Since the seventies, the carriage of oil has doubled but the number and magnitude of oil spills is down tenfold. So I agree, the evidence does not indicate that we have a bigger problem. We have a far smaller problem.
A recent study showed that since the mid-nineties, there has not been a single major spill from oil tankers or other vessels in any Canadian waters. In addition, compared to pipelines and rail, marine tanker transport has been found to result in the fewest number of accidents.