Agenda item

To update Committee members regarding the Winter works at the Brent Reservoir.

Ben Carroll (Project Manager, Canal & River Trust) provided an update to the Committee regarding the Winter works at the Brent Reservoir, which was commencing imminently and was expected to be completed by February 2024 to avoid bird nesting season and minimise impact on the Sites of Special Scientific Interest (SSSI). Members were advised that the Canal & River Trust had been given permission for carry out the works by Natural England and were legally required to carry out the works in the interest of safety, with planned work including painting and repairing the bell tower, inspecting sluice’s, general inspections of the Reservoir dam and necessary repair works.

In order to complete the required work, it was explained that the Reservoir would have to be fully dewatered, with the Committee noting that the required gear and equipment was currently being mobilised and water quality monitoring had begun in preparation for the dewatering. Ben Carroll also detailed that the Canal & River Trust expected their application for a Flood Risk Activities Permit to be approved in the near future, meaning that the drawdown of the Reservoir would likely commence in the week beginning 27 November 2023.

In discussing next steps, Ben Carroll informed members that the dewatering process would take approximately four to six weeks and would involve a fish health check and rescue, with native fish relocated elsewhere in the water network. In addition, silt mitigations would be replaced where necessary and, once the Reservoir had been fully dewatered, the aforementioned inspections and works could take place which would continue over weekends and the Christmas period to progress the programme as fast as possible.

To conclude the update, Ben Carroll stated that the Reservoir was expected to be refilled by the end of February 2024 and reassured the Committee that regular dialogue was ongoing between the Canal & River Trust and Natural England. Furthermore, members were advised that the silt on the bed of the Reservoir was very dangerous and therefore the Committee was warned to not enter the Reservoir, to warn others of the dangers and to call 999 if they saw anyone going on the silt or were stuck. Lastly, the Committee noted that a virtual webinar was being held by the Canal & River Trust on 30 November which would provide a much deeper overview of the planned Winter works. Members were encouraged to register for the webinar and submit questions in advance.

Having thanked Ben Carroll for the update, the Chair invited comments and contributions from Committee members, with questions and responses summarised below:

•         In response to a question relating to the silt measures, members heard that the silt measures were gabion baskets which stopped silt flowing downstream which were a temporary measure and would be removed before the reservoir was refilled. Moreover, it was explained that the gabion baskets would be arranged in a triangle shape which would form a stable base and therefore would not require stakes. However, retrospective works could be carried out in the case of unforeseen problems.

•         The Committee was informed that the Canal & River Trust was reviewing invasive species as part of the Winter works and that there was a process in place to remove any identified species humanely and to not accidentally spread invasive species through the transportation of equipment.

•         Regarding rubbish collections over the Winter, it was detailed that the Canal & River Trust had organised volunteer collection days around the perimeter of the Reservoir and had hired a contractor to support in the rubbish collection. However, the true scale of the rubbish would not be known until the Reservoir had been fully dewatered and members were advised that large amounts of rubbish came from upstream which was difficult to control.

•         In response to a query concerning the impact of microplastics from rubbish that coated mudflats and marshes, the Committee noted that experts at the webinar on 30 November could provide detailed responses to these complex concerns.

•         Given that much of the wildlife in the Welsh Harp relied on the fish in the Reservoir for survival, the Committee questioned how the Canal & River Trust would ensure that enough fish stock was returned to the Reservoir in time for the breeding season in March. In response, members were advised that there were ongoing conversations between the Canal & River Trust and Natural England regarding when and how fish would be restocked. The Committee was reassured that comments and concerns would be passed onto experts and in-depth responses would be given at the webinar on 30 November.

As no further issues were raised, the Committee AGREED to note the update.