Canadian National Rail spokeswoman Emily Hamer told the Associated Press Sunday that a downpour in the area of Burnaby, British Columbia, caused a beaver dam to wash out, which in turn caused water to pour over a set of tracks and ultimately led to a seven-car derailment Saturday.

No one was injured in the 11am incident, which involved a 152-car Canadian Pacific Rail line.

Two crew members aboard the train also escaped unscathed.

Four of the derailed cars remained upright, but three overturned cars sent cola into a creek that feeds Burnaby Lake. Officials are still determining how many tons sunk into the waterway.

In the wake of the derailment, environmentalists questioned the rail track’s maintenance.

“Given that heavy rains were widely forecast for this weekend, this calls into question how closely CN is monitoring the safety status of rail lines used by heavy and long coal trains," Voters Taking Action on Climate Change said.

“If you're going to move more coal trains, there has to be a corresponding increase in vigilance.”

CN responded by telling local media that it does increase monitoring when heavy rains are forecast.

“We did track inspection very recently — within the last couple of days,” Hamer said.

“We do very regular track inspections for the safety of our crews and the communities they run through.”