There is a fast boat from connexxion connecting Amsterdam Central Station and Velsen-Zuid, Pontplein. The fast boat is travelling along the noordzeekanaal every 30 minutes on weekdays and every hour in weekends.
See the website for more search for fast flying ferry.
The green hydrofoil of Fast Flying Ferries races at speed between the centre of Amsterdam and Velsen. These craft are quite a site racing past you if your on a cross river ferry, however don't stand too close to the front of the ferry when one shoots by or you will get wet when their bow wave hits. Within a half hour these boats bring you from Amsterdam Central Station to the Pontplein in Velzen-Zuid. Its € 4.95 for a one way ticket. Strangely enough dogs go free one way but cost € 2.75 for a return ticket.
I suspect a lot of feral dogs in Velsen!
This is an exellent service. We used the Hydrofoil ferry in March and will definitely be using it again. Velson to Amsterdam Centaal Took 25 - 30 mins @ 8e for a return ticket. comfortable and cheap 10 / 10