Chattanooga on a roll: from America's dirtiest city to one of its greenest.

"Chattanooga," proclaims a 1924 promotional brochure whose cover features artistically rendered belching smokestacks, "is a divine masterpiece in the making." Unfortunately, the roaring fires of this industrial riverfront city came to symbolize something other than progress. By 1969, just before the first Earth Day, the Environmental Protection Agency had bestowed on Chattanooga a special award for being "the dirtiest city in America." Visitors to Lookout Mountain, which boasts a view of seven states, were lucky if they could see two.

But look at Chattanooga now. The Clean Air Act forced city, manufacturers to invest in $40 million worth of pollution control equipment, and by 1988 the city's air was "in attainment." That was only the beginning. Who knew that Chattanooga would soon become as green as Peter Pan's tights? The city can now boast of a leaf-lined river walk along its redeveloped downtown, a freshwater aquarium where conservation is the byword, a free electric bus shuttle, the world's longest pedestrian bridge, and plans for a zero-emissions eco-industrial park and a grass-roofed convention center. Vice President Al Gore said in 1995 that Chattanooga "has undergone the kind of transformation that needs to happen in our country as a whole."

Sustainable development works for Chattanooga because it's not a top-down imposition, or a marginalized protester's demand. The scaffolding visible throughout the city symbolizes a democratic process that reaches into every city neighborhood, including its poorest housing projects.

Rebuilding Chattanooga was a slow, incremental process. "There was a sense of doom in the air, and the future seemed foreclosed," says lack Murrah, executive director of the Chattanooga-based Lyndhurst Foundation, about the period in the early 1980s when the city hit rock-bottom. It was Lyndhurst itself, with an endowment from the city's Coca-Cola heirs, that began the renewal process in 1981 with a series of free downtown concerts. By 1984, Lyndhurst and the new Chattanooga Venture were collaborating in the "Vision 2000" program, which called on all city residents to imagine a future for their city. A remarkably progressive agenda emerged, calling for downtown and riverfront development, improved inner-city, housing, and a whole host of sustainable projects - 233 in all.

The Riverwalk, construction of which began in 1989, was the first tangible sign that the city could be reinvented. The Tennessee River, potentially a great asset to the city, had been lost to pollution from the industrial sites that lined its banks. If residents experienced the river at all, it was in the form of filthy water seen through a chain link fence. Riverwalk, which is in the process of reclaiming 22 miles of waterfront (seven miles are completed) for a hugely imaginative urban park, cuts through the heart of the city with playgrounds, performance spaces, fishing piers and leaf-shaded walkways. Today, you can watch blue herons feeding along the shore or do some fishing yourself from one of five piers. You can even eat the fish.

The Riverwalk began the transformation of Chattanooga's tired and polluted downtown. "Within the 500-acre area of downtown, we were faced with a very ambitious brownfield exercise," says David Crockett, the larger-than-life City Councilman (and, yes, descendant of frontiersman Davy) who crusades tirelessly for a sustainable Chattanooga. "There's an art to doing it so that you don't get bogged down, and full public participation - which we had - is crucial. There have to be both wingtips and hunting boots under the table."

The $45 million Tennessee Aquarium, which focuses on freshwater ecosystems and features a kid-focused environmental research center, opened in 1992 and serves as a downtown magnet and anchor. Around the aquarium now are warehouses that have been reclaimed as smart shopping malls, newly renovated affordable apartment buildings, and restaurants sandwiched within the rough walls of old factories. Through the newly enfranchised Chattanooga Neighborhood Enterprise, 3,460 units of inner-city housing have been built or renovated - again, through a fully public planning process.

To get around the new user-friendly downtown, in 1993 Chattanooga created a unique - and free - 17-vehicle electric shuttle bus service. Chattanooga is actually the world's electric bus capital; it exports the 22-passenger models made in town by Advanced Vehicle Systems (AVS) to seed similar shuttle programs in Miami Beach, Burlington, Vermont, Portland, Oregon, and 11 other cities. AVS buses have also gone international: the city is working on a pilot program with San Jose, Costa Rica, and delegations from Sweden and Switzerland have come to take a look at the system.

Chattanooga's shuttle is a real hint of our transportation future. Far from just a demonstration project, it's a vital part of downtown redevelopment, helping keep the streets unclogged. Commuters are encouraged to leave their cars in parking garages on the outskirts of town, then take the shuttle in. City officials say the shuttle moves a third of the ridership at a tenth the cost of their own much larger diesel service.

AVS Operations Manager Alan Clark says the company was founded because Chattanooga wanted to run electric buses, and preferred to award its contract to homeboys. But AVS is not a heavily subsidized nonprofit, it's a thriving private company, with exciting plans for a hybrid turbine-electric bus.

On a recent fall morning, Chattanooga was playing host to a sustainable development planning conference. Katie McGinty, chair of President Clinton's Council on Environmental Quality, breezed in quickly, calling Chattanooga "a model for the nation and the world" Bill McDonough, dean of the architecture school at the University of Virginia and a world-renowned eco-designer, talked about his work for the city, which includes design of a new grass-roofed trade center, and consultation on the creation of a model eco-industrial park (that will recover and recycle waste energy) in Chattanooga's Southside Redevelopment Area. "Wouldn't it be great if we could eliminate the concept of waste?" he asked. McDonough was surrounded not by politicians and journalists, but by ordinary Chattanoogans, whose comments and suggestions became part of the process.

Across town, Jack Murrain of Lyndhurst was asked if he's satisfied with how far Chattanooga has come. He looked horrified. "Oh, no" he said. "We're only 20 percent there." CONTACT: Electric Transit Vehicle Institute, 1617-B Wilcox Boulevard, Chattanooga, TN 37406/[phone]; Chattanooga News Bureau, 1001 Market Street, Chattanooga, TN 37402/[phone].