If any part of the broadcast plant ever merited the label “necessary evil,” a top nominee would be the tower.
Expensive to maintain, fraught with potential hazards, bound by an ever-growing web of regulations, unloved by neighbors and often located inconveniently far away, a pubcaster’s tower still serves as the essential link between its program service and its audience.
In the early years of public TV and radio — before streaming and podcasting and cable and over-the-top video delivery — pubcasters and their audiences depended completely on the reach of the signals their towers could deliver. When broadcasting was a new and developing communications medium, those towers were much easier to build. As long as they weren’t in an airport flight path, the NIMBY factor was rarely a concern as public TV and FM stations spread across the country from the 1950s into the 1970s.
Today, the scene has changed dramatically. Just a few years after the DTV transition forced pubcasters to install new transmitters and antennas, the prospect of spectrum auctions and channel repacking has many questioning the cost and challenge of maintaining pubcasting’s infrastructure. Whether stations own their towers outright, partner with commercial colleagues or lease space from for-profit tower companies, they face new competition for scarce antenna space in the air, an increasing regulatory burden and, often, increasing costs to keep their towers functional.
The empty space that existed in profusion on tall towers in the early days of TV has evolved into a valuable commodity called “vertical real estate.” TV stations whose towers once had only one transmitting antenna today find that they are loaded to their capacity limits. A typical TV station tower now has multiple receiving antennas that relay signals back and forth from its studio and mobile units as well as space leased to FM broadcasters for their antennas.
In recent years, a profusion of wireless providers have been seeking tower space for their antennas — and offering tower owners plenty of rent money for the privilege.
“There’s just a general shortage of tower space, period,” says Joe Tymecki, director of technology and engineering at Vermont Public Radio. “There are a lot of people trying to deploy wireless Internet, they can’t upgrade 4G LTE wireless fast enough and all those installations really eat into the capacity of the tower.”
Boston’s WGBH takes its famous call-sign from Great Blue Hill, the spot south of Boston where WGBH-FM has transmitted since 1951. Its sister stations, WGBH-TV and WGBX-TV, use a tower in Needham, a western suburb of Boston. When commercial station WBZ-TV built the Needham tower in 1957, it offered WGBH free space in a deal that lasted to the turn of the century.
After being extensively rebuilt for digital TV and sold several times, the Needham tower now counts WGBH and WGBX among its paying tenants. Responsibility for its maintenance belongs to current owner American Tower, the largest commercial operator of broadcast towers in the U.S.
In today’s broadcast environment, a tower leasing agreement can come as a relief, says Stacey Decker, WGBH chief technology officer. “The liability of owning a piece of vertical real estate is reduced significantly,” he says of his stations’ tenancy on the Needham site. “If you can share in the costs of utilities and lights and real estate with another entity, it’s not a bad thing.”
Decker speaks from experience: In previous posts as an engineering executive at South Dakota Public Broadcasting and Nebraska Educational Telecommunications, he oversaw statewide networks of tall towers built for and managed by public TV and radio.
In addition to the TV transmitters at Needham, WGBH still owns its original Great Blue Hill tower, though it sits on land owned by the state. That tower is used by WGBH-FM, which in turn leases space on the tower for a commercial FM station, NOAA Weather Radio and several other tenants.
Let’s be partners
The demand for space and the difficulty of siting new towers has created a wide variety of arrangements for pubcasters all over the country.
While many still own and maintain their own towers, especially in more remote or rural areas, some have become vertical landlords in their own right, leasing space to other tenants.
Some pubTV stations used the DTV transition as an opportunity to become tenants, either by taking space on commercially owned towers or selling their towers to commercial operators. And in an era when few commercial TV operators feel compelled to offer free tower space to pubcasters, some public and commercial stations have teamed to share the costs and potential rewards of tower ownership.
Wisconsin’s state-run networks have some of the most extensive experience in these “community towers.” In Madison, the flagship stations of Wisconsin Public Television and one of Wisconsin Public Radio’s networks transmit from a site owned by the University of Wisconsin and shared with several commercial TV and FM stations. To the north, in Wausau, the state’s Department of Natural Resources pushed three commercial broadcasters and the state-run Educational Communications Board to join forces atop Rib Mountain, a 1,924-foot peak that rises from a state park.
With digital TV fast approaching at the end of the 1990s, state officials wanted all the stations broadcasting from individual towers on Rib Mountain to combine their operations on a new tower, using the site of ECB’s Wausau stations, WHRM-TV/FM.
