New York City Mayor Bill de Blasio announced Thursday plans to expand ferry service in the coming years.

De Blasio plans to increase funds for the service, hoping to carry as many as 9 million passengers by 2023.

He added that the program has grown faster than anyone expected.

"We're going to be doubling the size of our fleet and there's going to be a lot more of the bigger boats," said de Blasio. "Which will allow us to get a lot more people where they are going and reduce the waits, reduce the lines. We're also going to be improving the piers and the docks so the people can get on and off the boats more easily."

NYC Ferry launched last year and serves routes in four boroughs for a $2.75 one-way ticket.