Deep bedrock and poor soil found during preliminary drilling for the city's light rail project should lead planners to reevaluate the $2.1 billion plan, said David Jeanes, president of Transport Action in Ottawa.

"This problem is going to cause some design changes that maybe should cause them to rethink some other things too," said Jeanes.

Crews discovered deeper than expected bedrock and poor soil near the University of Ottawa that might force planners to shorten the tunnel by up to 900 metres, or almost a third of the its planned length of 3.2 kilometres running from Bronson Avenue to the university.

The problems near the university may also require the Campus stations to be built on the surface rather than underground.

Crews also found a fault line, or unstable ground, along O'Connor Street which may cause additional glitches for the light-rail plan.

"Ottawa has seen a lot of projects that have gotten into trouble because of bad soil conditions," said Jeanes. "This isn't really surprising."

Jeanes said that the city didn't give enough thought to a surface option and instead pushed forward with the tunnel project, which is taking longer than expected.

"2019 is a very long time to wait for it," he said. "Our transit problems are right now."

Councillor Stephen Blais said the complications will cause the taxpayers money if the light rail plan goes ahead.

"We've got conditions that will lead to costs," he said. "That's a huge problem for me."

Mayor Jim Watson said that it will raise concerns if the project changes but its cost don't. Still, he said he is "committed to the $2.1 billion project the previous council approved.

With a report from CTV Ottawa's John Hua