May 2009

Storm Chasers

When storm clouds gather, Power System Operations employees prepare behind the scenes to support the crews on the scene.


TVA’s chief storm-tracker Patrick Walshe monitors the weather and forecasts the daily peak demand for the region’s power use.

In the first week in April, Power System Operations’ Patrick Walshe saw something brewing on the southeastern edge of the TVA service area. “We saw something interesting six or seven days in advance,” he says. It was a weather pattern that resulted in three tornadoes, one on April 3 on the Tombigbee River in Alabama, and two more the week after — one on Sand Mountain, Ala., and the other in Murfreesboro, Tenn.

Walshe is trained as a meteorologist, and his job as manager of Short-Term Load Planning includes projecting the Tennessee Valley’s weather 10 days out. Each day, he forecasts the daily peak demand for the region’s power use, based on temperature, weather conditions and peak load history. In general, he nails each day’s peak within a hairs-breadth — 2.1 percent. But his job gets more interesting when he sees a bad moon rising.

Like many in his field, Walshe decided early on that he wanted to be a weatherman. “Even when I was 6 or 7, I had a favorite weatherman, a guy in Atlanta named Guy Sharpe,” he remembers. Walshe earned his meteorology degree from Florida State University, worked 12 years at The Weather Channel, then joined TVA six years ago.


LEFT: Ground foreman Chris Garner, left, and apprentice lineman Jayson Allison “lace” or assemble steel on the Widows Creek-Eastpoint line that was damaged by a tornado. CENTER: Structure No. 175 was crushed to the ground by the tornado. RIGHT: Linemen Eric Lawson, left, and Jason Johnson finish placing protective grounds on one of the conductors.

Whether it’s hurricanes and tornadoes or snow and ice, Walshe has become an expert at giving advance warning on weather patterns that can wreak havoc on TVA’s transmission system.

The warning before the storm

During the warmer months, Walshe says he keeps a special eye on developing hurricanes, which cover larger expanses of territory, as well as the weather patterns that can generate tornadoes or destructive thunderstorms, like the ones in April. “These types of storms can be more localized or focused on a particular area of the Valley,” he says.

When Walshe sees the patterns developing, he notes them in his long-term forecasts and works to assess the potential risk, primarily to the transmission system and distributors, so they can be prepared to swing into action.

Two days before the January ice storm, for example, Walshe issued an advisory that a significant severe weather event was coming. “It was one of those things you don’t see too often. The last time was in February 1994.” Walshe’s advisories generally go to some 230 people, including those in TVA who notify customers. As the ice storm hit, TVA transmission kicked into its well-tested procedural response, which has been refined over the years like the methods of elite commando units.

Weathering the storm

The Transmission Emergency Operations Center was activated in Chattanooga, in support of customers and TVA alike. The TEOC functions at a strategic level to focus resources on restoration support. Damage assessment and repair is handled by Transmission Operations & Maintenance and Electric System Projects in the field. The System Operations Center manages restoration coordination, provides grid status updates and assigns restoration priorities.


LEFT: Groundman Robert Eaton, left, and aprentice lineman Jayson Allison lace steel with structure. CENTER: Structure No. 174 was one of the many mangled by the tornado. RIGHT: Line crew members from left, Greg Appleberry, Jeremy Swafford and Andrew Hall prepare to lace steel.

“During the first six days of restoration, our transmission operators in the SOC fielded about 6,000 calls,” says Doug Bailey, manager of Transmission Operations. “There’s a lot of switching required to restore power to the affected areas.”

Bill King, manager of Transmission Line Construction, works closely with TOM to ensure restoration crews have equipment, food and lodging. For this ice storm, some 200 PSO crew members were working 16-hour days.

“One of the keys to a good restoration is logistics, logistics and logistics,” says King. “If people are well-rested and provided good meals, then the potential for injury is lessened and productivity is increased. We don’t need our employees driving around after a 16-hour day looking for a hot meal. The payback for all is highly productive and safe work, which simply reduces the time for system restoration.”

In addition to rebuilding transmission infrastructure, King’s group finds and arranges sleeping accommodations for crew members. And he coordinates food service to provide eating locations in climate-controlled tents near damaged areas. Such service includes a hot breakfast, a boxed lunch and a hot dinner.

“As an old lineman myself growing up and working many years for a Florida utility, I have worked many hurricanes. One of the joys of being part of a major storm-restoration effort is having the opportunity to make a difference by helping others.”



From left, Bill King talks with Robert Wilson, an environmental scientist who supports Transmission Line Projects, and Joel Stansberry, supervisor of Right-of-Way Services.