Table 5 - Water Body Parameters by Category Chart

Filtration vessels shall be designed and constructed in accordance with the following requirements:

·        To achieve a uniform flow of water through the filter bed.

·        To be capable of withstanding normal and continuous use without deterioration that could affect the filter or filter operation.

·        To permit regular inspection and maintenance.

·        To permit adequate and effective cleaning or replacement of the media, to achieve design flow rates in filter and backwash mode.

·        To have corrosion-resistant components.

·        Where filter vessels permit the accumulation of air in the top of the vessel housing, the filter vessel shall be equipped with an air release system, which evacuates the air automatically.

·        To be installed with all necessary pressure gauges and instrumentation.

·        To be clearly labelled with model, make, filter area, pressure rating and flow rates (in filter and backwash mode).

Other Requirements
Facilities shall comply with the following requirements:

·        Water velocity in pipe work shall not exceed 3 metres per second in discharge piping, and 1.8 metres per second in suction piping.

·        Systems incorporating manifolding shall comply with the requirements of AS 1345-1995, Identification of the Contents of Pipes, Conduits and Ducts.

·        Filtration equipment shall be protected from tampering by unauthorised persons.

·        Filtration equipment shall be mounted level on concrete or another surface, which is easily cleanable and non-absorbent.

·        Plant room floors shall slope at a minimum 1:50 gradient towards a floor drainage system.

·        Each filter vessel shall be installed so that it can be isolated from the recirculation system for repairs and backwashing.

·        All water treatment plant shall be installed with sufficient access, to enable them to be inspected and serviced in accordance with manufacturer’s specifications and safe working practices.

·        Filters cleaned by backwashing shall be provided with a readily observable sight glass, installed on the waste discharge line.  Sight glasses shall be of full line diameter and readily removable for cleaning.

·        Facilities using cartridge filters shall be provided with a wash-down area, with drainage connected to a waste disposal facility approved by the local government.

 
Balance Tank Capacities and Personnel Accessibility
Balance tanks form an integral part of the hydraulic performance of the water treatment system.

Balance tanks shall be sized, to allow for the following:

• Bather displacement based on the maximum instantaneous load rating for the facility.
• Volume of water available to backwash all primary filters at one time.
• A reserve for start-up after backwash, freeboard and wave displacement of not less than 20% above the sum of 1 and 2. 

Where entry is possible into a balance tank, it shall be designed in accordance with the requirements of the Occupational Safety and Health Regulations 1996 (Part 3 Division 8 “Work in Confined Spaces".)

Requirements for Water Features
The water supply for all water features shall consist of filtered, disinfected water obtained from the return side of the filtration system.  This requirement applies to water features such as waterfalls, fountains, mushrooms, or other design features through which water enters an aquatic facility.

High water volume features (water slides, rivers etc), must draw their water from a chlorinated and filtered water supply. If any water is drawn from the balance tank directly into a water feature, all make-up water must be chlorinated before entering the balance tank, to achieve a minimum level of 2 milligram per litre free chlorine.