This page is to assist new and existing clients in understanding what the procedures are in completing their stormwater system and obtaining final certification. Please feel free to keep coming back to this page to understand your obligations and confirm that all steps required have been completed in order to avoid delays and costs.




1. Design Assessment/Advice Provided.


2. Fees agreement delivered.


3. Fees agreement signed.


4. Design Completed.


5. Design forwarded to client/builder once all items per fees agreement have been completed.


6. Client/Builder submit Development Application to Council.


7. Council may make correspondence to request further information or amendments to design.


8. ISC liaises with client to explain any implications of correspondence.


9. Council issues Development Consent.


10. Client AND Builder to thoroughly itemize all DA conditions, and identify each parties responsibility in order to achieve a final occupation certificate which is required prior to anyone occupying the residence on a permanent basis. It is the owners responsibility to ensure that all its contractors including the builder, landscaper, plumber etc.., to comply with all conditions relevant to their contracts.


11. Inspections are carried out during construction as required by the PCA and DA conditions, by the appropriate consultants, trades, PCA and council. The client should ensure that these inspections are carried out at each stage, as the implications of an inspection being missed can be costly to rectify.


12. If your DA consent requires certification of your stormwater drainage, then when all the stormwater elements are completed, the client is required to engage a registered surveyor to prepare a Work As Executed (WAE, or WAX) drawings.


13. Once the WAE is completed, the original, marked up in red, is to be forwarded to ISC for checking.


14. If there are no obvious faults from the WAE, than ISC will contact you to arrange a final inspection.


15. If the final inspection is satisfactory a final stormwater certificate will be issued.




Phases in Detail:


1. You can get a pre-assessment on your site, to provide you with the professional advice necessary to make an informed decision on what you construct on your property. Including what your local council impose and what alternatives are available to reduce your cost and/or improve the aesthetics. Back to Top.


2. A fixed fees agreement based on a specific scope or work will be provided. ISC's professional manner and  ethics, ensure that the designs prepared are to comply with councils policy unless stated otherwise in the scope of works. Naturally council assessments are done by council officers who may have varying opinions, which ISC will always keep a professional attitude in communications, in order to achieve the most economical design to achieve a council consent. Back to Top.


3. ISC will not commence on any design work until page 2 of the agreement is completed and returned.



4. If an OSD is part of your design, ISC will release an extract of the design to the client prior to completion in order to allow the client to provide input in the final aesthetics of the design. Back to Top.


5. Your design is then forwarded to you in electronic format if an email address is provided, or a hard copy is mailed, upon receiving confirmation of payment. Back to Top.


6. Your builder will need to co-ordinate their drawings with ISC's design where necessary, and complete any other necessary submission requirements required by your local council. Back to Top.


7. Sometimes council will reply to an application requesting further information or requesting amendments. Back to Top.


In some cases council will have records that are not on public exhibition that can affect how council will assess an application, even if full compliance has been provided in ISC's or the builder's design. Examples are existing council pipelines which run through properties without an easement. Or areas that are known to flood downstream of your property, that council is concerned about any possible increase to flooding by future development. These occurrences are rare, but they cannot be confirmed or anticipated by ISC until council a Development Application is assessed. ISC will, however, try to obtain all possible council data prior to providing a fees agreement. Back to Top.


8. ISC will liaise with the client and explain the council correspondence that relates to stormwater drainage. Any amendments required will be carried out straight away. Any design details not included in the initial scope of works will be explained to the client and either a fixed fee or hourly rate will be charged.

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9. Council is required to provide a determination on an application with 42 days. However, council can "stop the clock" by issuing a letter requesting further information. Back to Top.


10. The most common mistake by clients, is that the building procedure hasn't changed. The procedure has significantly changed in the last two years. The DA consents being issued currently have several condition now that pertain to items outside the scope of many project builders, such as driveways, landscaping, OSD, internal fittings and inspections. It is now the clients responsibility to ensure that all conditions of the consent have been completed satisfactorily, in order to obtain final occupation certificate from the PCA. Back to Top.


