Manage your on-site STORMWATER

Parthenon OSD - Stormwater Detention System


Precast Solution For 150,000 to 8 Million Litres

The innovative Parthenon OSD provides unrivalled versatility for projects that require large on-site detention tanks.

The Parthenon Onsite Detention System controls the stormwater runoff that is captured on your site and engineered to meet SM1600 Heavy Vehicle Impact loadings. Maximise the use of land with a unique modular design located underneath car parking areas, roads or parklands.

Specific consideration is given to the health and safety of personnel accessing each tank during inspections and maintenance. A single chamber with minimal working obstructions and trip hazards for its entire storage volume minimises the need for multiple confined space entries. 

Sediment and material obstruction removal can be accomplished by either manual extraction or vacuum extraction. As with all maintenance procedures, suitably qualified technicians following industry-regulated procedures should perform the tasks following ‘best practices’ established during job hazard analysis meetings. It should be noted that the preliminary design of The Parthenon Onsite Detention System can simplify maintenance procedures. The Parthenon Onsite Detention System can be designed with a slight grade to encourage the build-up of sediment to the downstream end of the basin.

Why choose Australian Tanks?

Our solutions are designed for small, medium, or large capacities and compete extremely favourably with alternative precast or built-on-site systems. Additionally, the lifecycle costs measure extremely well against alternatives as they are very easy to access, clean and maintain.

Every Australian Tanks system is delivered with weir walls, filtration, penetrations, trash screens, ladders, risers, manholes, drainage holes and orifice plates in place, ready for immediate install in the prepared site excavation. Importantly, all systems are pre-cured with no further waterproofing required. Installation takes place in hours, not weeks, to be connected and backfilled within the same day.

We provide tanks that are made to Australian Standards to allow for restricted heavy vehicle access based:

  • Heavy duty construction rated for where the heaviest vehicle traffic will be a 4 axle twin steer truck eg. garbage truck.
  • Un-restricted traffic loading in accordance with AS5100 can be provided with further engineering for your needs.

Our range of tanks are easily interconnected in multiples to create any volume quickly and cost effectively. Every system is certifiable, with increasing numbers of engineers incorporating our systems into their designs due to the structural integrity and multiple efficiencies of our service.

Our products are easily modified to fit the volume required on your project. Along with other on-site parameters we can create the ideal custom solution for you and your team.


a cost effective solution for large scale requirements

Underground stormwater detention is a common application for The Parthenon Onsite Detention System and is well regarded as the solution to meeting legislative requirements for onsite detention without compromising the delivery of high-yield useable land area. The benefits of pre-casting such systems are many-fold and include;

The Parthenon Onsite Detention System has been designed to maximize the desired outcomes of safety-in-design with respect to manufacture, installation and life-cycle maintenance.

The standard Parthenon tank unit is exceptionally versatile and can be further augmented to facilitate other key functions related to the management of stormwater runoff. The entire range of Australian Tanks can be added to suit any requirement.

Filtration Units can be added to the system or additional self-contained Tank Units can be added to house pollutant filtration and removal.

Sediment Fore Bays can be configured into the system to localize the sediment in one area.

Infiltration Openings can be designed into the base panels to allow discharge of the stormwater runoff via soil.

Stormwater Quality Improvement Devices (SQIDs) can be either located upstream, downstream or internally to the system to the system to complete the requirements of the stormwater quality and quantity management plan for the site.

The standard detention tank system can be augmented to facilitate capture and retention of stormwater runoff for harvesting and re-use. The Parthenon can be linked to a range of other water holding tanks from Australian Tanks to fit a range of water holding and detention

Self-Cleansing internal pipework can be included within the tank to allow flushing of the system without the need for confined space entry.

Why Choose Pre Cast Over 'Block and Slab'

Traditionally, OSD installers have heavily relied on ‘block and slab’ solutions to build OSD tanks and systems.

As the necessity for OSD systems has increased, so too has the reliance on those traditional labour and time-intensive block and slab detention tanks.

And, as with all demand increases, the costs have increased for slab work, block walls, suspended roofing and waterproofing.

More importantly the on site occupational health and safety requirements have made it more onerous for builders and contractors – this has also lead to increasing costs as well as the need for considerably more manpower and paperwork for Project Managers on site.

Builders and contractors are fast becoming busier in the ever-growing markets of Sydney, Melbourne, Brisbane and the Gold Coast – time becomes a major asset and lost time costs big money. Open excavations, delayed contractors, bad weather Australia regularly experiences, and the need to find additional components for block and slab systems can all combine to negatively impact building costs and efficiencies.


We pride ourselves on our service

Australian Tanks could never have grown to where it is now without our valued customers. Our attention to detail is why our customers keep returning to solve their water storage solutions. We want nothing more than for our customers to enjoy the longevity and efficiency of our commercial water tank solutions, which is why we work as closely with our customers as possible to find the best solution. Check out some of the things our favourite customers have said about us!

Nick Rees
Context Engineering
Australian Tanks products are easy to specify on a drawing – they’re easy to size, and are workable within most site constraints.
Bruce Rob
Group General Manager
HWB Group
Thanks to the team at Australian Tanks for getting this key piece of site infrastructure in place in such a short space of time despite rain and allowing the site access back in use quickly. Well done to our BUILDUS team for getting on with the job.
Adam Williams
Managing Director
Platinum Hydraulic Design
The professional manner in which Australian Tanks approached this project resulted with the successful installation of several large capacity grease interceptor traps that are fully compliant with the City of Gold Coast Trade Waste Department requirements. Congratulations to Les Green and Team for the professionalism, and a quality product.
Aaron Glowka
Project Manager
The service from the team is outstanding, they’re always available to help. They’ll do whatever they can including come out and work you to get it right. The different volume tanks are brilliant! Standard sizing that you can adjust the volume makes it uniform when working across different jobs. Consistency in area for planning also helps to save time and money in the long run!

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