Thick icicles drooping down from the ceiling created a cool sight for motorists driving through the Hwy. 5 tunnel, which passes under Hwys. 55 and 62 near Fort Snelling and the Minneapolis-St. Paul International Airport.

Drive reader Willi described the spectacle as being about a yard long and a few feet wide. He saw icicles hanging primarily over the eastbound lanes as he drove west on Hwy. 5.

"It was like going through a cave with all the stalactites," he said.

Other motorists marveled at the frozen sight, too, but like Willi they were concerned that ice spikes could fall and damage vehicles passing below.

The icicles, which formed earlier this month with the arrival of the season's first cold snap, are long gone. MnDOT took them down.

"In order to protect the traveling public, when we become aware of an icicle situation, we remove them," said Duane Green Jr., MnDOT's maintenance operation engineer in charge of structures.

But that does not mean they won't be back. Green said icicles likely formed because the original and buried waterproofing system installed when the Fort Snelling Tunnel was built in 1961 failed due to its age and the constant freeze-thaw, expansion-contraction cycles. That allows water to seep through the overhead construction joint and form icicles similar to those that grow on edges of roofs during the winter, he said.

In extremely rare occasions, MnDOT will excavate and reseal a buried construction joint. In most cases, however, the agency will recaulk the exposed side of the joint.

"Most of the time, this mitigates the situation for several years until the caulk becomes old and brittle and the water seepage begins again," Green said.

Should a motorist have the unfortunate occurrence of ice falling on their vehicle, or even hitting a pothole, and believe MnDOT is liable, they can file a claim, said spokesman David Aeikens.

To file a claim, vehicle damage must have occurred on a state highway or freeway. The condition that caused the damage must have existed long enough that MnDOT should have been notified or discovered it on its own. And MnDOT must have had a "reasonable amount of time to repair the condition or take steps to warn of the condition before we are considered negligent," according to a statement on its claims process website, dot.state.mn.us/trafficeng/tortclaims/index.html.

MnDOT is generally not at fault when hazards are caused by weather-related events and conditions such as snow, ice and flooding. It's also not responsible for damages caused by other motorists or vehicles, unreported road conditions or a driver's own negligence. Drivers who feel MnDOT is responsible for damage have 180 days to file a claim.

Ramp meters always on yellow

Drive reader Randy has noticed that meters on the ramps from Cliff Road and Hwy. 13 to northbound I-35W in Burnsville have been in flash mode for quite some time He does not miss having to wait as the lights cycle from green to yellow to red during rush hours as normal. But he wonders why they are constantly blinking yellow?

Enjoy it while you can.

MnDOT says sensors controlling the lights are being impacted by nearby construction on the I-35W Minnesota River bridge. Temporary sensors will be installed soon, so the lights will be back to normal, said spokeswoman Kirsten Klein.

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