Rathgar Lodge

Consultancy and assessment

Engineering and planning consultants Ardill Payne & Partners engaged True Water on behalf of Rathgar Lodge. We began by inspecting the existing wastewater treatment system at the lodge. Although in generally fair condition, there were signs of overloading, ageing, and poor treatment quality. The disposal or land application area showed various signs of disrepair and damage. The expansion of the lodge was then postponed, however the need to remedy the treatment system issues had been identified.

The next task was to assess the flow rates produced by the lodge each day. Correct flow rates are critical for correct system sizing. Once known, attention was placed on addressing all other important criteria.

Important items to consider include:

• Space – limited for the disposal area of a larger system.
• Location – proximity to the river and in a flood zone.
• Residential – no noise or odour.
• Visual – aesthetically pleasing for the residents.
• Scalable – expansion still planned for the future.

A realistic and viable solution was found after consulting with Ardill Payne and Rathgar Lodge. The upgrade to the system and disposal area were to be staged. No interruption to the every day running of the lodge would be caused during construction. It also allowed for the gradual expansion of the system in line with the expansion of the lodge in general. Expansion could be timed to suit the needs of the lodge and to stage financial outlay.

New wastewater management system for the Aged Care Facility

A 10kL Kubota HC-Z sewage treatment plant was chosen as the best system for the first stage. The HC-Z is a compact system that treats to a high level. It sits below ground after installation, producing a very low visual impact. Because it is sealed, there is no noise or odour impact for the residents at all.

The decision was made to decommission the old land application area. Poorly treated water, age and damage had deemed it unviable to resurrect. True Water designed the new disposal area to suit the site’s restrictions which include limited available area, proximity to the river and below flood levels. The solution is an engineered effluent disposal system that is situated in a grassed area beside the lodge.

The specially designed disposal system solved various problems. The slightly raised area is engineered to allow all effluent dispersal to remain above water if the river ever flooded. This allows the lodge to continue to operate without a failing system. This solutions also occupies a much smaller footprint than other disposal methods. The limited space for disposal will now be sufficient, even with the future expansion plans. The design and construction are also very durable giving operational security long into the future.

The engineered effluent disposal system is sized to take the additional load when the lodge is expanded in the future. The high treatment level of the Kubota system also gives the disposal system a much easier job than with poorly treated water. The area was turfed after installation for effectiveness and aesthetics, with the area now blending in gently within the landscaping.

State of the Art Wastewater Solutions for Current Regulations

The site specific requirements of providing sewage management for commercial properties that are not connected to municipal sewage infrastructure can sometimes be tricky. Importantly, Ardill Payne realised the challenge when they first assessed the site and called in True Water as specialists in the field. Although the existing system was undersized and in poor repair, any replacement had to meet current regulations. Many modern regulations stipulate much higher standards than the original system could ever achieve. Flood zones, soil types, space and treatment levels all added to the challenge at Rathgar Lodge.

Modern problems can be solved with modern solutions. Kubota has spent many years refining and improving their systems. The result is a deceptively simple system created by intelligent design and engineering. It is a compact system with high treatment levels and excellent reliability and durability. A complete solution is achieved when the Kubota is part of correctly designed and installed infrastructure. In this instance, the engineered effluent disposal system was an integral part of the complete solution.

Planning for the Future – Staging the Infrastructure Delivery and Costs

Plans are now in place to install a second Kubota system at the lodge. It will be a 10kL HC-Z exactly the same as the first one. Connecting the systems is very simple and was already considered in the initial design. The last of the old system can be completely decommissioned after installation. This will remove any weak points and greatly reduce maintenance. The effluent disposal system is already sized for extra loading so the upgraded system will be complete. The expansion of the accommodation can then take place.

True Water, Ardill Payne & Partners and Rathgar Lodge worked together to find a solution. Knowledge and expertise combined with the latest technology means that all criteria were successfully addressed. The lodge has an appropriately sized system with much lower operational and maintenance costs. Operational security has been vastly increased, and the concerns of the residents and the environment have been met.