DIGITAL TV MAY BE SHORT ON TOWERS : FEW CREWS READY, SITES HARD TO FIND.

Byline: Joel Brinkley The New York Times

In Austin, Texas, construction had to be halted for several months during the nesting season of the golden-cheeked warbler.

In Dallas, a construction accident killed three people because workers had not been properly trained.

And in New York, even the city's tallest skyscrapers may not be up to the task.

For the few companies in the business of building television towers, the prospect of bizarre complications, bureaucratic delays and even fatal mistakes only serve to compound the extraordinary challenge now facing them.

Under a federally mandated schedule to usher in digital high-definition television - a timetable that the construction industry says may be impossible to meet - the tower builders are embarking on a crash program across the country to build hundreds of new television towers, at heights up to 2,049 feet, taller than the world's tallest buildings.

The trouble is, across the United States only about a half-dozen crews have the experience and training to put up these towers that can reach nearly a half-mile into the sky.

Together, all of the nation's tower building teams may be able to put up as many as 20 towers a year. But each year for the next four or five years, the broadcast industry is going to call on them to build 100 or more. Broadcasters and tower builders call it a Sisyphean mission. And if they do not succeed, many of the new digital stations will be years late going on the air.

``I don't see how we can get it done,'' said J.C. Kline, president of Kline Towers, one of only three companies in the United States that build television towers. ``We just don't have the capacity for this.''

Scores of engineers, politicians, lobbyists and bureaucrats spent more than a decade in a tortured, government-run program to devise the standard for the new generation of television. Now that the standard is set, and the Federal Communications Commission has lent every television station a second channel for the transition to this new service, 1,600 stations have to find places for the antennae that will beam the new programming to their viewers.

Nearly all of them had chosen to defer even thinking about this problem until now, in part because a new tower costs at least $1,000 a foot, or $2 million for a 2,000-foot structure.

Digital television does not demand a tower any different from what conventional broadcasting requires. So in many cases, existing towers may suffice. But as many as one-third of the nation's television stations may have to put up new towers because their existing ones are loaded to capacity with antennae for television and radio stations, cellular phone providers and other communications systems. For these fully loaded towers, even one more antenna - along with up to 2,000 feet of fat copper cable leading to it - would add more weight than the tower could bear.

Different stations have different height requirements for their towers, depending on terrain and the distance to the city's farthest suburbs. The higher the tower, the farther the signal's reach. But 2,049 feet is the tallest tower allowed by federal law.

The National Association of Broadcasters and Tom Vaughan, an industry consultant who specializes in towers, say their recent surveys of the nation's television stations indicate that 500 to 700 of them will need new towers. And while some broadcast executives think those numbers may be a bit too high, most of the stations have hired engineering firms to determine whether their existing towers can be reinforced or modified or whether entirely new structures are necessary.

But whatever the final number of new towers turns out to be, broadcast executives know the sheer national scope of the task will be daunting.

``It's something the world has never had to face up to before,'' said Bob O. Niles, who is in charge of the tower-building program for ABC, which owns 10 stations and expects to erect new spires for two of them. ``It's a serious problem.''

One of the ABC stations, in Philadelphia, is joining forces with the CBS station there to build a tower on land that has already been set aside for television towers.

But in most other metropolitan areas, site selection will not be as easy. In New York, for example, executives for the region's 12 television stations know there is no room to add more antennae to the existing towers atop the World Trade Center. So they are exploring several possible solutions: persuading the Port Authority to let them build a shorter, third tower beside those already on the World Trade Center; sharing the CBS auxiliary tower on top of the Empire State Building; finding other tall buildings in New York that can support towers, or building a 2,000-foot freestanding tower somewhere near Manhattan.

But each of these ideas faces its own formidable engineering and bureaucratic problems.

``Nobody is really sure yet which way we are going to go,'' said Lev Pope, who is running an intra-industry committee that is trying to solve New York City's tower problem.

Until early April, the tall-tower industry had been a sleepy little business that had been depressed since the early 1980s, when growth in the television industry slowed. In recent years, Kline along with its two friendly rivals - LeBlanc Communications Inc. and Stainless Inc. - have together been called upon to build maybe 10 or 15 tall towers a year, as new stations have gone on the air and existing stations have occasionally replaced towers.

Building towers is rugged, skilled, dangerous work, and ``right now I would be surprised if even a dozen crews in all of North America have the training to do it,'' said John Miller, president of LeBlanc.

And that is just one of the problems.

The challenge begins when a station tries to find suitable land. Most television towers in use today were built in the 1950s or '60s. Some were placed right next to the stations; others were put up in corn fields or pastures on the edge of town.

In the years since, insurance companies have begun to require television stations building towers to use land large enough that the tower can fall in any direction without hitting anything - meaning that in some cases a circular plot with a diameter of 4,000 feet is needed. Towers do in fact fall on occasion. Seven of them collapsed during a storm in Minnesota and North Dakota last month. No one was injured.

The new insurance requirement makes it unlikely that many stations will be able to build towers next to their offices. And sites outside town have their own problems. Since the '50s, the suburbs have grown up around the towers - and beyond.

In Denver, for example, where one or more new towers for digital antennae will be needed, ``all the broadcasters put their towers up on a mountain outside town 35 years ago,'' said Robert J. Ross, the CBS vice president who is running the network's tower-building program.

``Back then it was just pine trees and dirt roads with lots of switchbacks. But now there are a lot of million-dollar homes out there.''

As a result, the area's zoning has changed, ``and we can barely touch the existing towers without lawyers and variance hearings,'' Ross added.

``I don't know how we're going to get a new one up,'' he said.

Once a station does find a large plot of land for a tower, the next set of challenges will begin: winning permission to build it. Nobody, it seems, wants a tower in their back yard.

``It's easier to get permission to build a prison,'' quipped Joseph Flaherty, a senior vice president for CBS.

David Brotzman, administrator of the National Association of Tower Erectors, said a recent project in Blooming Prairie, Minn., had to be relocated at the last minute when environmentalists complained that it was going up in the migratory flight path of a certain breed of duck.

And in San Francisco, residents complain about the suspected ill effects of the radio waves emanating from the antennae - though there is no proof that television signals, digital or otherwise, are hazardous.

San Francisco's 10 local stations plan to add antennae for digital broadcasts to an existing tower at the Sutro tower complex atop a ridge just above the city's Twin Peaks neighborhood. ``But I guarantee it will be held up,'' Ross said.

``A few years ago, we wanted to build just an addition to the building there, and residents came out of the woodwork talking about all kinds of cancers, all kinds of headaches,'' he added. The project was scrapped.

There has been little public discussion of the plan to add antennae at Sutro, and at ABC, Niles said, ``We don't know what will happen when the public finds out about this.''

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Photo

Photo: Workers in a Dallas suburb erect a television transmitting tower for KXAS-TV.

The New York Times