Friends Of The Fish
31 July 2014
A Costain team working with Severn Trent Water (STW) has come up with a hi-tech way to protect fish and at the same time maintain a secure water supply.
Wyelands raw water intake on the River Wye near Lydbrook in the Forest of Dean, Gloucestershire, supplies up to 40Ml of water per day to STW customers. It is also a Special Area of Conservation inhabited by protected species such as lamprey and shad fish. Screens were already in place to protect the fish during water extraction but they did not prevent young shad and lamprey – which swim slower - from being drawn into the intake pumps.
If the intake works were to meet the new Conservation and Habitats Regulations 2010 that come into force in October this year, Costain had to find a way to protect the juvenile shad and lamprey, while maintaining a secure supply.
Working with STW colleagues, the Costain team carried out extensive research into screen technology before deciding on the US-manufactured Hydrolox screens. These screens feature a fine mesh that prevents small fish becoming drawn into the pump intake and a self-cleaning rotating mechanism that minimizes clogging. They have also been designed to fit within the existing intake structure so do not protrude into the river maintaining access for river users such as canoeists.
Following a detailed consultation with the Environment Agency, work on the new intake structure began in March. The site team faced challenges that included flooding and high levels of silt in the intake chambers but good planning ensured that the first pair of screens was installed on programme in May. A second pair is due to be fitted this month.
Said Chris Vice, Costain Delivery Manager: “This project is a significant milestone. It’s the first installation of a ‘fish screen’ on a direct river abstraction in STW, and also the first in the UK to use these screens. It will also inform future strategic investment programmes, as similar schemes could be needed at numerous sites in AMP6/7.”
Sad Buray, SWT Programme Manager, added: “All the legwork and homework has paid off with the first Hydrolox screens being installed and operational within the Company. The project team has met the challenge of working through a difficult winter and we are now experiencing interest from far and wide, with other water companies looking at our installation. This scheme is benefiting the environment and local people who use the river.”
Costain Communications Department