Property:Project summary
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This is a property of type Text.
B
Notch weir to improve fish passage. Delivery by internal EA operatives. This is an ornamental weir with three low-head stages. Presents a barrier to fish movement during normal river flows. +
H
Notch weir, and possible fish pass. De-silting, flow deflectors, cunker structures, wetland cut and fill, coir rolls; narrowing of river. Overwide section of river with concrete banks +
E
Notching of weir and /or attachment of brushes for eel migration. Tidal Creek of the wandle has a number of structures causing a barrier to fish passage and holding back water causing a decline in diversity. This will create an easy to do project and make the river more accessible. +
B
Objectives:<br>Improve water flow and quality; bank naturalisation and enhanced provisions for biodiversity; increased leisure, recreational and educational opportunities.<br>
Methods:<br>Bank re-profiling using coir banks and new planting; removal of siltation to recreate single rather than two islands to enhance areas used extensively by wildlife, remove silt from lake to improve water quality and allow for the introduction of water safety training in schools, removal of toeboards, reedbed creation.<br>
09.11.09 Next steps - approval in principle required from all those associated with proposals, detailed survey to define precise form and extent of the various parts, define programme for works execution, obtain funding. Possible constraints - quality of silt to be removed if necessary from site rather than to use in association with bank re-profiling and recreation of larger single island +
R
Obstructions to fish migration on the Dee:
Since 2007, the Dee DSFB and Trust have eased or removed 27 manmade obstructions to fish migration from the river Dee's tributaries.
'''the aim is simple: To allow fish to gain access to their natural spawning grounds.'''
These manmade obstructions include weirs, bridges, vehicle fords and culverts. Some are completely impassable to fish, others are impassable in low flows; the latter can delay migration and have a knock-on effect of making fish more vulnerable to predators and stress.
In 2007 we assessed all the known manmade obstructions to prioritise them for easement or removal. For example, removing an obstruction that is on a tributary with poor habitat for salmon, or that is located close to the headwater source, will offer a lot less potential for increasing fish production than removing an obstruction that is low down on a prime-quality tributary.
The physical work of tackling the obstructions is often supported by obtaining external funding, particularly from SEPA's Water Environment Fund and from the EU LIFE fund. The physical works are completed by contractors or in many cases by our staff.
In 2014, the largest manmade obstruction was eased by installing a fish pass to the face of the Culter dam and two weirs further upstream in the Culter tributary were eased +
F
Of the variety of existing fishways, in this particular case the chosen option was the
installation of a pool fishpass, the most used kind of fishways.
The advantages of this kind of devices are:
- Little selective. Most fish species will be able to use it effectively.
- It admits wide ranges of flows.
- It presents an optimum behavior against changes of the water level.
The disadvantages of this kind of devices are:
- Plenty of space is required for its installation.
- It needs more maintenance because it can become blocked.
- The price is higher than other fish pass options.
In this case, due to the location of the dam it was decided to build the fishway with a
curve of 180 degrees.
Among the alternatives of permeabilization, weir removal was not proposed since the
obstacle is in use and it serves to generate hydroelectric energy. An agreement was
reached with the owner in order to make a fishway that at least guarantees the
circulation of a constant flow downstream the weir.
With this permeabilization it is possible to recover the connectivity between this
section and the headwaters of the Guadiela River. However, the presence 3 km
downstream of the Los Tilos dam (more than 6m high) prevents this recovery from
being complete. It is therefore required to permeabilize this obstacle in order to
achieve a more complete reconnection. +
S
Off-channel fry bays, flow variation, woody structure introduction +
W
On 2nd February 2013, a slurry incident along the Wellow Brook in Somerset caused a major fish kill and was reported by the Environment Agency as one of the worst pollution events in many years. The Wellow Brook has been designated a score of ‘Poor’ and the Cam Brook ‘Moderate’ in 2016 under the European Water Framework Directive (WFD).
From a small donation of £5,000 for the Enforcement Undertaking, BART has raised over £100,000 towards the project to date. BART has delivered the following:
Habitat assessments along the length of the Wellow and much of the Cam.
Mapped all barriers along the Wellow.
The removal of three boulder weirs that were impounding flows and smothering potential spawning substrate with sediment throughout ~8km reach.
Removal of 1 small weir and re-profiling of 2 boulder weirs in the lower Cam Brook
Pre-feasibility assessments for a large weir at the confluence of the Wellow Brook
Pre-feasibility assessments for a ford which is presenting a barrier to fish on the Wellow Brook
SNIFFER fish passage assessments on 3 weirs in the urban section of the Wellow
~20km of habitat improvements with LWD and coppicing
A successful partnership project with Midsomer Norton Town Council to improve a section of river which has now been turned into a Local Nature Reserve.
