Articles

10th Anniversary of 2011 Tornado Outbreak

Tornado approaching Guntersville Dam in 2011.

Unforgettable

April 27, 2011 started like any other mild spring day. But after three waves of severe storms and tornadoes struck the area, entire communities in the TVA region were devastated and the TVA system sustained the worst damage in its history. That’s when TVA employees and contractors, in partnership with local power companies, communities and neighbors banded together to demonstrate the resilient power of the Tennessee Valley.

Unprecedented System Damage

TVA’s system damage included more than 350 transmission structures and 100 lines out of service, 75 local power companies affected due to 128 connection points with TVA being interrupted, and most north Alabama and Mississippi in the dark. At the peak, nearly one million consumers were without power.

TVA also lost 5,200 megawatts of generation from 12 plants going offline, including all three units at the Browns Ferry Nuclear plant.

Following damage assessments, restoration was prioritized to return power to the nuclear plant, life-safety critical loads and customer connections. Black start strategies were developed to restore power to north Alabama and Mississippi. Browns Ferry’s diesel generators kept the plant in safe shutdown condition until off-site power was reestablished five days after the storms. Rebuilding the 500-kilovolt system was necessary before the plant could return to full operation.

The entire TVA team came together and rallied behind getting the most critical segments back in service as fast as possible. All transmission construction, maintenance and contract crews were mobilized to begin rebuilding the system. An estimated 4,000 people worked to restore service, including many who supported the boots on the ground. And with only 25 percent of the structures repaired and 40 percent of the lines restored, power to almost all customers was reestablished.

Through the creativity of operations and engineers, a grid was cobbled together from the least damaged components despite only 25% of structures being repaired. TVA rapidly put in place a grid that supported almost 100% of our customers returning to service, which was truly remarkable.

It would be 74 days later in mid-July when the last two transmission lines in north Alabama were returned to service, completing the final transmission repairs. The restoration effort required 1,400,000 pounds of steel and 275 miles of wire.

“We can’t control what Mother Nature hands us, but we can learn from these events,” said Bob Dalrymple, currently Senior Vice President of Resource Management & Operations Services and Vice President of Transmission Reliability & Operations in 2011. It was inspiring to see the ingenuity, dedication and commitment to service demonstrated by TVA and local power company employees. We understand the value and peace of mind that reliable power brings and we continue to invest in smart technologies as we build the energy system of the future.”

Cullman, Alabama in the Dark

“A smaller storm early in the day was a precursor and kind of woke everyone up,” said Mike Manning, General Manager of Cullman Power Board. “Schools dismissed early and people were aware of the weather and seeking shelter.”

“We were able to shelter in a vault, but I saw the tornado approaching as I closed the door. About 3:00 p.m. an EF-4 tornado cut diagonally across the service area and knocked the whole city out. It was eerily quiet.”

Cullman suffered extensive damages with more than 200 poles damaged and miles and miles of wire on the ground. They planned to restore critical services first, and mobilized to rebuild their system to be ready when TVA was able to supply power to their substations.

“We were told to expect to be out 7-9 days,” said Manning. “But it was amazing how people came together and TVA got their system up and running faster than expected. On day three, we got 30 percent back. Working with TVA dispatch we were able to restore a little more each night and by day seven we had everyone back who was able to take power. It worked well - was piecemeal, but as quickly as possible. We also kept in constant communication with Cullman Electric Cooperative since we share some substations with them.”

The effort to keep the community informed was challenging since no one had power. They relied on morning news conferences and the FM radio station was able to stay on.

“Most of our employees had some damage to their homes and it was difficult to balance since we were working 7 days a week/18 hours a day. But the community came together to help each other and we had support from crews as far away as Indiana. The church next to our office fed 150 crew members for 10 days, and did their laundry.”

“I appreciate the good cooperation and communication with TVA. They did a yeoman’s job working with us and as smoothly as possible under the circumstances.”

Tornado Volunteers sitting on the stairs

TVA Employees Unite to Help

It didn’t take long for employees to organize efforts to support co-workers and communities.

The TVA Employee Relief Fund was established in response to employee requests to help TVA co-workers and families who suffered losses. Nearly $164,000 was donated to the fund and was distributed based on need.

Storm Clean Up Day saw 1,400 TVA employees, retirees, family and contractors spread out into communities. Eighty-one teams worked more than 11,000 volunteer hours in Alabama, Georgia, Kentucky, Mississippi, Tennessee and Virginia to clean up and restore damage from the storms.

"It was a day I’ll never forget, and an extraordinary recovery effort,” said Dalrymple. “Initially, the damage seemed overwhelming — for TVA, for LPCs, for communities and for impacted families. But we did what the Tennessee Valley does best, came together to support each other. Everyone found a way to pitch in to help their neighbors.”