(Published Thursday, January 20, 2005)

By Carla McCann/Gazette Staff

Kathy Brichta found out Tuesday that living along the shores of Lake Koshkonong can be an earsplitting experience.

It was early afternoon when Brichta sat down to talk on the telephone with her father. A few minutes into the conversation, her father asked if she had finally got rid of her two cockatiels. The birds usually are screeching and chirping when Brichta is on the phone.

But this time, the birds were silent.

Seconds later, a loud booming noise reverberated throughout the house.

"It was like the house was jittering," Brichta said. "I could see it."

Her first thought was that the furnace or hot water heater had exploded, because the sound appeared to have come through the floor from the basement.

Her father, who is 86, didn't hear the boom on the other end of the line.

"I didn't want to tell him what I just heard and felt," Brichta said. "So, I said 'Gee Dad, I have to go now.'"

She hung up the phone and raced downstairs to the basement, where everything was fine.

Her next thought was that a motorist must have lost control of a truck and crashed into a tree on her property.

"That definitely would cause the house to shake and tremble," Brichta said.

But nothing appeared to be amiss outside the home either.

Brichta, who moved here about 1½ years ago from Bryon, Ill., then believed the noise could have been an airplane crash-landing on the ice. She scanned the lake through binoculars, but again saw nothing out of the ordinary.

Running out of ideas, Brichta searched the attic crawl space for any signs of damage. She believed it was possible that something had gone through the roof. Again, she found nothing wrong.

Later, Brichta called the Jefferson County Sheriff's Department to ask if anyone else had reported hearing an explosion on the lake. No one did.

A deputy then visited Brichta.

"He checked all around the house," Brichta said. "He then talked with me. I know he wanted to see if I was a nut. I could tell he was observing me. I told him I work in the health care field and give out drugs, but I swear to God I've never taken any of them."

The deputy was gone when another explosion rocked Brichta's house.

But this time, her fiance was outside and saw the source of the noise. The explosions were occurring on the lake.

When miles of ice expand in different directions it can cause booming pressure releases, said Richard Lathrop, a limnologist for the Wisconsin Department of Natural Resources.

"The force of ice can be massive," Lathrop said. "We work in a concrete block building, with a boat slip in the basement, on the lakeshore. There are times when this building just shakes when ice is expanding. We hear the booming all of the time."

Ice can be heaved 20 feet to 30 feet while expanding, Lathrop said.

"This is very normal," Lathrop said.

Three ice mounds now dot the lake in front of Brichta's home.

One reason why the level of water in a lake is lowered in the fall is to allow room for winter ice expansions, without destroying shorelines, Lathrop said.

Now that Brichta knows the source of the explosive sounds, all is well at her dream home on the lake.

"I'm not a cowardly woman," Brichta said. "But I really wanted an explanation as to what could cause such a large boom and the whole cottage to shake."

As for the cockatiels, they're fine.

The birds don't appear to have suffered any lasting psychological damage from the loud noise. They still screech and chirp while Brichta talks on the phone.