Case study:Langford Lakes project
This case study is pending approval by a RiverWiki administrator.
Project overview
| Status | Complete |
|---|---|
| Project web site | |
| Themes | Economic aspects, Flood risk management, Land use management - agriculture, Social benefits, Spatial planning |
| Country | England |
| Main contact forename | Nick |
| Main contact surname | Elbourne |
| Main contact user ID | User:NickRRC |
| Contact organisation | River Restoration Centre |
| Contact organisation web site | http://www.therrc.co.uk |
| Partner organisations | Wiltshire Wildlife Trust, English Nature, Enviroment Agency and Wild Trout Trust |
| Parent multi-site project | |
| This is a parent project encompassing the following projects |
No |
Project summary
This area comprises a series of large lakes with the River Wylye, a chalk stream, flowing through the centre of them. Langford lakes and the River Wylye are renowned for their popularity for angling but fish populations have declined over recent years. In an attempt to trap sediment and diversify flow, a number of natural materials have been introduced to the stream.
Monitoring surveys and results
Lessons learnt
Catchment and subcatchment
Edit the catchment and subcatchment details
(affects all case studies in this subcatchment)
Site
| Name | Steeple Langford |
|---|---|
| WFD water body codes | GB108043022550 |
| WFD (national) typology | Low, Medium, Calcareous |
| WFD water body name | Wylye (Middle) |
| Pre-project morphology | Single channel, Straight, High width:depth |
| Reference morphology | Sinuous, Pool-riffle |
| Desired post project morphology | |
| Heavily modified water body | No |
| National/international site designation | EU - Special Area of Conservation |
| Local/regional site designations | |
| Protected species present | No |
| Invasive species present | No |
| Species of interest | |
| Dominant hydrology | Quick run-off, Groundwater |
| Dominant substrate | Bedrock, Cobble, Gravel |
| River corridor land use | Extensive agriculture, Woodland |
| Average bankfull channel width category | 5 - 10 m |
| Average bankfull channel width (m) | |
| Average bankfull channel depth category | 0.5 - 2 m |
| Average bankfull channel depth (m) | |
| Mean discharge category | |
| Mean annual discharge (m3/s) | 0.30.3 m³/s <br />300 l/s <br /> |
| Average channel gradient category | |
| Average channel gradient | |
| Average unit stream power (W/m2) |
Project background
| Reach length directly affected (m) | 1000 m1 km <br />100,000 cm <br /> |
|---|---|
| Project started | 2002/10/01 |
| Works started | |
| Works completed | 2002/10/01 |
| Project completed | |
| Total cost category | |
| Total cost (k€) | Unknown"Unknown" is not a number. |
| Benefit to cost ratio | |
| Funding sources | Wiltshire wildlife trust, Natural England, Environment Agency |
Cost for project phases
| Phase | cost category | cost exact (k€) | Lead organisation | Contact forename | Contact surname |
|---|---|---|---|---|---|
| Investigation and design | |||||
| Stakeholder engagement and communication | |||||
| Works and works supervision | |||||
| Post-project management and maintenance | |||||
| Monitoring |
Reasons for river restoration
Measures
Structural measures
| |
|---|---|
| Bank/bed modifications | Planting, creation of a V weir, techniques to trap unwanted sediments - promoting eco. and geomorph. diversity. |
| Floodplain / River corridor | |
| Planform / Channel pattern | |
| Other | |
Non-structural measures
| |
| Management interventions | |
| Social measures (incl. engagement) | |
| Other | |
Monitoring
Hydromorphological quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
Biological quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
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
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
Monitoring documents
Image gallery
Additional documents and videos
Additional links and references
| Link | Description |
|---|---|
| http://publications.environment-agency.gov.uk/pdf/GESW0910BSTR-E-E.pdf | WFD Status for Wylye - See P. 1355. |
| http://www.therrc.co.uk/rrc case studies1.php?csid=30 | River Restoration Centre Case Study |
Supplementary Information
Edit Supplementary Information
RRC Visit Notes (2009):
Most of the examples of techniques in this river have only just been put into place (the official opening of the site was 28th September 2002). It is therefore, too early to establish which are likely to provide answers in terms of best practice and whether the increase in channel diversity will have a long term benefit for fisheries objectives.
Some concerns were raised during the site visit about the use of the v weir in this particular situation and it remains to be seen how successful/sustainable this will be compared to the more ‘natural’ diversity initiatives using on site materials over the longer term.
The faggots and pegs appear already to have trapped some sediment behind them. They are, however, very experimental and their height, in this case (approx 40-50cm), may ultimately be most critical to their long term success. Nevertheless they may provide a possible alternative to places where toe boarding or similar structural support has been used along other rivers.
This is an excellent site for viewing and discussing a range of techniques, and evaluating their effectiveness and suitability along chalk streams and elsewhere.