Richmond tunnel maintenance uncovers big structural problem


It was supposed to be a cosmetic job to cover up water leaks that are seeping through the tunnel walls, but when a piece of concrete broke away and a construction worker looked inside the hole, he realized they had a much bigger problem on their hands.

The concrete walls of Richmond's Dornan Tunnel have been holding back the earth for 101 years, but a piece of the tunnel ceiling broke away on Friday, revealing an alarming discovery.

"There was actually a large air void inside, above the tunnel," said Melissa Tigbao, a Richmond staff engineer.

Tigbao says it is a space about the size of a pickup truck that should have been filled with earth pressed against a concrete wall two feet thick.

"What was disturbing is that the ceiling of the tunnel was really only about five inches thick of concrete that's not reinforced," said Tigbao.

The city's indoor pool, The Plunge, has been at the entrance of the tunnel since 1926.

"Coming into town to the Plunge, I have to take a little detour. But it's not serious," said swimmer Norm Hantzsche.

But getting to the other side could affect the pool's upcoming open water swim to benefit youth swimming in Richmond.

"It would be possible that if the tunnel wasn't open buy then that it could make it more difficult. We may not see as many swimmers as we would hope," said John Schonder, the Richmond Swims coach.

The real inconvenience could be the cost to tax payers. A $750,000 cosmetic job will likely reach into the millions and it could climb even higher if they find more of those dangerous pockets above the tunnel.

"I wouldn't be surprised. I wouldn't be surprised if there were more voids," said Tigbao.

The next step is to use a radar device to look through the tunnel walls and see if this project is going to cost the city more time and more money.

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