The botanists, landscape artists and water engineers who have transformed four disused Victorian reservoirs into a wetland reserve are "the Christopher Wrens of habitat creation", says Malcolm Whitehead, head of education and visitor services at the new Wetland Centre in south-west London.
Opened in May this year, the 105-acre site in Barnes is a mosaic of lagoons, lakes, ponds and pools. It has been five years in the making and is the biggest natural wildlife development in any capital city. As you wander through the seemingly endless marshes and reed beds, it is hard to believe you are just a few miles from Piccadilly Circus.
It was Sir Peter Scott, founder of the World Wide Fund for Nature and son of Scott of the Antarctic, who first dreamed of a wetland centre in London "where wildlife and people could meet for the benefit of both". He founded the Wildfowl and Wetland Trust, which runs the centre, but died 11 years before his vision could be fulfilled. A striking bronze statue of him in wading boots stands on a boulder in shallow water by the entrance to the visitor centre.
The Thames has always been popular with migrant birds: more than 10,000 wildfowl make their winter home in its marshes and mud flats and the Barnes reservoirs were a site of special scientific interest long before they were identified as the location for a wetland centre.
The reservoirs were decommissioned in 1994. When Berkeley Homes bought the north side of the site for a riverside housing development, as a condition of being allowed to build there the company agreed to use part of its profits from selling houses to fund the pound;16 million nature reserve.
"The entire project is about creative learning and what we've tried to do is make the whole site a classroom," says Mr Whitehead. "It's a form of social activism. If people are made aware of the importance of these habitats and our connection with them, they will feel inspired to become actively involved in protecting them."
The centre has already attracted 130 species of wild birds, including the relatively rare lapwing and little-ringed plover. The wild reserve covers more than 70 of the 105 acres. "It's a five-star hotel for birds, so they are very pleased to stop here," says Mr Whitehead. Permanent residents include herons, kingfishers, coots, grebe, pied wagtails, mute swans, ducks and geese.
The secret of the attraction for birds is the wide variety of controlled habitats. For example, the grazing marsh is flooded in winter to suit dabbling ducks and wigeons, and drained in spring to provide nesting sites for wading birds. There is also a wader scrape, where water levels are lowered in spring and summer to expose large areas of rih mud, which are the perfect feeding grounds for redshank and other probing waders. Other habitats include the main lake, the wildside area of ponds and pools, reedbeds, a reservoir lagoon and a sheltered lagoon. All are seasonally managed to satisfy the requirements of winter and summer feathered visitors.
The visitor centre includes a glass observatory, which gives bird "arrival" and "departure" information, a discovery centre, an art gallery and a lecture theatre, plus a restaurant, cafe and shop. Closed circuit television relays live images from the wilderness areas of the reserve and touch-screen computers offer children the chance to learn more about the importance of the wetlands and the wildlife they attract.
At the world wetlands area, you can walk through 14 different habitats ranging from an Australian billabong to Siberian tundra and see wildfowl from each. In the pond zone, children can go dipping and examine their haul under a magnifying glass, and there are several lakeside wooden "hides" and binoculars to get a closer look at the birds.
"One of the best things about this place is that it gives London children a chance to see what the countryside is like," says maths teacher Michael Sinclair, who has brought a group of Year 5 pupils from Latymer school in Hammersmith, west London.
The children have been pond-dipping and are intently inspecting the water beetles, tadpoles, damsel fly nymphs and greater water boatmen darting about in their observation trays. Support materials from the education department help them to identify the creatures and there is much animated discussion.
"Learning from real life makes a welcome change from learning from books and I think an exercise like this - matching things and finding out about them - helps the children to learn to listen to each other," says Mr Sinclair.
"They know the riverbank well, because our school is very near it, but they probably don't think much about what goes on in the undergrowth. Hopefully, after this they will."
The Wetland Centre, Queen Elizabeth's Walk, Barnes, London SW13 9WT. Tel: 020 8409 4400; email: firstname.lastname@example.org www.wwt.org.uk Open daily except Christmas Day. British summer time 9.30am-6pm; winter 9.30am-5pm.
Pre-booked school parties pound;3.25 pupils, pound;5.25 adults. Teachers and helpers free 1:6 with reception to Year 2 children, 1:10 with older children.
Learning sessions at the Wetland The education programme Wise up to WEBS, which is about water, ecology, biodiversity and sustainability, is aimed at KS1-4, covering science, English, maths, geography, PSHE and citizenship.
There are Discovery programmes for pre-school and special needs pupils. The centre also runs tertiary programmes.
A teacher's pack Ducking and Diving for KS2-3, costs pound;5 plus pound;1.50 pamp;p. More packs are planned.