A Smack From AboveIt was a powerful wind that blew through St. Louis the evening of July 19, 2006 . Forecasters did not see it coming, so there was little, if any, chance for broadcasters to get out warnings. But even if they could have foreseen it, it would not have helped KTRS.
After the fact, a National Weather Service spokesman said the St. Louis region experienced a series of north-northeasterly downbursts, which included several microbursts. The storm, he said, is called a “derecho.” Anything in the path of the wind was in danger, including radio towers.
Just a couple miles northeast of downtown St. Louis , the tower site of KTRS was hit hard. The four-tower array was built on the Mississippi River flood plain in Illinois half a century ago. Two of the station’s four Blaw-Knox towers were felled that July evening. A National Weather Service spotter in nearby Bunker Hill , Il., recorded a gust of 92 miles per hour.
Now, KTRS station ownership must cope with an extensive rebuilding process, made more costly and complicated by the possibility that all four towers are covered with lead-based paint.
The transmitter facility was built by Pulitzer Broadcasting in 1948 for its St. Louis station, KSD. Officially activated November 22 of that year, the towers were constructed during a major expansion of the broadcast facility, which included the establishment of the market’s first television station and a signal upgrade that gave KSD 5,000 watts, both day and night.
A St. Louis Post-Dispatch story heralding the site construction noted each tower was 450 feet tall and weighed 70,000 pounds. The westernmost tower ran a 5,000 watt daytime signal and, with the other three towers, providing the 5 kW nighttime pattern. At that time, there were 16 stations at 550 kHz; KSD had to protect WKRC in Cincinnati , WJIM in Lansing , Mich. , and KFYR in Bismarck , N.D.
Each tower leg sat on a concrete pyramid base. “At the base of each tower is a small building which houses the apparatus used for tuning the antenna to serve its special part in broadcasting KSD programs and preventing interference with other stations,” the article revealed. “The transmitting apparatus is housed in a building about 830 feet from the westernmost tower.”
Development of the site had taken two years, as the F.C.C. construction authorization came December 9, 1946 , a time when materials were scarce due to World War II. The 68-acre plot of land - rural at the time of construction - is still considered remote today, surrounded by cornfields and a huge landfill.
“It’s one of the great old tower sites,” says KTRS chief engineer Mike Breitenstein.
Mother Nature has shown destructive powers throughout history, but recent history in the St. Louis area had been relatively calm. When the wind storms rolled through on that evening in mid-July, the destruction that was left behind was incalculable. Thousands of trees were uprooted or destroyed. A large percentage of them fell on electrical wires.
The local electric utility, Ameren Union Electric, estimated 500,000 homes were without power – it was the largest outage in the history of the utility. The emergency was the logical time for the public to turn on battery-operated radios, and it was the wrong time for a talk-format station to be off the air.
The Benefits of Planning Ahead
Breitenstein says the station was quick to recover from the effects of the loss of two towers that night, in part because of something he did several years ago.
“In the late ‘90s I created a second non-directional tower,” he says. “We needed it for those times when maintenance was necessary. It gave us the ability to continue a non-directional signal during those times when we had to perform maintenance on the primary non-directional tower.”
So when the July storm hit, felling two of the towers, “I was able to get us back up and running within a couple hours,” Breitenstein said. “I took us down to 500 watts until we got the [FCC’s] authorization.” After the station’s signal was restored, KTRS was able to switch into a local mode in which the programming focused on storm damage and making sure listeners got the information they needed for their safety and recovery.
Station manager Craig Unger says their Washington attorneys were in the FCC offices the next morning. They asked for and got permission to go with a nighttime signal at 1250 watts, non-directional, rather than the normal 5,000 watts, directional. The Commission gave the station an initial six-month Special Temporary Authorization (STA) window for repairs.
Assessing the Damage
In the daylight following the storm, KTRS management was able to gather information on what had transpired. “You don’t really understand the magnitude and power of a storm until you see something like this,” said manager Unger.
Breitenstein said it looked like the failure point had not been in the towers’ steel structure but rather in a much smaller part. The steel, he says, was in good shape, even though the towers were 58 years old. But the Lapp insulators appear to have been the weak points.
Those insulators failed,” he said. The National Weather Service spokesman said the highly variable winds at excessive speeds put unnatural stresses on everything. Hardest hit, he said, were trees that were subjected to twisting.
In the case of the KTRS towers, it appeared the winds exerted stresses that shattered the insulators at the base of each tower. One tower simply collapsed. The other, Breitenstein says, looked as though it had been picked up completely from its base and deposited next to it, where the structure collapsed. He said there were distinct prints from the tower’s four legs in the soil next to the base.
A station employee had an apt description: “It looked like it had jumped,” he said.
Looking Ahead and Planning
For KTRS ownership, the storm may have a silver lining. They had recently installed a new transmitter in an effort to improve nighttime coverage. Now the loss and subsequent tower replacement could further that effort by giving KTRS a chance to improve its night pattern. The timeline, says the station manager, is loose right now.
Insurance will help, says Unger, “but as all station managers know, the insurance manual for this sort of thing is usually about 80 pages long. We’re getting bids now and weighing our options.”
Those options could include relocating the nighttime towers to a new site, but that’s not too likely. In any event, nothing can be done until the Illinois Environmental Protection Agency checks out the lead content in the old tower paint. Unger believes there’s no real problem there, but station ownership will have to go through proper channels when it comes to disposal of the scrap metal - and that disposal may not be limited to the two flattened towers.
Unger says consulting engineers will probably be brought in to design a new site plan for four new towers. “There’s great ground conductivity out there in the flood plain,” he says, “and we want to continue to take advantage of that. There are probably a lot of different things we can do with that site.”
In the meantime, thanks to Breitenstein’s planning, KTRS continues to pump out the watts, serving its listeners during fair weather and foul.
(Reprinted with permission of Radio Guide. Originally published 9/2006)