Waterside is a direct and easy 20-minute drive from the CBD. There is ample free parking right next door at the Port Adelaide TAFE.
Route 150, Stop 41 lets you out at the British Hotel on the corner of Nile Street. Timetable here: https://www.adelaidemetro.com.au/routes/150
Routes 117, 118, 230, 232, 252 and 254 also stop in Port Adelaide – for more details visit: https://www.adelaidemetro.com.au/timetables/buses
The Outer Harbour line, Port Adelaide station lets you out with a 10 minute walk to Waterside.
View the train timetable here: https://www.adelaidemetro.com.au/routes/OUTHA
Taxi fare is approx $25-35 to the Adelaide CBD.