3 Riverfly monitors monitoring the Wellow on a monthly basis as well as several more BART Beacons
A pre-barrier removal electrofishing survey which we will aim to follow up with a further survey shortly to assess ongoing improvements in future years
The creation of a Friends of river group with Shoscombe Parish Council
Riparian fencing and buffer strip creation on the Cam Brook and Norton Brook
The installation of formalised cattle drinking areas to reduce poaching on the Cam Brook and Norton Brook
A programme of coppicing and LWD along a 2km reach of the Cam Brook
Strategic discussions with the Environment Agency about removing a redundant asset as a result of opening up the river to this point via BART’s work to date.
Engagement with over 250 local people, through river sessions, ‘Yellowfish’ antipollution projects and public talks.
Several litter picks, including a recent one where over 200 plastic bottles were removed and turned into a plastic fish which has attended many local events
A Challenges and Opportunities report outlining key issues and potential work-packages throughout the Wellow & Cam Brooks.
S
On the River Senni (which is a tributary of the River Usk), Powys County Council with support from the Four Rivers for LIFE Project replaced an old pipe bridge with a clear span bridge. The old bridge was prone to blocking and was a barrier to fish and natural sediment movement. Green bank protection measures such as tree root wads, brash and willow stakes were used to prevent erosion around the structure in this high energy environment. +
P
On the river Corrèze, near the town of Tulle, five weirs interrupted the ecological continuity and limited the recreational use of the river, since the passage of kayaks was hindered. The largest, 3 m high, was identified as the most problematic. This weir was partially removed (levelled), maintaining its basement and a residual 30 cm drop, to ensure the stability of the longitudinal profile, but at the same time allowing the passage of fish and canoes.
Downstream of the weir, a 40 m long riprap ramp was realized, to avoid erosion. The ramp was built with a curved shape to concentrate flows and facilitate the passage of fish fauna at low water level conditions.
Along 600 m upstream the weir and on the internal side of the meander, the banks were protected with the installation of a vegetated geotextile. On the external side of the meander blockstone deflecting groynes were positioned, alternated with layers of coarse gravel extracted from the riverbed, in order to protect the retaining wall of the existing road.
Monitoring of hydromorphology, vegetation and fish fauna has been foreseen. +
R
On-line lake improvements and bank works. Blacks Brook runs through Raphael Park. It becomes an on-line pond which comprises concrete banks. The river and pond are largely devoid of environmental features with footpaths and hard standing right to bank top. Any vegetation that did exist has been destroyed by Canada Geese. +
W
Once the project is complete, approximately 2.5km of the River Wensum flowing through Pensthorpe will have restored ecological and hydrological functionality and provide habitats for a range of key chalk river species such as brown trout, white-clawed crayfish, Desmoulin’s whorl snail and water crowfoot. In addition to this, the adjoining floodplain will have significantly enhanced connectivity to the river and diffuse pollution from both Fakenham and adjoining agricultural land will have been mitigated. +
V
One of the barriers catchment partnerships face is understanding what action needs to be taken to improve rivers to good status. River Basin Management Plans provide information
on why rivers are failing to achieve good and generic actions, but are not specific around how to can close the ‘gap to good’.
Valley Brook in Crewe is a small urban watercourse. It is failing water quality standards because of upstream inputs of nutrients, mainly from sewage works and agriculture, and because it has been
constrained and altered as Crewe has developed. United Utilities have committed to upstream improvements at Audley sewage treatment works which will lead to significant improvements in water
quality before 2024.
Next Steps
Feasibility and design work has been commenced on the river restoration and partners are developing a business case. Valley Brook partnership members have started discussions with land owners to look at delivering more mitigation measures, along with identifying suitable funding streams. +
A
Austria Upper Mur - River widening Lässer Au (LIFE+ (LIFE+ 08 NAT A 614) Inner-Alpine river basin management – Upper River Mur - murerleben II 2010-2015) +
One of the goals of the Upper Mur is the recovery of habitats, which went lost to a large extent through the regulation of the Mur. The widening Lässer Au therefore aims - together with the measures implemented in Weyern and Apfelberg - at providing a contiguous, rich structured water course and alluvial areas.
For the dynamic development of the river Mur, the existing bank protection has been removed on the left bank and a 900 meter long structured side-arm with two inflow areas has been created. In addition, amphibian basins were built with a total area of more than 4,000 m² and 8 ha of alluvial forest areas have been secured or re-initiated.
In the Lässer Au riparian zones with deadwood from rhizomes were designed. Deadwood in the water not only increases the biodiversity of small animals in the water, but also is of use for the fish, as they discover valuable habitats between the branches.
Through the implementation of new measures in the context of the first LIFE project large contiguous water courses and alluvial forests are created or preserved. Especially species, which require different living conditions depending on the season or their development, benefit from the newly created habitats. +
R
One of the main issues raised by the local community was that there was very little access to the river.
