The new breed of conservationists teamed up with environmentalists, architects, town planners and other professionals to demand more democracy in town planning mechanisms and procedures. Only genuine public participation, they asserted, could protect Hong Kong's identity and cultural heritage in the face of a development model that disregarded sustainability.

The path to their first major victory began at the turn of the millennium - a three-year struggle to save a piece of wetland in Sheung Shui. Long Valley, at 2.5 hectares, is Hong Kong's second-largest wetland. About half as big again as Victoria Park, the valley is home to 210 species of birds, half of the known species in Hong Kong. It also is home to 97 types of butterfly and nine species of reptile.

The KCRC had planned to bisect the wetland to build the Lok Ma Chau spur line. But conservationists put up determined resistance, turning their battle with the railway into a city-wide campaign to save the valley. In the end, the Environmental Protection Department rejected KCRC's plan, forcing it to put a tunnel under the bird-watching haven and sending costs soaring to HK$10 billion from HK$8 billion.

But the Long Valley victory was no guarantee that other fights to protect the city's natural environment would be easy. Now, conservationists are fighting an uphill battle to stop CLP Power from building a liquefied natural gas terminal on South Soko Island, and a 38km pipeline.

Opponents point out the damage the projects would cause to key habitat of the endangered Chinese white dolphin and to coral and fish species. But the government gave the scheme the green light in April.

From a focus on nature, conservationists broadened their scope to cover the entire urban area, challenging the traditional wisdom of development at the expense of history and quality of life. Veteran harbour protector Winston Chu Ka-sun kicked off the conservation battle in the urban area by taking the Town Planning Board to court over the Wan Chai North reclamation plan.

The 10.5-hectare reclamation is planned to extend from the Convention and Exhibition Centre towards Causeway Bay. Mr Chu, in the name of the Society for Protection of the Harbour, applied for a judicial review in March 2003, saying the plan violated the Harbour Protection Ordinance.

A separate legal battle against the Central reclamation - which led to the destruction of the Star Ferry pier and the coming demolition of Queen's Pier - was launched a few months later.

Mr Chu forced the Wan Chai reclamation to return to the drawing board, but he failed to address the Central reclamation. The legal battle over Wan Chai laid down the 'overriding public need' test for future reclamation.

One year later, a new fight loomed when two giant developers decided to demolish the brand-new Hunghom Peninsula housing development. Five green groups - the Conservancy Association, Friends of the Earth (Hong Kong), Greenpeace, Green Power and the WWF Hong Kong - signed a joint petition demanding that New World Development and Sun Hung Kai Properties drop the plan.

The Peninsula development had been commissioned by the Housing Authority with a view to selling flats to low-income families. But residents never moved into the new waterfront buildings. In an already ailing property market, the government decided to suspend the Home Ownership Scheme to avoid a glut of new flats.

Instead, the authority sold the project to the two developers, which decided to tear it down and build more profitable luxury residential properties in its place. But the public opposition forced the developers to abandon the plan, and to upgrade the properties by renovation. The petition was later turned into a city-wide campaign against creating unnecessary construction waste and worsening air quality.

Another confrontation occurred over the former marine police headquarters in Tsim Sha Tsui. Cheung Kong Holdings bought the property in May 2003, paying the government HK$325.8 million. It planned to build a heritage hotel, but conservationists were angered by its decision to cut down hundreds of mature trees and remove the Tsim Sha Tsui hill to build a shopping arcade.

They failed to save the trees and the hill, but they used the incident to promote the idea that heritage conservation should not be just about protecting a building. It publicised how the government's tendering process sacrificed heritage conservation for the land premium.

In 2004, conservationists targeted the Tourism Commission's plans to earmark the old Central police station complex for commercial activities. By highlighting what had happened to the marine police headquarters, protesters got the Central project put on hold.

The police compound was designated for tourism-related restoration and development one month before the commission awarded the former marine police headquarters to Cheung Kong.

Heritage advocates helped change skyscrapers, once a landmark of Hong Kong's affluence, into symbols of a suffocating living environment. A young environmental group, Green Sense, rose to prominence when it showed how the KCRC's West Rail property development of massive residential high-rises would create a 'wall-effect' of buildings, blocking air and sunshine. Hundreds of Yuen Long residents filed a rezoning request to the Town Planning Board to turn a West Rail development site into a park. They said the project, if built, would see dozens of high-rise structures blocking the breeze and sunshine from reaching their homes.

John Batten, a former gallery owner, and Katty Law Ngar-ning, a housewife, founded the Central and Western Concern Group to oppose the deterioration of their community. They tried repeatedly through the town planning process to stop the government from selling the married police quarters in Hollywood Road.

Although they failed to persuade the Town Planning Board to share their vision, the pair successfully lobbied the Antiquities Advisory Board to order the Antiquities Monuments Office to conduct an archaeological survey at the plot. Ms Law had found evidence that the site may have housed not only a Chinese settlement soon after the city became a British colony but also the first Shing Wong Temple and later the historic Central School. It remains unclear whether the campaign will succeed.

The government's plan to sell the Bauhaus-style Central Market building and the former government supply depot in Oil Street were also challenged. Conservationists failed to get the two prime sites removed from the land application list, but their efforts forced the government to lower the development density of the two projects. So far, no developers have expressed interest in the two sites.

Meanwhile, new battle lines were being drawn across some of the city's fading precincts. Distinctive communities in older areas such as Wan Chai, Central, Mong Kok and Sham Shui Po found themselves at odds with the push for modernisation being spearheaded by the Urban Renewal Authority. The authority's plans in Wan Chai include tearing down Lee Tung Street, nicknamed 'Wedding Card Street', and the Bauhaus-style Wan Chai Market. In Central, the authority plans to pull down part of the 140-year-old outdoor market in Peel, Graham and Gage streets to make way for hotels, offices, residential towers and shops. Across the harbour, the authority's plans for Mong Kok are also highly controversial. It wants to redevelop part of Sai Yee, Nelson and Fa Yuen streets - known as 'Sneaker Street' for its profusion of sports-shoe shops. The project divided a community: two pressure groups were formed to push the opposing causes - renovation versus redevelopment. That placed the street's business community, on the ground floor, at odds with the residents on upper floors.

Although the Town Planning Board has given the green light to the authority to demolish Wedding Card Street, conservationists have refused to give up. They also vowed to protect Central's street market, the old Sham Shui Po and Mong Kok. Betty Ho Siu-fong, chairwoman of the Conservancy Association, said 2003 was a watershed. 'First, it was the bursting of the property bubble, then came the Sars epidemic. People realised that quality of life was more important than money.'

Anthony Cheung Bing-leung, a City University professor of political science, said: 'The proliferation of conservation campaigns shows the values of Hong Kong people have changed. People demand sustainable development, not unrestricted development at all cost. The conflict has become more acute because the people do not recognise the political system.'

People believed increasingly the city would be a better place if they had a voice in community planning. 'If the government opens up the town-planning mechanism to the public, it will enrich our political system,' Professor Cheung said. 'Universal suffrage is a one-off exercise: people can only vote when there is an election. But genuine public participation ensures the people's voice will always be heard.'