“The land is owned by the Department of Natural Resources. We own the transmitter building, a consortium of us and three other commercial partners own the tower, so there’s a lot of pieces in there,” says ECB executive director Gene Purcell. Unlike in Madison, where pubcasters WHA and WERN function simply as tenants, ECB’s role as a partner in the Rib Mountain site required political skills in addition to technical knowhow.
“Renting tower space isn’t like being a partner in a house with roommates,” says Purcell. This was especially true in the early years of the DTV transition, as ECB and its partners worked out technical specs for the tower and transmitter building, and how they’d divide the costs of constructing and maintaining the facility. Their needs and costs changed often as the project evolved.
“It really tested the limits of our partnership to survive it,” Purcell says. ECB representatives meet regularly with their Rib Mountain partners, making ongoing decisions about technical and business aspects of the partnership. “It’s one of those things where the status of the relationship at any given moment depends on the people who are sitting in each of those chairs,” says Purcell. “Right now we get along very well, but there were a lot of growing pains in trying to figure out who would be responsible for what.”
Whether a pubcaster owns a tower outright or partners with commercial stations, those responsibilities are often substantial.
Welter of regulations
Unlike most other aspects of broadcasting, tower construction and operation falls under the direct purview of at least two federal agencies. Both the FCC and the FAA regulate broadcasters’ tower usage, and their regulations are among the more onerous that pubcasters face.
On the FCC side, all towers 200 feet or taller (and some shorter ones as well) must be registered in the Antenna Structure Registration database. Some of the first details an FCC inspector tends to check are whether a tower’s ASR registration is current and if the ASR number is properly displayed on the signage the FCC mandates at each tower site.
The FAA, for its part, enforces strict regulations ensuring that towers are properly painted and/or lit for maximum visibility to pilots. If tower lights go out for any reason, owners must report outages so the FAA can alert pilots to the hazard. They face stiff fines if they fail to make those reports.
Many of the FAA’s rules closely parallel those of the FCC, and in August the commission attempted to streamline the regulatory burden for broadcasters. The FCC revised its tower rules to automatically incorporate the latest versions of the FAA’s regulations.
Keeping both sets of regulators happy takes time and effort. In both Nebraska and South Dakota, Decker employed a full-time staffer whose job was dedicated to FCC compliance for the multiple licenses held by each statewide network. In Boston, he says, compliance is a major task for WGBH’s legal department.
For stations seeking to build new towers or add new antennas to existing towers, the welter of regulations gets even more intense. To construct a new tower, broadcasters have to conduct environmental impact studies that examine endangered species in the area, protection of migratory birds and even the possibility of disrupting sites of archaeological significance.
“If the local college comes in and finds artifacts, that could significantly delay a project,” says Vermont’s Tymecki. He persevered through years of delays to put a tower for digital TV transmissions atop Mount Mansfield, the state’s tallest summit.
At the time, Tymecki worked for a commercial station, WCAX-TV, which had been on the mountaintop since it signed on in 1954. Tymecki headed the technical committee that sought to combine most of the commercial and public users of Mount Mansfield into a single community site. That included VPR’s flagship, WVPS-FM, but not Vermont Public TV, which kept its own separate tower site on the mountain.
The process consumed most of a decade as the tower project pushed up against some of the most stringent environmental laws in the nation. When it was finally completed, in 2009, Burlington became the last TV market in the country with DTV. Tymecki says the experience foreshadowed the challenges just about any broadcaster, public or commercial, now faces if it attempts to build a new tower.
“The single biggest thing now is the amount of time it takes,” he says. “This used to be true just in Vermont, but now it’s everywhere.”
Keeping them standing
The first generation of towers that went up for public TV and FM are now approaching their 60th birthdays, and the hundreds of tall towers that filled in pubcasters’ coverage during the boom years of the late 1960s and 1970s are aging as well. That poses its own set of challenges for the engineers charged with maintaining them.
“For the towers we own, we do inspections twice a year. That’s something we write into our budget,” says Terry Baun, director of engineering for Wisconsin’s ECB. That inspection process alerts ECB to problems that might be developing, potentially averting the sort of catastrophe that brought down a 2,000-foot tower that had been the state’s tallest when it collapsed during a winter storm in 2011. That tower belonged to a commercial TV station, not to ECB, but its collapse has been a powerful reminder of the need to make sure ECB’s towers don’t get overloaded with tenants.
“Here at ECB, we’ve had a policy in place since the 1990s that gives us first priority,” says Purcell. “Other state agencies come second, then local public safety, and only after those needs have been satisfied will we open up space” for outside users to lease.