In partnership with local landowner Eddie Anderson Norfolk Rivers Trust have established a 13 acre nature reserve which offers local residents the opportunity to visit and help conserve this beautiful river. Since March 2014 we have been very productive and worked alongside a team of enthusiastic volunteers to carry out a variety of tasks ranging from removing invasive species to creating bird boxes. +
P
One of the most heavily modified and constrained sections of river corridor in the UK. Failing for WFD (Fish, Hydromorphology and Invertebrates)
* In it’s current condition presents a flood risk downstream
* Has no natural connectivity with Clayton Vale and Philips Parks
* No formal access for public
* No recreational activities undertaken
'''Feasibility'''
*Completed flood risk assessment
*Completed a full contaminated land assessment
*Engaged with the community via the River Restoration in Schools project
*Surrounding Ecology and Biodiversity surveys complete
*Community and partner engagement
*Partnerships secured
*Full designs complete
*Monitoring programme established +
R
Opening up of the creek to the Thames - removal or modification to the tidal sluice. The river is currently impounded.<br>Poor water quality downstream of Riverside STWs.<br>Fish and eel movement is almost totally restricted.<br>Removal would provide the opportunity to creation of BAP habitat; reed, inter-tidal.<br>The River Lee has been impounded, this could offer alternative migratory routes for fish.<br>Massive biodiversity gains can be made by removal of one structure.<be>
Possible constraints included, Potentially very costly, FRM risks need to be fully addressed, Conflicting aims from user groups, Currently a waste management facility is present on site, at mouth of the creek. +
L
Options for removal or modification/lowering to increase fish passage and create intertidal habitat upstream. Lewisham College half tide weirs at top of Deptford Creek. Concrete raised channel above, intertidal mudflat of creek below. Barrier to fish migration at low states of tide and overtops at high water.<br>
Need to confirm funding to progress project +
H
Originally the funding for this project was meant to build a fish pass at Sprotbrough weir in Doncaster but British Waterways (BW), the owners of the weir, had a last minute change of heart and announced that they were planning to install a hydro scheme on the weir. They were to use Small Hydro(SH) to build it. . The change required BW to install a fishpass as part of the construction. Despite the fact that a fishpass had already been designed it was essential that a new design was undertaken covering the hydro scheme and fishpass in order to provide an effective solution. As the construction had now become part of a commercial operation it was felt inappropriate for public money to be used. After consultation with ART and the EA the Trust withdrew its' offer of funding. The EA similarly withdrew its' funding from the project. However, approval was received from DEFRA, the EA and The Rivers Trust for the project funding to be transferred from the Sprotborough Weir project to the Hadfields Weir project.
Historically the rivers of South Yorkshire were heavily utilised for the requirements of industries such as coal and steel. The obstructions left over from these industrial days are now causing obstacles to the free passage for many species of fish thus suppressing the recovery of fish populations.
Hadfield Weir on the River Don is one of the major obstacles on the river. It is highly visible as it is located outside a very busy shopping centre that has a footfall of 30 million people; there is a busy cycle and footpath on the riverside which is part of the Five Weirs Walk that runs from the city centre.
Don Catchment Rivers Trust, almost entirely through the work of volunteers, managed to secure a not inconsiderable amount of money from the Defra River Improvement Fund to enable a multi-species fish and eel pass to be built. This will help to restore river connectivity for fish and eels in the River Don, allowing fish to move between habitats above and below the weir, essential if it is to be fully exploited for feeding, rearing and breeding.
This project is part of a wider scheme on the Don to allow fish passage and encourage the return of salmon. This iconic species is the ultimate indicator of clean, healthy rivers and would have economic as well as environmental impacts for the city of Sheffield
R
Originally,the solution sought by the commune was to carry
out hydraulic works. The engineering consultant in
charge of the project, after consultation with state
departments, was asked to give a more “ecological”
and hydromorphological” dimension to the project.
In addition to the initial solution to rehabilitate
the reach by reinforcing the banks, returning the
watercourse to the bottom of the valley was also
proposed, as the original bed of the Fontenelle was still
identifiable. At the end of the study and examining
the different scenarios and after consultation with the
commune and residents, it appeared that returning the
Fontenelle to its original bed was the least expensive,
most hydraulically viable (overtopping of the river in
the event of flooding into neighbouring meadows
and marshes) and the most hydrobiologically and
hydromorphologically beneficial solution.
The river was returned to its original bed for a
1,200 m stretch and the banks gently sloped. The
weir on the reach was removed.
Water was returned to the bed in September 2010.
In spring 2011, helophyte, shrubs and trees were
planted and fences and animal feeders set up along
the restored site to protect against trampling by
cattle. Foot bridges were also built. A grassy ditch
now replaces the perched reach to collect stormwater.
Mechanical equipment used on the project site
all used biodegradable hydraulic oils which, in the
case of an incident, avoided contamination of the
aquatic environment.
Fish from the perched reach were caught preventively
before works started. +