Air power was deployed to bring a new piece of mixing equipment – the first of its type in the South East – to the middle of a reservoir.
The two pieces of equipment, each weighing a ton, were lifted into position by helicopter at Southern Water’s Weir Wood reservoir near East Grinstead.
Southern Water Project Manager Oliver Ryan said: “The reservoir experiences algal blooms during the summer months, which can impact on the effectiveness of equipment used for the water treatment process.
“Southern Water selected a replacement mixing system, called Resmix, to provide significantly increased mixing of the reservoir to control algae growth.
“The mixer comprises two, 4m diameter paddle mixers, which spin at a low speed and slowly force the water from the top of the reservoir downwards. Over a period of weeks this movement sets up a circulation of the water and creates a uniform temperature through the body of the reservoir. The mixing reduces the preferred conditions for algae growth, thereby reducing the amount of algae in the reservoir.”
Previously the algae was cleared using a ‘bubble curtain’ – a pipe with holes that has air pumped through it to create a wall, or indeed curtain, of small bubbles. This disrupts the algae and stops it from settling.
However, the new piece of mixing equipment has been installed as part of the company’s multi-million-pound investment to improve the site’s reliability and ensure a consistent output of high-quality water.
The installation was carried out by one of Southern Water’s construction partners, CMDP.
The Resmix floats on the surface of the water and is anchored to the bottom of the water supply reservoir.
The equipment has to be in the deepest part of the reservoir and the use of the helicopter was the most efficient method to get it into position.
-Source Southern Water-