Bay seniors who puzzle that Seattle, New York and Venice have on-demand water taxis and we don’t, stop your grousing. We have two of them. For Marinites (working or partying late) who miss their ferry, TidelineSF will take you from and to any authorized landing, like from Sausalito to Pier 1 in 14 minutes. The exorbitant fares run from $100 (1 passenger ) to $300 (6 passengers) and are the size of patrol boats. SF Water Taxi is a similar venture and stops in Berkeley,Marin and SF .$100 an hour.