Updates
Video Update
The main contractor for The Cockshut Stream Restoration Project, Ebsford Environmental, has produced a video that gives an overview on the project and an update on its progress.
Breaching the banks
On the 9th of august 20223 the banks for the Cockshut stream were breached allowing the water to flow into the newly created wetland. We expect it will take a number of days for the water to find its natural level. The water levels will need a low level of management in the future to ensure the right amounts of water are heading down the stream and down the Celery Sewer.
Stakeholder site visit
On the 11th of July, we were pleased to host site visits for Councillors, landowners, partners, stakeholders, funders and colleagues to learn about the project and see the progress on site.
The project has only been possible through a strong collaboration between Lewes District Council, Ouse Adur Rivers Trust and The Railwayland Wildlife Trust.
Thanks to Emily and her colleagues from Ebsford Environmental and Peter from Ouse Adur Rivers Trust for facilitating the visit and offering insights into the project.
School trip
On Monday 10th July we hosted a visit of 90 children from Years 1 and 2 at Southover Primary School. The students got involved in several activities and had a special site visit to look at the engineering works and the types of machinery the contractors are using on site.
We were impressed very impressed by the children’s existing knowledge of the environment and by the questions they asked.
Big thanks to our contractors Ebsford for allowing them onsite, providing activities and sending them off with some goodies at the end of the day, and to the staff and teachers at Southover School for coordinating the visit.
Works has commenced
Construction works commenced on the 5th of June and are progressing well, helped by the fantastic sunny weather.
The contractors first job was to strip off the existing vegetation and stockpile the material for use on site later. Next they start cutting out the main channel that will allow the stream to meander through the site once its completed.
Construction contractor
We are pleased to announce that Ebsford Environmental will be constructing our wetland and associated works. Ebsford have many years of experience in transforming open spaces by restoring and enhancing aquatic features, integrating flood alleviation features, creating more habitat for biodiversity, introducing new footpaths and accessibility features that bring the public closer to nature.
Archaeology
During March 2023 an archaeological evaluation and geoarchaeological investigation were undertaken in advance of restoration work to re-route the Cockshut Stream and create a new wetland habitat by Chris Butler Archaeological Services Limited. Significant waterlogging was problematic for the duration of the evaluation.
A total of fourteen trenches, thirty metres in length, were machine excavated to a maximum depth of one metre. All trenches recorded similar stratigraphic profiles consisting of a topsoil, subsoil, gleyed alluvial silt and gleyed alluvial silt with iron oxidisation. A very small assemblage of Late Post-Medieval ceramic building material (CBM), pottery and a clay pipe were recovered from the topsoil and subsoil. Although numerous trenches recorded modern, possibly naturally eroded water channels, only two features of archaeological interest were revealed. Trench two recorded a ditch of unknown date (likely Late Post-Medieval), which was not obvious in plan or from Lidar data. Trenches ten and eleven recorded a section through a large ditch running north to south containing numerous fills and modern (likely 20th Century) brick, tile and scaffold poles. No further features of archaeological interest were recorded.
Geoarchaeological investigations in the form of hand augering recorded peat deposits overlain by alluvial deposits across the site. Two cores (to a depth of c.8m) through the alluvial silts, peat deposits and river gravels below, down to the weathered chalk periglacial deposits were retrieved for further geoarchaeological/environmental analyses.
The Plan
Driven by the Ouse and Adur Rivers Trust’s (OART) vision to develop a rich and diverse environment which supports a range of wildlife species and inspires individuals and communities to engage with and protect their local river systems OART and LDC has contracted cbec eco-engineering to develop a detailed design option for the restoration section, taking into consideration the local constraints of the site, such as the downstream tie in point, existing services, and the requirement to not increase flood risk to the adjacent properties.
Historical management of the land surrounding The Cockshut required the construction of the channel to help with management of drainage of the surrounding marsh land, diverting flows from upstream and capturing surface water runoff from the land between Lewes town and the channel, in the area that is now the playing fields. Managing flows and draining the marsh land allowed the development of the land for agricultural purposes.
OART and Lewes District Council (LDC, principal land owner for the site) are seeking to implement restoration measures which help improve morphological and ecological conditions in the channel and the surrounding land area, recognising that The Cockshut is an artificial construction but that drainage of the site is still required. To achieve this goal desk and field-based assessments were undertaken, then initial and detailed design development for the site and the hydraulic modelling results comparing flood risk for existing and design conditions Engineering drawings for the final design were then developed.
A Little History
The River Ouse has a long, vibrant, well researched and acknowledged history as a working waterway carrying goods to and from Lewes.
Much less known about is the Cockshut, the first major feeder stream inland from the coast on the west bank of the Ouse. It also was an important working waterway particularly during the early years of Lewes priory. It formed the southern boundary of the monastic precinct and much of the building stone brought in for the priory from the Isle of Wight and from Normandy (Quarr and Caen respectively) between about 1080 and the mid- to late-12th century was very probably offloaded directly into the precinct from the Cockshut.
A branch stream of the Cockshut, perhaps an engineered diversion from the main stream and nowadays sometimes referred to as the Upper Cockshut, ran through the service areas of the priory supplying a watermill, the monastic kitchen and maltings, fish ponds, and the reredorter (toilet block).
Centuries later, in the 1830s, the Cockshut was used to supply water for the first piped-water system to serve Lewes from the reservoir head opposite the Black Horse in Western Road.
John Bleach
We Went For A Walk…
The idea for the Cockshut Stream Restoration Project came about after representatives from Lewes District Council, the Ouse and Adur Rivers Trust, the South Downs National Park Authority and the Environment Agency went for walk to look at opportunities to improve the Chalk streams that run through Lewes.
The two streams, namely the Winterbourne and the Cockshut streams, have been moved and canalised over time providing poor aquatic habitat.
The land behind the Stanley Turner Ground was identified as having potential to create a wetland area - and so it began!