Case study:Test and Itchen River Restoration Strategy

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Project overview

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Status	In progress
Project web site
Themes	Environmental flows and water resources, Fisheries, Flood risk management, Habitat and biodiversity, Hydromorphology, Monitoring
Country	England
Main contact forename	Heb
Main contact surname	Leman
Main contact user ID
Contact organisation	Environment Agency
Contact organisation web site	http://www.gov.uk/government/organisations/environment-agency
Partner organisations	Natural England, local fisheries and riparian owners
This is a parent project encompassing the following projects	Old Station Beat restoration, River Test at Bossington, Test and Itchen River Restoration Strategy 2

A River Restoration Centre Members site visit (June 2014) where Test and Itchen Project Officer, Heb Leman (Environment Agency), explained the aims of the restoration strategy. Photo © RRC

Project summary

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The Test and Itchen River Restoration Strategy is a collaborative project between the Environment Agency, Natural England, local fisheries and riparian owners.

Presently the SSSI status of the Test and Itchen is in unfavourable condition. This is due to historic dredging, the number of structures, industry and historic management. The aim of the Strategy is to collaboratively work with landowners to restore both rivers so that they reach favourable condition in the future.

Up to June 2014, approximately 2km has been improved by bed raising, narrowing and encouraging a change in management. Five restoration projects were completed in 2013 and a further six are planned for 2014.

Project 1: River Test, Bossington Estate, close to Bossington Park (completed 2013)
At the Bossington Estate, the Environment Agency and Natural England have worked with Cain Bio-engineering to narrow the channel considerably (up to 40-60% in some sections) to restore a more natural river which has already led to significant improvement in the variety of river bed heterogeneity and in-channel habitats observed. The Estate have supported the project as they would like to attract anglers who prefer fly fishing in a more ‘challenging’ environment, than on other sections of the middle River Test, to offer this in the Test Valley. The total cost of the scheme was approximately £40,000 for 450m of restoration.

Project 2: River Test, Houghton Estate, close to Stockbridge (completed 2013)
The Houghton Club, one of the first fisheries to establish in England if not the world, has been open-minded. They agreed to modify historic bank management practices to enhance the channel and side channel scrapes have been created to reconnect the river to its floodplain in strategic areas. Selective channel narrowing has also taken place. Flooding in winter 2013/4 immediately showed the benefits of reconnecting the river with the surrounding land (which is designated SSSI). From a flood risk management perspective, holding water on this land prior to the river reaching Stockbridge was noted to have had a positive influence on flood risk reduction in the village. The project was jointly funded by the Environment Agency and the Houghton Estate.

Monitoring surveys and results

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Students at the University of Southampton are monitoring the Bossington Estate project, and are working with the Environment Agency on other sites too.

Lessons learnt

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The sections of river that have been restored demonstrate the contrasting approaches of contractors working on different sites (see Image Gallery). The extent of channel narrowing and restoration works take into account varying views of the landowners, the aspirations of the fishery and the requirement to improve the SSSI.

Image gallery

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Backwater/ fish refuge on the Park Stream, Bossington Estate (tributary of the River Test) ©RRC June 2014

Channel narrowing and bed raising on the Park Stream, Bossington Estate (tributary of the River Test) ©RRC June 2014

Gravel infill shows the width of channel narrowing (40-60% of pre-restored channel) on the Park Stream, Bossington Estate (tributary of the River Test) ©RRC June 2014

Clean gravels and excellent spawning habitat after channel narrowing on the Park Stream, Bossington Estate (tributary of the River Test) ©RRC June 2014

Post channel narrowing (looking upstream) on the River Test, Houghton Club estate ©RRC June 2014

Post channel narrowing (looking downstream) on the River Test, Houghton Club estate ©RRC June 2014

Catchment and subcatchment Select a catchment/subcatchment Site Edit site Name WFD water body codes WFD (national) typology WFD water body name Pre-project morphology Reference morphology Desired post project morphology Heavily modified water body National/international site designation Local/regional site designations Protected species present Invasive species present Species of interest Dominant hydrology Dominant substrate River corridor land use Average bankfull channel width category Average bankfull channel width (m) Average bankfull channel depth category Average bankfull channel depth (m) Mean discharge category Mean annual discharge (m3/s) Average channel gradient category Average channel gradient Average unit stream power (W/m2) Project background Edit project background Reach length directly affected (m) Project started Works started Works completed Project completed 2015/03/31 Total cost category Total cost (k€) Benefit to cost ratio Funding sources Cost for project phases Phase cost category cost exact (k€) Lead organisation Contact forename Contact surname Investigation and design Environment Agency Stakeholder engagement and communication Environment Agency Works and works supervision Post-project management and maintenance Monitoring Southampton University Reasons for river restoration Edit reasons for restoration Mitigation of a pressure Barriers to fish migration, Flood risk management, Impoundments (not hydropower), Land drainage, Riparian development Hydromorphology Channel pattern/planform, Continuity for organisms, Continuity of sediment transport, Freshwater flow regime, Quantity & dynamics of flow, Width & depth variation Biology Fish, Invertebrates, Macrophytes Physico-chemical Other reasons for the project Measures Edit Measures Structural measures Bank/bed modifications Bed raising Floodplain / River corridor Floodplain reconnection Planform / Channel pattern Channel narrowing Other Creation of refuge habitats for fish Non-structural measures Management interventions More sensitive channel maintenance Social measures (incl. engagement) Other Monitoring Hydromorphological quality elements Edit Hydromorphological quality elements Element When monitored Type of monitoring Control site used Result Before measures After measures Qualitative Quantitative Biological quality elements Edit biological quality elements Element When monitored Type of monitoring Control site used Result Before measures After measures Qualitative Quantitative Physico-chemical quality elements Edit Physico-chemical quality elements Element When monitored Type of monitoring Control site used Result Before measures After measures Qualitative Quantitative Any other monitoring, e.g. social, economic Edit Other responses Element When monitored Type of monitoring Control site used Result Before measures After measures Qualitative Quantitative Monitoring documents Upload monitoring documents Additional documents and videos Upload additional documents Additional links and references Edit links and references Link Description Supplementary Information Edit Supplementary Information