What are local flood warning and flood forecasting systems: As the title implies it is a system that consists of rainfall and river gauging stations, weather and flood forecasters, local flood intelligence and modelling, and mechanisms to deliver a warning to the community. It is the intention of these systems “to help flood management agencies and the members of flood-prone communities to understand the nature of developing floods so that they can take action to mitigate their effects”(Attorney-General’s Department, 2009).

Improves community access and recreational use:

Not applicable. Why? Local flood warning systems and flood forecasting are designed to predict when a flood will occur, how high and fast will the water flow, and what you should do. As a result they cannot improve community access and recreational use.

Does not disadvantage individual members of the community:

Local flood warning systems and flood forecasting generally do not disadvantage individual members of the community. Why? Local flood warnings derived from flood forecasting are generally provided to the entire community at risk through multiple modes such as telephone calls, media broadcasts, text messaging, and door knocking.

Provides safety to the community during flooding:

Local flood warning systems and flood forecasting provide safety to the community. Why? These systems give community members in advance the opportunity to know what is likely to occur, prepare for flooding, and move to a safe area or evacuate. They also provide a heads-up to emergency service personal to prepare for and respond to flood impacts.

Raises community awareness and understanding of the local flood risk:

Local flood warning systems and flood forecasting improve community awareness and understanding of the local flood risk. Why? These systems can predict flood heights and flows prior to events, informing the community of the likely flood event impacts.

Does not threaten local plants and animals and their habitat:

Not applicable. Why? Local flood warning systems and flood forecasting are designed to predict when a flood will occur, how high and fast will the water flow, and what you should do. As a result they may allow for the rescue of local animals prior to a flood event however, this rarely occurs as the focus is on disseminating information to protect lives and property.

Does not cause water quality issues:

Local flood warning systems and flood forecasting can improve water quality Why? These systems can allow community members to prepare for flooding which can include placing contents and chemicals above predicted flood heights hence, reducing the potential impacts of these items washing into nearby rivers or streams.

Initial Costs (i.e design/construction) require minimal council expenditure:

Local flood warning systems and flood forecasting have major initial costs to council Why? As previously stated these systems usually consist of a network of rainfall and river gauging stations, local flood modelling, and mechanisms to deliver the warning to the community. To provide indicative costs:  individual river and rain gauge stations typically cost around  $15,000 per station to set up, if you have a network of 3 this totals $45,000; local flood modelling to determine timings and impacts typically cost around $100,000 for a catchment, but is usually completed as part of a flood risk management study and plan; and mechanisms to alert the public through dissemination systems such sirens and text messaging services have establishment costs of around $30,000. This equates to total initial costs of between $70,000 to $180,000.

Requires minimal ongoing council expenditure after implementation:

Local flood warning systems and flood forecasting have moderate ongoing costs to council Why? As previously stated these systems usually consist of a network of rainfall and river gauging stations, local flood modelling, and mechanisms to deliver the warning to the community. Maintenance needs to be performed on the rainfall and river gauging stations, in conjunction with the alert mechanisms to ensure their use during critical times. In addition flood modelling should be reviewed and updated following changes in the catchment (i.e. a major flood event, significant development). These maintenance costs typically range from $5,000 to $20,000 a year. 

Reduces flood damages to the community:

Local flood warning systems and flood forecasting reduce flood related damages to the community. Why? These systems give community members in advance the opportunity to know what is likely to occur and prepare for flooding. This can allow the community to pack, raise or relocate valuable objects and possessions above prior to the flood event reducing the devastating damages associated with flooding. Note: The warning time in flash flood environments may be very limited only allowing community members to evacuate or move to refuge areas. 

Does not cause negative flood impacts to other areas (both upstream and downstream):

Not applicable. Why? As stated previously, local flood warning systems and flood forecasting are designed to predict when a flood will occur, how high and fast will the water flow, and what you should do. As a result they do not cause negative flood impacts to other areas.

Attorney-General’s Department (2009). Manual 21- Flood Warning: Emergency Management Series. Commonwealth of Australia. Canberra, Australia.