CHICAGO (CBS) — It must be spring. The city’s tour boats are back along the Chicago River and Navy Pier.

Friday was Shoreline Sightseeing’s first full weekday in operation this year. Port engineer Chad Rice has gone over the internal systems of each boat, stem to stern.

“Mechanically, it’s a combination of going through all the marine systems, testing all the batteries, checking all the electrical connections. We start there, then mechanically we go through the drive lines, and make sure shafts are tight; everything from the shaft line back is all tightened,” he said.

As the pilot guided the Evening Star down the Chicago River, Shoreline docent Kevin Burrows explained the city and its architecture in his own way.

“I like to end my tour with a little harmonica blues,” he said.

Only 17 people were aboard the Evening Star’s first cruise of the day, but Burrows – who has a bachelor’s degree in theater, and a master’s in film – acted as if he had a full house.

“The skyscrapers were built by workers, and here’s just a tidbit. How did those workers get to Chicago? They hopped freight trains, because there were 3,000 miles of tracks right here in Chicago, and our very own Halsted and Madison was the hobo capital of America,” he told his charges as they floated along the river.