I'll second FruiVita. The Riva area is now flush with hotels. Hampton, Courtyard, Residence Inn, SpringHill, and a couple more. Just about any brand you like is there. Usually there's a shuttle from the nearby (walking distance) park & ride to the city dock
There are a couple places downtown within walking distance, but expect much higher rates. Another option might be a B&B. There's a lot of those in the downtown area but, again, rates are up there.