State-supported pubcasters like Wisconsin face less pressure to earn revenue from tower space rentals. “Our primary business is public broadcasting,” says ECB’s Purcell. “If we can make some money, that’s fine, but that’s not what we set out to do.” ECB doesn’t disclose leasing revenues in the financial statements it releases publicly. At WGBH, the revenues earned from tenants on the Blue Hill tower are minimal, according to spokesperson Michael Raia; the pubcaster passes most of the income through to the state agency that owns Blue Hill.
For smaller stations, though, income from tower rentals can provide a significant financial boost at a time when new revenues are hard to come by. During Tymecki’s tenure as engineering chief at Vermont Public Television (now Vermont PBS), tower revenues were an important budget line. By his estimate, the network took in more than $800,000 a year by leasing space on its towers around the state. Tenants include his current employer, VPR, as well as commercial broadcasters and wireless providers.
In at least one case, a potential tenant paid for upgrades to a VPT tower after a structural study found it needed some $35,000 of work to be able to hold additional antennas. Tymecki says older towers can often be brought up to current standards with the careful replacement or reinforcement of certain parts of the structure, a far less daunting task than completely replacing an entire tower.
The conversion from analog to digital TV a decade ago made many of the nation’s towers stronger, too. Many of the towers Decker oversaw in South Dakota and Nebraska had to be reinforced to hold two sets of antennas, one for analog and one for digital operation.
“During that time, we probably added some safeguards in that wouldn’t have been added in the past,” he said.
Even if a pubcasting tower can support the load of outside tenants, there are other concerns to consider before leasing out space. Many wireless companies seek lease terms of 20 years or more, a longer commitment than some stations are willing to make. Even if the potential revenue is worth the long-term commitment, Decker says a lease agreement should include a provision stipulating that when a tenant leaves, its equipment comes down to make room for other potential tenants.
Safety and security are constant concerns as well. In Wisconsin, tenants are not allowed to send climbers up the tower to do repair work without an ECB representative on the premises and an insurance certificate on file. As the number of stations sharing tower sites grows, coordinating tower work becomes a logistical challenge.
It’s important to maintain good relationships with tower crews and other broadcasters that share towers, notes Vermont’s Tymecki. If climbers need to temporarily turn off one of VPR’s transmitters so they can safely complete a repair, “we don’t want them doing it during Morning Edition or All Things Considered,” he says. By contrast, a TV station on a tower is less likely to want work to be done during prime time or the late news.
Towers into the future
For public TV stations that spent millions of dollars building out DTV infrastructure just a few years ago, the FCC’s plans to auction television spectrum and restructure channels within each market have complicated planning for stations trying to assess just how much tower space they’ll need in the future.
Even pubcasters like Wisconsin’s ECB that have long resisted public-commercial partnerships could find themselves sharing tower and transmitter space if the FCC’s vision for channel sharing comes to pass. As hazy as that vision appears now, Decker says it opens up potential for some pubcasters in search of more revenue, especially if channel-sharing frees up tower space that they can then lease out to paying tenants.
The channel-sharing agreement announced Sept. 9 — the only one to be disclosed so far — won’t require many changes in the tower configurations for the broadcasters involved. KLCS in Los Angeles is already a paying tenant of long standing at the Mount Wilson tower site of its future partner, KCET; its owner, pubcasting licensee KCETLink, also leases space at that site to several commercial FM stations.
In some cities, it may be possible to build new towers atop existing tall buildings, with transmitters on one of the top floors of such buildings.
It may prevent “NIMBY”‘s, but if it’s not the tallest structure in the city, it could post reception problems, especially I would think, with digital TV signals.
Yes and no. If a tall building wasn’t designed from the beginning to handle a tower on the top, it’s relatively unlikely to be able to accommodate one. As the saying goes: “you don’t add floors to the top of the structure, you add them to the bottom.” The weight- and wind-load stresses from a rooftop tower can be substantial…even for a relatively short tower in the 50 to 100ft range. And for high-power installations, a short tower is often not a realistic option due to RF Energy exposure/safety concerns for people on the top floor. Yes, careful antenna array engineering can alleviate a lot RFE issues, but that dramatically restricts how many tenants can use your tower, too.
Obviously, of course, this is all done on a case-by-case basis. And any architect of a new tall building worth their salt designs it with a broadcast structure in mind on the top…even if it’s ultimately not built, it’s relatively cheap and easy to have the necessary structures inside in the building ready to go to add a tower later.