Property:Lessons learnt
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R
Complimentary catchment walkover and remote sensing approaches are increasingly being used to understand the issues facing a failing catchment. The most challenging aspect of the River Worfe Restoration Project has been the survey logistics, whether on the ground or in the sky. In order to survey such a large area in a relatively short space of time, good preparation is vital. To ensure successful capture of all potential sources at the walkover stage, the entire catchment must be surveyed, which can be supported by the use of high resolution imagery. GIS software is used along with detailed maps at the preparation stage to ensure that all of the watercourses within the catchment are covered, before leaving the office. This approach enabled large areas to be covered systematically and efficiently. There were also logistical challenges at the sampling stage of the process, as not only was a large team required to sample 51 individual sites throughout the catchment in the space of a few hours, but also the weather conditions had to be favourable.
Gaining the trust of stakeholders and land owners to make changes was key. It took time to build trust with them and this only occurred when we had credible evidence, presented in an understandable way which demonstrated clear improvements. Understanding the business of arable farming in the Worfe catchment and the practical challenges was key to gaining the trust and respect of stakeholders. High resolution digital imagery from APEM’s aerial surveys of the entire Worfe catchment proved to be a very effective tool for engaging interest and understanding among stakeholders. We also spent time developing an ongoing relationship with stakeholders using a continuity of people in contact with them. +
C
Consideration of weather conditions during construction and possible delays
Consider public access once the new channel is completed
Need to monitor to analyse success in the future +
W
Correcting diffuse pollution is best achieved by working at the appropriate scale (farm by farm) in a catchment context. This delivers real and measurable benefits to WFD status as well as improving farm profitability.
Our revised SCIMAP is proving an invaluable tool in addressing problems of excessive overland flow and top soil loss to water. +
G
Cumulative benefits can be achieved through undertaking managed realignment schemes for habitat improvements which also form part of the local areas flood risk management strategy. +
Delivery of a large programme of works to deadline through COVID has been challenging but works came in within budget. Working in an urban environment is difficult and successful project delivery relies on engagement with the many stakeholders from the outset, particularly the local community. If new project officers are picking up the delivery of works and were not involved in the initial project development, then it is important that a through handover of work takes place. +
S
Despite all approvals and permissions being in place it was only when the contractors came to the site it was discovered that the only viable access to the site was over bridges with a limited weight capacity. this meant changing designs from six 3-metre square culverts to twelve half-size ones. All approvals and permissions then had to be re-sought against tight time limits, and with the weather deteriorating - the River Roeburn can rise extremely quickly. +
H
Discussions with partners can often identify opportunities for projects giving multiple benefits- continuous work with the IDB on similar restoration schemes. +
C
Early communication with permitting bodies and involvement of local communities is essential to deliver successful projects in a short timescale. +
L
Early negotiations with landowners are crucial! +
T
Eel tiles not strictly needed, as tide over-tops weir, so the aim was to allow eels to pass when the water level is below the weir crest. No formal monitoring but no issues, so far, apart from accumulating debris (August 2013). +
R
Ensure that all soil testing is undertaken months ahead of any scheduled groundwork. +
Equipment and materials are highly vulnerable to storms during construcion and their storage must account for 100 yr storm events. +
Expect the unexpected: Planting carried out in the winter of 2011 was followed by an exceptionally dry spring and summer, which placed the planted native species under considerable hydric stress and presented a real threat to their survival during the 1st year. However, surveys carried out in 2013 show that although the plants had a “rough start”, most of them have survived. The Mediterranean climate is characterised by notable annual and interannual variation in precipitation levels as a result of different phases of the North Atlantic Oscillation or NAO (Hughes et al., 2012; Trigo et al., 2004). Negative phases result in higher precipitation levels while positive phases result in higher temperatures and lower precipitation levels. Although these large scale climate patterns are beyond the control of any rehabilitation or NWRM project, they must be taken into account as part of the programme of measures.
Poor local stakeholder engagement: The implementation of the characterisation programme and subsequent rehabilitation programme along the river banks was initially met with much suspicion and some resistance by local farmers and land owners. The local farmers’ general perception was that land that was subject to intervention was being taken away from them, that risk of flooding would be increased, that project personnel were “trespassing” although, according to Decreto–Lei 54/2005 (República, 2005), the river banks and channel are in the public domain (although access has never been refused, local residents and land owners remain suspicious) and that the native plants planted along the intervention zones were of no commercial value and should be replaced by fruit trees, for example. Future actions to alert and educate locals to the value of lotic ecosystems, the presence of threatened species and NWRM must be more effective and interactive. +
Felled poplar trees provided locally won woody material but required substantial fixings to prevent their movement due to the porous and buoyant nature of the wood.
Cattle were observed to avoid the reject gravel ford crossing and walk across the existing softer bed material, causing erosion and mobilising silt. Formal cattle crossing designs and drinking points need fencing to prevent livestock from choosing their own routes. +
W
Firmly secure willow tubing; approx. 5% lost during spate event.
Willow whips to be planted from Autumn - early spring. Willow pots installed thereafter.
Waste to be protected by netting to prevent windblown pollution. +
B
Flow dynamics are important to the success of stream-parallel vegetation planting. In streams with a low discharge, fallen trees and leaves can cause backwater effects and obstruction. If a high flow velocity can be maintained, this will not tend to be a problem. If vegetation does not develop quickly enough, there is a risk of bank instability. +
F
Further elements were planned to be completed as part of the project but the landowner pulled out due to timing issues and weather, which may have affected his livery business. +
G
Future projects should incorporate time for delays such as flooding, water vole mitigation and other
potential difficulties.
Despite not being public land, improved communications with local residents would have made
progress much smoother. +
T
Good communication with the numerous landowners on the Test and Itchen is key to the success of this project. +
R
Has encouraged pride and ownership by raising awareness, educating and working with the local farmer. By using the site as a demonstration, there are opportunities for wider work to improve areas affected by rural diffuse pollution. Next steps are to promote the success of the project through social media. To support the use of the project site as a demonstration area, for example through farm walks. Support future projects in the area to deliver further outcomes. +