If you've spent time driving around the national park, you've probably encountered a strange one-lane bridge over a stream. Traffic lights on each end alternate in a cycle that lasts several minutes: first westbound traffic is allowed through for a while, then eastbound. It's a slow process that results in lengthy delays, and could be vulnerable to floods.
The reason for the bottleneck is a landslide that occurred five years ago on Highway 140. With the highway blocked, engineers had to act fast to install a temporary solution. But a longer-term fix has proven more difficult.
They could bring a cement bridge, but that's clearly inappropriate for a national park since it would spoil the natural surroundings.
Or they could install two viaducts, but that would destroy a wildflower area.
Or they could tunnel under the landslide, but there's a rare salamander living in that area and construction would wipe it out.
And then there's one last option: just keep it the way it is and cross your fingers that it doesn't fall over or wash out.