Hobart City Council – flood forecasting
Client: Hobart City Council
Location: Hobart, Tasmania
Date: 2010
Developing an updated flood forecasting system to provide timely flood warnings that allow better flood management and improve public safety.
Background
Hobart City Council (HCC) is responsible for flood management in the system of creeks and rivulets that flow through Hobart, the capital city of Tasmania, Australia. HCC required an updated flood forecasting system to be able to provide timely flood warnings and improve flood management.
Solution
The HCC engaged Entura to develop an automated flood detection system for the three major rivulets that flow through Hobart. The system is linked into the Council’s flood management plan for the city.
The system comprises a network of stream flow and rainfall gauges that transfer data directly to a time-series database via radio and satellite communications. A hydrological rainfall-runoff-routing model produces forecast flows. Hydraulic models were developed to establish relationships between flows and levels at critical points in flood-prone areas throughout the city, providing real-time flood level forecasts at ungauged locations. Alarms are triggered during floods, which notify personnel by email and SMS. A web-based application presents the output.
An ongoing program is in place to maintain the monitoring sites and communications and to provide support to the models and operating system.
Entura undertook the hydrologic and hydraulic modelling, and developed the user interface and web-based output displays. This involved high levels of expertise in developing and calibrating hydrologic and hydraulic models, programming, and web-based interface development.
Outcome
The web-based interface allows operators to visualise the potential extent of forecast floods via a map showing inundated areas. The system provides HCC with timely and accurate forecasts of flooding throughout Hobart, allowing appropriate management actions to be put in place for improved flood control and increased public safety.