Subdividing land can be a difficult process with many complications and site constraints.
We frequently receive questions including:
- What is the subdivision process?
- How much does it cost per lot for a subdivision?
- What are councils infrastructure charges?
- What is Councils application fees for subdivisions?
- How many lots can I yield when subdividing my site?
In this article Development Project Manager – Registered Architect Dan Everett from EVERETT Property Development Management chats with Directors and Civil Engineers of Wilkinson Shaw & Associates, Steven and Kym Wilkinson about their experience and challenges with subdivisions. This article looks into what Civil Engineers do in the process of a subdivision and explores the subdivision process for undertaking a reconfiguration of lot (ROL) development in South East Queensland (SEQ).
CHANGE OF CIVIL ENGINEERING OVER THE YEARS
Civil engineering has evolved over the last few decades. While the guiding principals that were used are basically unchanged the way in which we attack our workflow has dramatically changed. Slide rulers have been updated by calculators and spreadsheets and drafting boards have been made almost obsolete with the introduction of computer aided design (CAD) and drafting packages. Our last design that used hand drafting was undertaken in 2006 and it was only approximately 2 years ago that we finally retired the old drafting board, tracing paper and scalpels. For those that never ventured onto a drawing board, a scalpel was used to scratch out a mistake.
As time has progressed the involvement of a civil engineer in the development industry has become more regulated. While some documents have basically remained unchanged, apart for some updating for environmental consideration, the way the regulators apply these documents has become less flexible. Go back not even 10 years ago and major design changes that were undertaken on the fly during construction would be addressed via the “as constructed drawings” and certification. These days we are lodging Generally In Accordance With (GIW), stopping construction and waiting for approvals to ensure that the authority doesn’t reject the changes.
Have you seen a newly completed development and wondered what the whole at the lowest end of site is for? It is now standard practice to have stormwater quality and quantity devices, such as wetlands, bio-retention basins and detention basins in a subdivision with more than 6 lots or 2,500m2. This requirement has eventuated due to an increase awareness of our environment that has evolved over the last 15 years. The awareness has been incorporated into the Environmental Protection Act via different mechanisms, but the main trigger is the State Planning Policy.
Mentioned previously was as constructed drawings, oh how the requirements have changed! Once upon a time, the majority of our as constructed drawings were undertaken as “mark ups” on the design plans. Then slowly we started providing details of exact locations of manholes and other structures via offsets from RP boundaries along with the mark ups. Move forward a little further and we are reproducing stormwater long sections, including the analysis, within the as constructed drawings. At this stage we are submitting the drawing on paper and microfilm!
Out comes the next advancement – PDF. Council’s start to allow electronic submissions of the as constructed drawings. This is a huge win and time saver for everyone. Then with a couple of steps along the way the as constructed process further evolved to include ADAC, or As Designed As Constructed, documentation. This was meant to be the messiah of as constructed documentation. There was to be no more mark ups, no more PDF electronic signatures and a 3d special representation of all infrastructure would be available to the regulatory bodies. But alas it hasn’t eventuated as proclaimed and now the majority of Council’s and Authorities request ADAC in addition to electronic mark ups!
Technological advances have altered the way we inject data within our designs and how we release our final deliverables on a project. Surveys are provided with a 3D terrain and service models that are spatially located. We are then able to design directly over the top of this information and in some instances this information is then sent via the cloud to a contractor in the field to undertake the construction from our design model. Progressive earthworks quantities can be quickly evaluated using a drone and photogrammetry software without the need for a surveyor on site. By using this technology, a site can become effectively “pegless” once the initial site control has been undertaken by a surveyor. The surveyor can then be called in to “pick up” the required as constructed information and peg the lots once the chances of the pegs being dislodged is minimised.
WHAT DO CIVIL ENGINEERS DO?
For a reconfiguration of lot (ROL) development application / subdivision.
- Site serviceability due diligence
- Developable area investigations
- Civil design
- Urban design
- Roadwork design
- Stormwater systems
- Stormwater management
- Sewerage systems
- Water reticulation
- Inspections of contractors work during construction
WHY PICK UP THE PHONE TO A CIVIL ENGINEER PRIOR TO SIGNING A SALES CONTRACT?
Wilkinson Shaw & Associates as civil engineers with years of experience with subdividing land, have a good grasp of minimum lots sizes, minimum frontages and average block widths and can give you an indication of your expected lot yield. What civil engineers can also do, that generally a town planner or surveyor can’t, is tell you which engineering issues are going to stop your project before it even starts. There are 3 engineering requirements for a subdivision to occur:
- A connection point for sewer;
- A connection point for water; and
- A lawful point of discharge for stormwater
In addition to the big three, a civil engineer can also help identify areas of risk or constraints such as steep slopes, flooding or traffic requirements that may require further investigation by other specialists. It is also possible for a civil engineer to provide you with an indicative construction budget on your project. It should be noted that this can entail a lot of work when there isn’t a design available and the contingencies may be large.
