River of Life ll FAQs
The contractors will be on site from May – October 2021. Local signage will indicate the periods when they will be working on each of the areas to be excavated, with outline schedule expected to be:
Church Farm – late May to mid August; Clifton Meadow – late May to early August; Little Wittenham Wood – late June to late July; Overy Mead – late July to end August.
In all four areas you will see excavators forming the wetland features. At Clifton Meadow and Church Farm, dumper trucks will take excavated soil to a nearby arable field to be spread and ploughed. Working hours will be Monday-Saturday, restricted in line with planning conditions. In Little Wittenham Wood you will see machinery excavating the ponds (excavated soil will be retained and used within the wood).
There will be some short term impacts on public access. Public safety is paramount and given the nature of the heavy plant used in forming the new wetland features, it will be important to keep members of the public away from the works. At Clifton Meadow and Church Farm, the Thames Path will remain open but with temporary short distance diversions while the backwater channels are being excavated. There will be a diversion of the route from Northfield Lane to the Thames Path, which will take walkers through the adjacent field in order to protect them from site traffic. At Overy Mead the two backwater locations will be restricted for safety reasons, but access to the Thames Path will be maintained. In Little Wittenham Wood the bridleway through the woodland will remain open, but with no access into the area where heavy machinery will be working.
In the interests of road safety, we will keep road users informed and manage traffic as required by Oxfordshire County Council Highways. Road use will largely be restricted to arrival/departure of machinery and labour to the site; heavier vehicles will only be transporting spoil via public roads from Overy Mead (the smallest of the sites).
Yes, there will not be any restrictions for river users on the River Thame or Thames. While the backwater channels are being connected to the river, excavators will be working close to the river banks. Warning signs will alert river users to the works.
The grazed meadows at Clifton Meadow and Church Farm contain areas of wildflowers and wetland plants. Where appropriate, the topsoil, which contains the seedbank, will be retained and spread back over the banks and margins of the newly created ponds and backwaters. This will help quickly establish plant communities. In order to make way for the new ponds in Little Wittenham Wood have felled approximately 150 trees. The areas where the work will take place, however, are predominantly secondary woodland planted relatively recently and as such support a lower abundance and diversity of species than other parts of the wood. Wildlife surveys have taken place to make sure that we have a complete understanding of species that use the area, allowing us to plan the work accordingly to avoid any potential damage. At Overy Mead, mature willow trees were pollarded during winter 2020-21 to enable access during excavation.
We will work under licence from Natural England and will minimise any potential impacts on great crested newts during excavation; Little Wittenham Wood is a designated site so special permission will be required to create the ponds. We’ll carry out tree work during the winter to avoid impacting nesting birds. Effects on bats will be avoided through careful design informed by surveys, alongside the appropriate method and timing of work.
No trees are expected to be removed at Clifton Meadows or Church Farm. Approximately 150 trees within Little Wittenham Wood require removal in order to excavate the ponds for great crested newts, as described above. The ponds have been located in areas that don’t contain veteran trees or ancient woodland
We will be avoiding the root protection areas of retained trees to minimise impact. Where this is not possible (for example due to a pinch point for access) temporary trackways will be used to spread the weight of vehicles. The design at Overy Mead has been adapted to allow the mature willows within the northern backwater to be retained. Willows are water loving trees and thrive on the riverbanks. Willows are resilient to root impacts and excavating near the trees will be carefully managed in agreement with the council’s Tree Officer.
Extensive archaeological trial trenches were explored in June 2019 at Church Farm, Clifton Meadow and Overy Mead. One significant find, recorded at Clifton Meadow, was a piece of worked wood. An archaeologist, from Dig Ventures, will be present and undertaking an archaeological watching brief during excavation of specific ponds and backwaters.
For the works a Flood Risk Activity Permit will be required from the Environment Agency, the requirements of which would protect the floodplain during the excavation of the backwaters and ponds. Soil excavated from the newly created ponds and backwater channels in the floodplain will be spread and ploughed into neighbouring farmland. The Environment Agency has stated that the excavated soil can only be spread outside of the flood zone – the area that will flood once in 100 years, plus a 35% allowance for climate change. The aim of this restriction is to avoid reducing flood storage capacity elsewhere. In the long term, the new ponds and backwater channels will create new flood water storage in the floodplain of the River Thames and Thame.
Small bunds will be used on the river side of the culverts during construction of the backwaters at Clifton Meadow. These will be removed at the end of construction, once the culverts are finished and the backwaters have been dug. Silt traps will also be used to minimise the chances of sediment getting into the river.