I have a second hand spa that I've purchased from Marketplace which I am going to half recess in the ground, with a small deck built around it.
The spa is 2m x 2m and the hole will be about 500mm deep.
Do I need to consider any drainage or retaining wall?
Consult your local council. They might provide a free development advisory service.
my local council fobbed off any planning work to independent private companies.
I asked about moving a fixed garage on my property (shifting the garage backwards 3 metres). the council person couldn't tell me anything. couldn't even refer me to anyone in the office as that sort of work work had been tendered out.
I approached one of the listed planners provided by the council and that person said it would be $700 to consider my proposal - literally I asked "I have fixed single car garage. can I move it backwards 3 metres?".
My condolences..
I dislike the move to private certifiers. However regardless of who provides the advice, in this case there are probably plenty of considerations of that move, like closeness to boundaries, easements, etc.
What does your planning permit require?
Why would I need a planning permit to dig a hole…
For the spa, not the hole. You will need fencing around your sunken spa in Victoria and a permit as well as regular future inspections.
I'm aware. This question isn't asking about the legalities/permits required for a spa though, but thanks for your concern and helpful answer.
Once again, this question wasn't asking about what approvals I need.
I never said it was…
I'm just "sharing my thoughts!" as requested in the Comments field….
I asked about a retaining wall/drainage, not permits, so a bit of an irrelevant response.
See if you can locate the specs sheet online if it didn’t come with one.
Requirements for drainage and retaining will both depend a lot of what your soil is like. Only an engineer can provide a decent answer.
"It is critical that you allow for a drainage pit" - Also the pit needs a retaining wall or it may collapse in itself when soil profile wets out.
https://www.spaworld.com.au/learn/installing-deck-or-pit-for…
Note - this is for installing a portable spa in-ground: if Your spa is an factory-built in-ground spa then you will need to adhere to the manufacturers installation instructions.
I think you'll need a permit from council to dig the hole OP
You'll need to consider drainage of the spa itself for when you want to empty it. Mine is a turn plug, so you need to consider access too that. Whilst you might not do it often, you need to have it in mind.
I empty mine every winter and we only use it during the summer time. Winter is just too cold outside (In VIC).
I have a pump that I would use when needed.
Sounds like a lot of effort when pumping 1,000 litres.
Your kidding right?
It pumps 7000 liters an hour. Will take 10 minutes to empty the spa using the pump.
Get the Pump > Start the pump > make sure it drains correctly and gets it all without a hassle and avoid not stuffing pump
vs
Pull the plug out of the bottom side of the Spa and leave it, no need to worry about pump.
I know which one I would choose.
This second hand spa might turn out to be a very expensive spa at the end of it.
What water will get into the hole? Just rain or run off too? What are you putting on the base or the hole and what is the drainage like in your area?
You need somehow for the water to get out. Youll probably need some form of wall to stop the sides caving in.
Consult your local council. They might provide a free development advisory service you can use to see what you need to do.