11. Clients should read the DA consents very carefully, and liaise with their PCA to ensure that all necessary inspections are scheduled to occur. If inspections are not scheduled by the builder, than the client should engage its own consultants to carry out the inspections with the consent of the builder to obtain access.


ISC highly recommends that you communicate with our offices during construction to ensure that the design is understood. A phone call costs 20c, but a mistake can cost $1000's. ISC is glad to help over the phone. That's our service to you. Back to Top.


Landscape Assessment

Has your PCA requested a re-assessment of your revised landscape? You can engage ISC to do so by  clicking here.



12. You've reached the final Stage - Congratulations!






Step 1. Obtain WAE - Work As Executed plans from Registered Surveyor.  Check with your builder if they have have previously prepared this before engaging surveyor.


Step 2. Engage ISC Services.  Click here .



Step 3. ISC checks WAE. Identifies any issues prior to carrying out step 4.


Step 4. ISC inspects your property. Identifies any issues prior to carrying out step 5


Step 5. Issues final account and subsequently certificate.


In Detail:


Whether you have OSD or not, you may be required to prepare a WAE (Work As Executed). Basically a surveyor takes ISC's council approved stamped drawings, and marks ALL levels, walls, pits pipes, downpipes, tanks, pumps on the drawings in RED. Please note some council like Hills Shire Council will only accept WAE done on the stamped approved drawings. Drawings issued by ISC for WAE should only be used for the purpose of obtaining quotes. Please note that not all surveyors prepare WAE's regularly, and do not complete a full WAE as noted above, and re-charge to complete as noted above.


Click here for a list of Surveyors that can prepare your WAE.  If they request copies of the drawings please email us for a copy or ask them to email us the request for a copy if you don't have them. ISC will not email drawings without written request as archive retrieval fees may apply.  Back to Top.


13. You will need to send a request via this website to engage ISC services if you haven't previously signed a fees agreement with ISC. When a signed agreement OR online request is received and the WAE is returned to ISC, it will be checked in detail that the initial design intent is still being achieved, generally within 48-72 hours after archive retrieval if required. (1/2 hour fee is applicable - $121.00incl GST). If the WAE identifies compliance is not achieved then ISC will contact the client and advise of any necessary problems that need rectification before a final inspection is carried out.

To send a request for Final Certification now Click here. (Note: A fee of $88 incl. GST is applicable to retrieve files from archives if last drawing issue date, prior to construction commencing was more then 12 months prior. )


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Once the client confirms the additional rectifications have been done, ISC will advise on whether the surveyors are required to amend the WAE or whether ISC can attend to it at the final inspection. Note: ISC does not provide project management services. The construction of the stormwater system must be carried out by qualified trades, experienced in the field. Using unqualified or inexperienced trades can prove to be very expensive to rectify errors made.


14. ISC will then arrange final inspection time based on client instructions given in the online form. Generally inspections take 1.5 to 2hrs for the Metro area. ISC's current Fees at 1-7-19 are $242/hr incl GST. Back to Top.


15. If the inspection finds any defects that were not picked up by the WAE, the client is advised to rectify them. If the items are minor and not significant to the functionality of the system certification can be issued with those items listed. If the items are not minor a re-inspection will be required. ISC's current Fees at 1-7-19 are $242 incl GST for the certificate and $242/hr incl. GST  for any re-assessment or re-inspections required (incl GST). Back to Top.


NOTE: Some councils may require what's called a Positive Covenant. It's in simple terms a legal document that is registered on the title of your property that informs future owners of the stormwater systems and their obligations to maintain it. The owners solicitor will generally arrange this registration. The wording should be obtained from council. ISC do not carry out this service. Typically councils and PCA's require the WAE and stormwater certificate before they will counter sign the positive covenenat for registration.


Charges applicable are as noted in the current terms and conditions on this website and issued clients fees agreement which are subject to change.



A List of local Surveyors


Aspect Development and Survey

Ph: 9554 8388


H. Ramsay & Co.

Ph: 9635 5840


Design Phases