Fire Fighting Water Tank Requirements

Climate change experts are predicting an increase in the number and intensity of bushfires across Australia in the next few years. As a result of the intense bush fires across Australia in the last few years, all States have developed a set of requirements and guidelines for the storage of water in different locations.

Bushfire Prone Land

The NSW Rural Fire Service (NSW RFS) has defined bush fire prone land (BFPL) as land identified by the local council which can support a bush fire or is subject to bush fire attack. They have developed bush fire prone land maps and resources such as:

• Building in Bush Fire Prone Areas
• Water Supply for Fire Fighting Purposes

In Queensland, the Queensland Fire Emergency Service (QFES) uses the terms Bush Fire Hazard Area (BFHA) interchangeably with Bush Fire Prone Areas (BFPA) and have produced different shapefiles for 13 different regions across Queensland. For example:

• Bushfire Prone Area – Wide Bay Burnett Spatial Data Format

Bushfire Attack Level (BAL) Rating System

A common feature of the requirements is the Bushfire Attack Levels (BALs) which were developed to help State and National Governments indicate to property owners and builders the different requirements for each of the different levels of bushfire risk. The six BALs based on radiant heat flux exposure threshold are as follows.

• BAL-LOW: No specific bushfire protection measures are required as the risk is minimal.
• BAL-12.5: Low risk, with potential ember attacks. Radiant heat exposure can be up to 12.5 kW/m².
• BAL-19: Moderate risk, with potential ember attacks and burning debris. Radiant heat up to 19 kW/m².
• BAL-29: High risk, with increased ember attack and radiant heat exposure up to 29 kW/m².
• BAL-40: Very high risk, with significant ember attack and potential flame contact. Radiant heat exposure up to 40 kW/m².
• BAL-FZ: Flame Zone, the highest risk, with direct flame contact and extreme radiant heat exposure above 40 kW/m².

BAL Ratings and Water Requirements

• BAL-LOW to BAL-19 (Low to Moderate Risk):
  Typically, no specific water tank requirements for bushfire protection apply, though having a dedicated water supply is often recommended for added safety.
• BAL-29 (Moderate to High Risk):
  Properties at this level of risk may be required to have a dedicated water supply of around 5,000 litres to 10,000 litres for bushfire protection, especially in rural areas.
• BAL-40 and BAL-FZ (High to Extreme Risk):
  For properties with higher risk levels (BAL-40 and BAL-FZ, where FZ stands for Flame Zone), a dedicated water supply of at least 10,000 to 20,000 litres is often required.
  The water supply must be accessible by the local fire authority, and a “Storz fitting” for NSW or a “Cam Lock fitting” for QLD [connected to a 50mm outlet, with ball valve] might be mandated.

BAL Ratings for Locations in Queensland

To determine the exact BAL rating for a specific location in Queensland, a site-specific BAL assessment is required. This involves examining vegetation, slope, and bushfire history near the property​.

Get a step by step tutorial for identifying the Bushfire Attack Level (BAL) for your QLD property

BAL Ratings for Locations in NSW

To find out the specific BAL rating for a location in NSW, you can use the NSW Rural Fire Service’s Bush Fire Prone Land Tool, which allows you to check if a property is in a bushfire-prone area based on local council maps. Local councils may also provide BAL assessments for properties within their jurisdictions.

Get a step by step tutorial for identifying the Bushfire Attack Level (BAL) for your NSW property

Australian Standard AS3959 Construction Requirements

Buildings in areas identified as having a BAL rating must meet specific construction standards. These include:

• Use of fire-resistant materials such as metal or treated timber.
• Ember protection: sealing gaps and installing mesh screens to prevent ember attacks.
• Non-combustible materials for roofs, external walls, and windows

Key Documents and Resources

New South Wales (NSW)

• Planning for Bush Fire Protection (PBP) 2019
• Australian Standard AS3959
• NSW Bushfire Prone Land Mapping Tool
• Biodiversity Conservation Act 2016
• BASIX (Building Sustainability Index)

Queensland (QLD)

• The Queensland Government’s State Planning Policy
• Queensland Development Code MP 2.4 (Building in Bushfire-Prone Areas)
• Australian Standard AS3959
• Queensland Bushfire Hazard Area Mapping
• Bushfire Resilient Communities Guide

Water Tank Installation for Bushfire Protection

Factors to consider when setting up a water tank in a bushfire prone area

• There needs to be a clear space around the tanks site so that there is nothing that could burn and so that the local fire service truck can get good access to the tank outlet.
• Your draw-off outlet needs to be fitted with the correct hose connections to connect to the local fire service appliances. Each State has a different fitting. For example, a Storz fitting is needed in NSW and a Camlock fitting in Qld.
• Exposed PVC pipes and fitting will melt in a fire so make sure your valves and pipe fittings are made from metal to ensure they can withstand high temperatures.
• Do not rely on an electric pump as power will most likely be cut off during a bush fire. It is best to have a diesel or petrol driven pump and your generator needs more than 1,5kVa capacity to drive the pump.
• The generator and pump should be able to pump a minimum of 400 litres per minute and must be built with shielding from high temperatures.
• You can install a dedicated water tank for firefighting purposes only or you could install a combination water tank where water can be stored for both firefighting and domestic use.

Rainwater Quality in Bushfire-prone Areas

If like many people in Australia you live in bushfire-prone areas and also happen to depend on the rainwater harvested from your roof(s) for essential living or to supplement you local municipal water supply.

Rainwater quality can become problematic as bushfires can produce large amounts of smoke, ash and other debris which can land on the roof and contaminate the rainwater being collected. Fire retardant material and fire-fighting foaming agents can also end up on the roofs and interfere with the quality of the rainwater being harvested.