Living roof lends treatment works a natural beauty

A living grass roof - the biggest of its kind in the United Kingdom and one of the largest in Europe - has been laid on top of a new waste water treatment works in southern England.

Measuring 18,000 square metres - almost the size of five football pitches - the grass-covered roof has been designed to blend in with the natural beauty of the South Downs that surround the location at Peacehaven in Sussex.

The thousands of turf sections used to cover the roof area were formed from grass, grown from a special mix of downland grass seed that was kept under cultivation for 15 months in Cambridgeshire.

It will be a defining feature of the regional water utility company Southern Water’s 300 million pounds environmental improvement scheme that will bring cleaner seas to the Sussex coastal area of southern England.

Once completed, the treatment works will be able to process the 95 million litres a day of waste water generated by residents of Brighton and Hove and surrounding areas, including Peacehaven, Saltdean and Roedean, to the latest European Union standards.

Taking almost four years to construct and following nine years in the planning, the project will be completed by March 2013 and includes underground tunnelling, the construction of a sea outfall, two new pumping stations and construction on 11 sites.

The area to the south of the works is to be turned into a park - with local people deciding its use - and may contain a cricket pitch.

Southern Water programme manager Ben Green said: “The roof, designed to fit in with the local landscape will be living - it responds, it adapts, it evolves with the landscape.”

The grass roof and its harmony with the surrounding countryside reflects Southern Water’s environmental management scheme relating to sites of special interest and outstanding natural beauty.

The company has an overall investment plan for 2010-15, under which 1.8 billion pounds, at current prices, is being spent on a programme of environmental and service improvements across the region.

During 2010 there was a general capital investment of more than 400m pounds into improving its water and waste water works, pumping stations, sewers and water mains. Programmes included the creation of a reservoir in west Sussex and the re-laying of 56 kilometres of water mains and 11.5 km of sewers.

The company is also designing a surface water-separation scheme that will take place in various locations between 2012 and 2015, and will reduce the risk of sewer flooding in towns such as Portsmouth.

Other large work programmes under way include a 1.3 million pounds flood-reduction scheme in Dover to cut the risk of pipes overloading during storms.

As part of its long-term plans to secure water resources for the future, Southern Water has launched a metering programme and is installing 500,000 meters in customers’ homes.

By 2015 up to 92 per cent of customers will have a meter, a target in line with other European nations. The programme is expected to lead to savings of 17.6m litres of water each day.