Park lakes to be given pounds 600,000 clear-up: Nicholas Schoon reports on a scheme to rescue three ecological disasters

THE LAKES in many city parks are an ecological disaster area - murky water, floating rubbish, and muddy banks covered in goose excrement and feathers.

But a programme to beautify and clean three park lakes has been launched in London by Wandsworth Borough Council, which has been awarded pounds 600,000 by the European Commission for the purpose. Both the fish and the water are being changed in Battersea Park, but if the three-year programme is to succeed many of the geese will have to go, and the humans will have to change their behaviour.

The lake is suffering from eutrophication. It contains an excess of nutrients, which causes algae to multiply and makes the water look like pea soup. This plant food arrives in the form of excrement from fish, geese and other waterfowl, anglers' bait and large quantities of stale bread thrown in for the ducks.

Nutrient also comes from the murky waters of the nearby Thames, which is used to top up the lake. Conditions are such that on warm days oxygen levels can plummet, killing fish.

The council is drilling a borehole 400 feet into the chalk to reach nutrient-free water which will be used instead of the Thames. Bream and carp are being removed and replaced with tench and crucian carp. The substitute fish do not churn up the mud and nutrients on the lake bottom, nor do they prey so heavily on the microscopic animals which consume algae.

But the borough has not yet decided what to do about the Canada and Greylag geese whose heavy trampling, voracious grazing, copious defecation and rapid population growth are among the main causes of environmental damage. Wandsworth wanted to trap and shoot some of the geese during the last two summers, but dropped the plan because of public outrage.

It has asked the Wildfowl and Wetlands Trust to study the impacts of all the waterfowl species using the lake then work out what the best population level for each.

Meanwhile, Wandsworth will be planting prickly shrubs, including roses, around the banks to deter the geese. And it wants the public to stop throwing in bread.

(Photograph omitted)