THE PROCESS TO A SUCCESSFUL SUBDIVISION
The first step in a successful subdivision development is the appointment of the project team members; development manager and a civil engineer to assist with the feasibility study.
We have included items that EVERETT Property Development Management includes in their feasibility studies below.
- Due diligence
- Market research
- Town planning assessment
- Site serviceability study
- Highest and best use study
- Yield study
- Project program
- Detailed feasibility investigation
How can a civil engineer and development manager assist during the feasibility phase?
Civil Engineer – Assist with investigations into yield and site serviceability of the lots.
Development Manager – Assist with coordinating the Feasibility Study
- Development Application (DA)
Contact Dan Everett and Steven and Kym Wilkinson to discuss the subdivision process after the feasibility study
- Engineering Design / Operational Works (OPW)
- Construction (Including Tender + Marketing)
- Plan Sealing, Titles and Sales
Case Study 1 – Park Ridge
We were undertaking the design and construction supervision of a repeat client’s project (Developer A) when the neighbouring upstream developer (Developer B) had to obtain stormwater discharge approval. Over months of design checks and meetings, a satisfactory discharge arrangement from the proposed detention dam was agreed and both parties commenced construction of the first stage of their developments.
As the first stage of construction for Developer B came towards the end, we were approached to provide a quote on Stage 2. The layout had changed significantly, and we were provided with a layout plan that contained:
- 29 lots
- Combined detention and bio-retention basin.
We put forward to Developer B that we would be able to remove the detention component of the layout and possibly remove the bio-retention component as well. Worst case scenario was a yield increase of 2 lots. Developer B told us that their current consultant said they couldn’t remove either detention or bio-retention. Our tender was accepted and we moved into helping the Planner’s lodge a negotiated decision notice (NDN).
The NDN amended conditions that were unclear or not required by the Planning Scheme. We undertook a detailed stormwater management report and capacity assessment based on the detention allowed for as part of Stage 1 of the development. The outcome was that we had to upgrade a small section of pipe at the upstream end of Stage 1 due to a redirection of the assumed catchment and NOT provided detention or bio-retention.
In the end our Client ended up with:
- 33 lots (increase of 4 lots or almost 14% yield)
- No detention or bioretention.
- Construction cost savings
Spending a little bit of extra money to undertake a more detailed analysis and report can result in a huge return on the investment!
Case Study 2 – Importance of early service locations
A philosophy that we adopt at WSA is to ask for potholing and location of critical service prior to commencing design. This can be difficult to obtain as the surveyors are unable to locate underground services that don’t have manholes or access chambers. Gas requires extreme caution when potholing, watermains are often through intersections and communication blocks can be encased in concrete.
We have been engaged on numerous projects to find a solution when service locations were not confirmed prior to undertaking detailed design. It is standard industry practice for the civil contractor to confirm the location of services prior to construction but this is often too late. If a service clash is detected once the contract has been commenced there is the possibility for costly delays for all parties while the designers attempted to find a solution around the services.
A recent example of this is a residential subdivision in Ipswich City Council. We have been engaged by the Principal Civil Contractor to try and minimise the delays experienced on the project due to the services not being located prior to design. Currently this project has been delayed in excess of 6 months due to design changes, reapprovals and relocation of services. Leaving location of services as the contractor’s responsibility is often too late for design purposes.
Developers also need to be aware that there is an increase in density of services located around schools, hospitals, telephone exchanges and major intersections. Prior to entering into a sales contract, we would advise undertaking a Dial Before You Dig at an absolute minimum. Also talk to both your civil and electrical engineer to determine if these existing services could be problematic.
TAKE AWAY FOR CONSULTANTS
- Call your civil engineer at the beginning of a project. They can help you identify key concerns and constraints early.
- Get the entire design team engaged and COMMUNICATING early. We can’t do our best work if we work in isolation!
- Invite your engineer to pre-lodgement meetings.
- Ask your client for the feasibility study. If they don’t have a feasibility study engage with a development project manager and assist with the cost items of the feasibility study.
TAKE AWAY FOR DEVELOPERS / LAND OWNERS
- As a developer you need to be extremely careful of what each proposal is incorporating and be warned that going with the cheapest price can often cost you a lot more than the difference in fees. If you are in doubt on what is included ASK and if you don’t like the response RUN!
- The big 3 – sewer, water and stormwater connections. If the connection point isn’t in your property it could cause problems.
- It can be more cost effective to engage a civil engineer before signing a contract. A small upfront fee may stop you from making a poor purchase.
- Spending a little bit of extra money to undertake a more detailed analysis and report could result in a huge return on the investment!
- Engage with your development project manager early and before acquiring a site to assist with site due diligence and the feasibility study.
- Logan City Council
- Redland City Council
- Brisbane City Council
- Ipswich City Council
- Moreton Bay Regional Council
- Gold Coast City Council