Well the local flat water venue is called "Glory Holes"! For good reason, one of the locals has managed 40kts there
An hour up the road is Mandurah, with lots of great flat water spots, and gets better wind than Bunbury a lot of the time.
We do a lot of speed sailing here.
Binningup has small to medium waves in Summer, Avalon can have nice down the line waves in a seabreeze, but doesn't get a lot of swell in Summer, and it needs about a 2m swell.

Koombanna Bay is the current foiling venue of choice,

I'm a local. We don't get the wind that Perth does, but still get our fair share of good days. I'm into speed sailing so I sail at Australind, or an hours drive and you can be up at the Mandurah speed spots. I used to pretend to wave sail at Binningup, 20min up the road. Great fun, but then I got paranoid about sharks.
Windfoiling is also becoming popular at Koombana Bay.

So are you moving over here Hermun?

Hermun said..
Not just yet. Maybe next year. Living in NZ at the moment but planning a move westwards next year. Either here or South Australia. Thanks for all the info. I spotted the lagoon on the map but you can never be sure of the water depth from maps and risk running aground. I'll keep you guys informed.

You can certainly run aground if you don't avoid the sand banks

Go to Lake George (Beachport) and become a speed addict