Campaigners against a planned sewage works made a stand of defiance by planting trees and shrubs on one of the sites earmarked for development.

Members of The Friends of Sheepcote Valley dug in 70 native species on the site in East Brighton, even though the land could be used by Southern Water for a sewage treatment plant.

The company is consulting people about eight possible sites for work following the rejection of a plant at Portobello, near Telscombe Cliffs, two years ago.

The sites are at Shoreham Harbour, Black Rock, Lower Sheepcote Valley, Upper Sheepcote Valley, Ovingdean South, Peacehaven East, Brookside Farm Tip and North Quay, Newhaven.

Two hundred people have signed a petition calling for Newhaven to be dropped as a potential site for a sewage works. The town is also the proposed home of a waste incinerator, to burn waste from Brighton and Hove and East Sussex.

South Portslade councillor Steve Collier is objecting to any proposal to establish a treatment works at Shoreham Harbour. He said it would lead to extra traffic.

On Saturday, volunteers from the Friends of Sheepcote Valley marched on to the site at Upper Sheepcote Valley.

Jane Hawkins, a member of the Friends group, said: "Every year we plant trees, tidy litter and plant wild flowers. If the sewage plant goes ahead, there will be a tourism impact on the area."

Sheepcote Valley is a popular site for walkers, bird watchers and animal lovers.

Ms Hawkins said: "We had already organised the tree planting and, despite the proposal, we went ahead with it."

The trees were hazel, hawthorn, spindleberries and wild roses.

The Friends are commissioning an ecological report on the site to present to Southern Water.

A spokeswoman for Southern Water said the company was working with the city council and a range of organisations to find a suitable site for the plant.

Damon Elliott, Southern Water project manager, said: "We have clear legal and environmental obligations to provide a modern wastewater treatment works to serve the 250,000 people of Brighton and Hove, Woodingdean, Ovingdean, Rottingdean, Saltdean, Telscombe Cliffs and Peacehaven."

Residents can still make comments about any of the proposals up until February 10.

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