Drought hits TVA power production

"I don't know anything about global warming," Gene Gibson said at a weekly meeting of the Chattanooga Engineers Club in response to an attendee's question. "We just keep praying for rain." Eliciting gasps, whistles and scattered exclamations from club members packing the Tallan Cellar restaurant's dining room for the lunchtime talk, Mr. Gibson clicked through his PowerPoint presentation, describing in detail how the region's yearlong drought has affected the Tennessee River system.

The Tennessee Valley Authority has kept the system at "minimum flows" since February, allowing just enough water through dams and locks to maintain water quality, navigation and recreation requirements, Mr. Gibson said. Nonetheless, TVA has had to rely on more power generation from alternate sources this year, he said.

Minimum flows have cut normal hydroelectric power generation nearly in half, while warmer-than-normal reservoirs are threatening to curb or even halt production at nuclear and fossil fuel plants, Mr. Gibson said. "We're getting very close to the limits," he said. "It's something that everyone at TVA is very concerned about."

But even if plants continue to run normally, consumers may notice an increase in their electric bills, a TVA spokesman said.

Gil Francis said TVA's "fuel-cost adjustment" changes quarterly to reflect the past quarter's business, so lower hydroelectric power generation this summer could raise electric rates in the fall.

"When (hydroelectric) production is down, you have to go to other (forms of) generation, and whatever you go to, it's going to be more expensive," Mr. Francis said. "Valley consumers will eventually pay for that." The Chattanooga area remains in an "exceptional" drought, according to the latest U.S. Drought Monitor report, posted July 17. The National Weather Service reported that only 17.75 inches of rain have been recorded at Lovell Field since the begin ing of the year, slightly more than half of the expected 32.53 inches.

However, as of July 22, Chattanooga has received an above-average 3.76 inches of rain in July, and the weather service's latest Seasonal Drought Outlook calls for "some improvement" in the dry conditions for the period through October.

"At this point, we're so far behind for the year it might take two tropical systems that produce a widespread heavy rain to really turn things around," said David Gaffin, a forecaster with the weather service office in Morristown, Tenn. "We're still expecting an active hurricane season.... We'll just have to wait and see."