Case study:River Adur - Shipley weir removal

From RESTORE
Jump to: navigation, search
5.00
(one vote)


To discuss or comment on this case study, please use the discussion page.


Location: 50° 59' 3", -0° 22' 1"
Edit location
Loading map...
Left click to look around in the map, and use the wheel of your mouse to zoom in and out.


Project overview

Edit project overview
Status Complete
Project web site
Themes Fisheries, Flood risk management, Habitat and biodiversity, Hydromorphology
Country England
Main contact forename Gareth
Main contact surname Williams
Main contact user ID User:Glwilliams
Contact organisation Environment Agency
Contact organisation web site
Partner organisations Ouse and Adur Rivers Trust, Royal HaskoningDHV
This is a parent project
encompassing the following
projects
Shipley weir

Project summary

Edit project overview to modify the project summary.


The Adur Restoration of Physical Habitat Action plan (ARPHA) aims to improve riparian habitats, restore natural river and floodplain processes, reduce downstream flooding and improve biodiversity.

The latest success for this project is the removal of Shipley tilting gate. This Environment Agency owned and maintained structure on the Knepp estate on the Western arm of the Adur was preventing fish passage and impounding the river upstream. In partnership with the Ouse and Adur Rivers Trust (OART) the South Downs Fisheries and Biodiversity team led a project to remove the gate and stabilise the clay banks with brushwood terracing. This not only removed a significant barrier to fish passage but it has also helped restore natural river processes which will be beneficial to wider biodiversity as whole. The Arun and Adur operations field team with specialist help from the Ouse operations field team were the main contractors. Using their experience of the Knepp restoration project just downstream they carried out a very professional job and were praised by the designers, OART and everyone else involved with the project. The Arun and Adur Asset Performance Team helped with the engineering aspect as well as contractor management and finance.

This project has achieved Water Framework Directive (WFD) objectives for this waterbody and is an excellent example of another successful partnership project with OART.

Monitoring surveys and results

Edit project overview to modify the Monitoring survey and results.


A fish survey was carried out before the structure was completely removed and this data will be used to compare future surveys and monitor the effects this project has had on the existing fish communities and whether the work has increased the diversity of species present in this stretch of the Adur.

Lessons learnt

Edit project overview to modify the lessons learnt.


Starting this project late in the year meant we had had to pull out when the weather turned. The welfare unit left on site was repeatedly flooded costing the project up to £40,000. Lesson learnt, try and secure funding as early as possible so you can programme the works to co-incide with the nice weather.


Image gallery


Shipley weir in Winter
Dam removal
Digger work
Restored section looking downstream
ShowHideAdditionalImage.png


Catchment and subcatchment

Catchment

River basin district South East
River basin Adur and Ouse

Subcatchment

River name R. Adur West
Area category 10 - 100 km²
Area (km2)
Maximum altitude category Less than 100 m
Maximum altitude (m) 85
85 m
0.085 km
8,500 cm
Dominant geology Calcareous
Ecoregion Great Britain
Dominant land cover Improved grassland
Waterbody ID GB107041012290



Site

Name
WFD water body codes GB107041012290
WFD (national) typology Low, Small, Calcareous
WFD water body name R. Adur West
Pre-project morphology
Reference morphology
Desired post project morphology
Heavily modified water body No
National/international site designation
Local/regional site designations
Protected species present No
Invasive species present No
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

Reach length directly affected (m) 1000
1,000 m
1 km
100,000 cm
Project started 2013/08/08
Works started 2013/08/28
Works completed 2014/03/10
Project completed
Total cost category
Total cost (k€) £77k
"£" is not declared as a valid unit of measurement for this property.
Benefit to cost ratio
Funding sources Adur and Ouse WFD pilot catchment

Cost for project phases

Phase cost category cost exact (k€) Lead organisation Contact forename Contact surname
Investigation and design Environment Agency Gareth Williams
Stakeholder engagement and communication Ouse and Adur Rivers Trust Peter King
Works and works supervision Environment Agency Damon Block
Post-project management and maintenance Environment Agency Gareth Williams
Monitoring Environment Agency Gareth Williams

Supplementary funding information

£37k was spent on replacing a welfare unit that was damaged in winter flooding. Cost of project would have been £40k otherwise



Reasons for river restoration

Mitigation of a pressure Barriers to fish migration, Impoundments (not hydropower)
Hydromorphology
Biology Fish, Macrophytes
Physico-chemical Dissolved oxygen, Phosphates
Other reasons for the project


Measures

Structural measures
Bank/bed modifications Weir removal, Deculverting, Weir modification
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



Additional documents and videos


Additional links and references

Link Description

Supplementary Information

Edit Supplementary Information