CHICAGO (CBS) — Less than two months after the first section of the Navy Pier Flyover opened along the lakefront, the long-delayed pedestrian and bicycle bridge already is showing surprising signs of wear and tear.

The much-anticipated project has taken longer to build than the Golden Gate Bridge, and it’s still not finished. But the section that opened in December already is showing signs of trouble before the rest of the project is completed.

A shiny new bridge that lifts cyclists and runners over traffic on Grand Avenue and Illinois Street opened a few days before Christmas.

Chicago Mayor Rahm Emanuel said the project would “stand the test of time,” but less than two months later, sections of the trail have cracked, markers denoting the different sections for runners and cyclists have faded, lane dividers are missing, and rusted nails are protruding in spots.

Few people use the path in the winter, so overuse can’t be the problem so soon after the trail opened. For some of the markings, a simple touch can peel away the paint.

“If there’s no lane markings, it’s going to cause a lot of confusion,” said Aaron Duncan, who speaks from experience.

Duncan collided with a rented quad bicycle a few hundred feet past the flyover last summer.

“I hit my head on the pavement, almost broke my arm,” he said. “My biggest concern is that when the tourists are walking up and down the walkway, they’re going to have no idea where to be walking, which side to be on, and it’s going to get dangerous and crowded.”

The Chicago Department of Transportation acknowledged the Navy Pier Flyover paint did not hold up this winter, and promised to fix it when the weather improves. A spokesperson also said the opened portion of the flyover is a “temporary structure.”

While CDOT Commissioner Rebekah Scheinfeld called the first phase of the flyover a “major milestone” in December, a spokesperson said that referred to the separation of path users from cars.

The entire Navy Pier Flyover isn’t expected to be completed until 2020 at the earliest. Construction began in 2014, and originally was supposed to be completed in 2018, but the city said repairs needed on the seawall and the existing Lake Shore Drive Bridge delayed construction of the flyover.