Connecting to existing sewerage and stormwater lines

Hi all,

Thanks for reading my first post on Propertychat, I'm excited to be here

I am in the process of building a granny flat for my property and am trying to get more information as the builder is not being as forthcoming as I'd like.

Background: The granny flat is to be built in Sydney and is already fully CDC (Complying Development Certificate) approved with council and all relevant authorities.

The issue I'm facing is that the builder refuses to supply plans or drawings in regards to how they will connect the main services to the granny flat (ie. sewerage, water, electricity, stormwater).

As per my understanding, this could greatly affect the costs as depending on the plans, they may need to dig up my driveway at a cost of $1k per metre (which could result in a $30k plus bill on top of existing costs).

Is it unreasonable for me to request the plans before I proceed to signing the final construction contract? (I've already signed and paid the initial contracts and fees for the design and approval stage).

Aside from this, I'm wondering if anyone knows if it's possible to piggyback off the sewerage, stormwater and pipes to the existing pipes that currently service the main house, rather than having to dig up the concrete to build new pipes? Are there any resources that anyone can point me to so I can learn about the regulations for this?

Cheers,

Stellano

 

Have you got Hunter water plans that shows where your existing sewer connection point is?

This is what they will have to tie into as you can't make a new connection without a minor works plan, has to be approved by hunter water and signed by you.

 

Sewer - possibly hook up to the existing house drainage system but a separate junction will ensure that a blockage won't affect the other house.

Stormwater - definite maybe. Does the gf require a detention pit or other connection to meet water efficiency/nabers standards or other condition imposed by council?

Water - will this have a separate meter?

 

It's Sydney water, and yes I do have these plans but I am wondering if the attached basic diagram is possible (connecting to existing pipe where the red star is, rather than digging to existing junction or creating a new junction next to main sewer).

This I am not sure. The CDC approval document set provided by the builder simply says "as required by council" but provides no further details.

No, a single utility connection.

 

Yes this should be possible.

 

Thank you all!

 

You can definitely connect both to existing.
He will need to know whether fall can be achieved before committing where connect will be made or pump system required (not ideal)
Proberly won’t know till a little further investigation.

 

For granny flats you can buy private meters to measure water usage of flat. You won’t receive a bill from SW but you can work out the usage and charge personally.

 

Yes, you can connect to your existing sewer and stormwater if you can achieve correct fall. Otherwise you will need a pump. Not recommended.
All inspections in Sydney are carried out by Fair Trading. Make sure the new sewer work is inspected by Fair Trading before backfilling the trench or pouring a slab. You will need a final inspection within 14 days after all plumbing work is completed. Get a COC (Certificate Of Compliance) from the plumber and a new SSD (Sewer Service Diagram) is submitted to Fair Trading.
‘Good luck.