"It may have been lightning, or a damaged lightning arrestor that just failed," said General Manager Mark Dahlberg of Northwestern Wisconsin Electric Co. explaining an outage that covered a huge area and lasted up to an hour and 35 minutes Thursday night.

"We knew the trouble was at Rock Creek and Hoffman sub-stations," said Dahlberg. "We had a 69,000 volt line that would not stay on," he said.

At Rock Creek an employee was able to look at the relay and tell where the fault was occurring. "It was 3.8 miles east of the Rock Creek sub-station," said Dahlberg, adding, "Right at the St. Croix River."

Because the line goes under the river, Dahlberg said, "Let's face it, this was scary."

But fortunately the problem was a lightning arrestor on a pole and once a new one was retrieved and installed, the problem was corrected.

"Two linemen looked at the terminator poles and on the east pole they found a blown 69 KV lightening arrestor that had really failed. That prevented the line from being closed, and caused the outage," said Dahlberg.

The outage was extensive, from Dairyland through Grantsburg.

"We're connected with a 230,000 transmission line from Duluth to Stillwater that serves Grantsburg, Alpha, Wood Lake, Falun, Penta, Clam River Dam and Siren," Dahlberg said.

Dispatchers got to Frederic dispatch center. We had four crews out.

Siren, Penta and Falun were the first to have their service resumed. "Then came Alpha and Wood Lake and finally Grantsburg, the Hoffman sub-station and Dairyland.

"Parts of Webster were also out, particularly north of Siren, but the village of Webster was not affected.

"We're fairly normal now," Dahlberg said Friday afternoon.

But he said, "There is a debate on whether this was caused by lightning in the area or it may have been an arrestor damaged at another time that just decided to fail. We're not sure. I know there was lightning in the northeast, because I saw it," he said.