the tributaries on Kites Hill, in partnership with the World Land Trust. Extensive works have been agreed with Portway Farm, including NFM structures, livestock fencing and new water supplies to exclude cattle from the watercourse. In addition a programme of NFM measures have been agreed with the Prinknash Abbey Estate which will significantly reduce sediment entering the brooks, which ultimately impacts on the River Twyver and Saintbridge Pond. These works will be implemented in September 2019, to avoid conflict with the bird nesting season.

River Restoration on the Sud Brook - What we will be doing

The Sud Brook and River Twyver are no longer natural rivers - some sections are entirely in a concrete channel with steep-sided banks. As a result the rivers lack the habitats essential for fish and invertebrates to thrive. Over the next 3 years the project aims to:

• Remove the concrete channel in a section upstream of Heron Way: work is underway and progressing well
• Carry out landscaping of surrounding habitat to help to create more wetland habitat
• Create sustainable drainage features to intercept flows, slowing them down and reducing pollutants
• Improve biodiversity for native species
• Provide opportunities for local communities to get involved.

Improvements will happen in stages throughout the next 3 years and local residents will be consulted at each stage and kept informed.

Pictures showing the progress with works near Heron Way to remove the concrete channel:

Other measures to reduce flood risk to properties

The Environment Agency has permissive powers to carry out works on the River Twyver and Sud Brook to reduce flood risk. We have commissioned consultants to carry out computer-based hydraulic modelling to better understand flood risk from these watercourses and to help inform whether there are measures that could be undertaken to reduce flood risk with a contribution from public funding. This modelling and appraisal is continuing and we anticipate being able to update on this work in Autumn 2019.

The Environment Agency and Gloucester City Council do have many records of flooding, but we always welcome more to build on our knowledge and to incorporate into the modelling work. We would welcome additional information you may have on previous flooding in the area - for example photographs of previous floods (ideally with dates and locations). These can be sent to Environment Agency Engagement Team (FAO K Wise), Riversmeet House, Newtown Industrial Estate, Northway Lane, Tewkesbury, Glos GL20 or emailed to Engagement_WestMids@environment-agency.gov.uk.

We all have a part to play

The project partners encourage communities to value their local river and make the connection between the water in our rivers and the water we use at home.

Please also consider how you interact with the river and how habitat or flood risk may be affected. For example please do not put rubbish - including garden debris - into watercourses as this can cause blockages and increase flood risk.

Project Funding

Each element is funded by distinct sources. Across the whole project, some of these include:

• DEFRA NFM Community Pilot Programme: Upper Twyver NFM
• The European Structural Investment Funds (ESIF)
• Highway England’s Environment Designated Fund
• Flood and Coastal Risk Management Grant in Aid
• English Severn and Wye Regional Flood and Coastal Committee Local Levy

Engaging with communities

In early 2018 a public consultation was held throughout the catchment area to ask residents what they liked and didn't like about the Sud and Twyver watercourses. This also helped us understand how often the watercourses were used by the local community and what changes people would like to see. These results were used to inform the design of the first phase of the river restoration project. A further event was held in September to fine tune the proposed design of the works. The sessions were well attended and received by the community.

Two community event days were held in early 2019 during which local communities could learn about what is living in the rivers. Alongside this, in early 2019 a primary school education programme was delivered to schools in the area, teaching children about life in our rivers, and how they can help to keep them clean.

We have also held two training days for the local community, which have equipped residents with the skills to monitor the watercourses to assess what is living there and how the habitat changes over time. We hope to deliver further training courses as the project progresses.

Thank you for visiting. We will be updating this page every two months. Last updated 15 May 2019.