Where is the closest swimming pool to The Vines?

I wouldn't bother with the State Swim pool in Ellenbrook. It's expensive, the staff are extremely rude and they are only open 45min in the morning and 2hrs in the afternoon. They are also closed during all school holidays.
Your best bets are Swan Aquatic Centre in Midland and Altone Park in Beechboro.

There is one at the Novotel The Vines Resort - however you have to be a club member to use it. Ellenbrook has a State Swim swimming pool close to the library in the centre of town.