The pink condominium tower under construction between South Boulevard and the trolley line will forever be identified with South End.

But here's another, more important color to consider: green. That's green, not as in tree leaves, but as in U.S. currency.

The City Council committed nearly $20 million three years ago to construction of the trolley tracks between South End and uptown on the premise that development along the line would reap dividends for taxpayers.

Now the city has come up with preliminary figures indicating the strategy is paying off, even before the trolley starts running regularly on the 2-mile segment between Tremont Avenue and 11th Street.

Sixteen projects along the line will generate $4.7 million in city and county tax revenues when all are completed, the city estimates, compared to a mere $240,652 the properties previously produced.

The projected net revenue gain is not too shabby: nearly $4.5 million.

These numbers aren't set in stone. They are strictly projections. But they give us a pretty good idea of what's ahead.

Tim O'Brien, an asset manager in the city's real estate division, said he compiled the statistics by checking the tax values of completed projects and confirming estimated investment costs on projects under construction.

He compared those with the predevelopment tax values on the same property.

There's no way to know for sure whether the investment would have occurred anyway, but the developers of most of the projects specifically mentioned the economic promise of the trolley in their building announcements.

Developer Jim Gross noted, for example, that The Arlington, the pinkish building that will top out at 25 stories, would be constructed with pedestrian access to the trolley tracks behind his 128 condo units.

The project represents an investment of about $50 million. The city said the property previously was valued at $355,950.

The Arlington, under construction on the former site of the old Park Elevator Building, is next door to Factory South, another complex of condominiums developed by Gross.

The Factory South project totaled about $16 million. The property was valued at $249,400 before Gross renovated and converted the old Lance snack foods building to condos.

Among the other big South End investments over the past few years: MECA Properties' Camden Square ($4.9 million) and Camden Row ($3.75 million), Childress Klein Properties Park Avenue Building/Greystar Capital Partners condos ($15 million) and Southern Development Partners' Tompkins Toolworx ($5 million).

The story is similar, but not as widespread on the uptown side of the trolley line.

The 30-story Westin Hotel project, under way across from the Convention Center on Stonewall Street, is being constructed to accommodate the trolley line through uptown. It's an estimated $140 million investment.

All of this new development has occurred on the promise of the trolley line, which offers demonstration rides but won't begin full service until late 2002, and the light-rail transit system, which will share the rail corridor with the trolley in late 2005.

Someday, planners say, we'll see stations with concentrations of track-oriented shops, services, entertainment and, in some cases, housing along the line.

More projects are in the works.

Pappas Properties and Crescent Resources expect to start early next year on Manchester, a retail/restaurant/residential village on 6 acres that housed Duke Power's trolley barn on South Boulevard. And The Crosland Group plans apartments at South Boulevard and Griffith Street.

Uptown, planners see the old convention center at College and Trade streets eventually being redeveloped and oriented toward the trolley line.

Viewed 20 years ago simply as cute demonstration of Charlotte's history, the trolley does appear to be living up to its promise as a property tax generator.

The 16 projects tallied by the city have a total projected value of $393.15 million. The property previously was valued at $20.1 million.