FirstEnergy Corp.’s transmission lines subsidiary is seeking permission from state regulators to restring electric power lines along a 29-mile section of its power grid that spans southern Lucas and northern Wood and Henry counties.

American Transmission Systems made its request to the Ohio Power Siting Board this month and hopes to receive approval for the $14.6 million project in time to start work by May 22. The subsidiary hopes to complete the work by Dec. 1.

The 138-kilovolt grid section is known as the Lemoyne-Midway and the Lemoyne-Dowling transmission line. It starts at an existing Toledo Edison substation in the community of Lemoyne in Wood County and extends west to a substation in the Wood County community of Dowling.

From there, it continues west through southern Lucas County and into Henry County to Edison’s Midway substation near Liberty Center.

Christopher Eck, a FirstEn- ergy spokesman, said a rewiring of the grid section is needed because the utility has closed several power plants, including all but one generating unit at the Bayshore Power Plant in Oregon, requiring it to send power from other electric plants over longer distances.

When a utility sends power — or “wheels” electricity — over farther distances, transmission wires can heat up, causing them to stretch and sag. The problem also occurs during rising outside temperatures in the summer.

In 2003, wires owned by FirstEnergy overheated, sagged, and brushed a tree in northeast Ohio, putting into motion a chain of events that led to the largest blackout in North American history.

The 29-mile Lemoyne-Dowling lines date to 1972 when that grid section was built. American Transmission said a recent inspection of the line revealed that some parts have become corroded past acceptable limits that have put the line at risk for failure.

“The new lines will have a higher heat tolerance in accordance with a higher [power] load,” Mr. Eck said. “Basically, what it does is it improves reliability.”

Because it already has easements, American Transmission won’t need to seek land or permission from landowners to rewire the grid line. The subsidiary will replace three wooden poles plus a steel tower along the route, the proposal said. Several other structures along the route will be reinforced.

Contact Jon Chavez at: jchavez@theblade.com or 419-724-6128.

First Published April 29, 2017, 4:00 a.m.