Flood Risk Management Committee (FMC)
The Flood Risk Management Committee is an advisory committee established under the NSW Flood Prone Land Policy to guide flood risk management within local councils. Its primary role is to advise on developing and implementing floodplain risk management plans and policies. The FRMC reviews flood studies, risk management plans, and guidelines, recommending their adoption to the Council. It follows the NSW Flood Risk Management Manual, which outlines standard flood risk assessment and mitigation procedures. While its focus is not on individual land use decisions, the FRMC influences land use policies, ensuring they are aligned with flood risk reduction objectives. Importantly, the FMC focuses on land use and flood risk management for flood-prone areas. It does not address emergency management but informs land use planning to reduce flood risk under section 733 of the Local Government Act 1993.
Flood Risk Management Plans (FRMP)
Council develops and implements Flood Risk Management Studies and FRMP to identify high flood-risk areas and propose measures to mitigate those risks through policy. These plans are developed in consultation with the community, flood specialists, the FRMC and relevant authorities. Whilst FRMP consider evacuation routes, they are not intended to be used as evacuation or emergency management plans. These plans focus on land use and flood risk management for flood-prone areas.
Land use and development planning
Council regulates land use and development in flood-prone areas through the Lismore Local Environmental Plan (LEP) and Development Control Plans (DCP), ensuring that flood risk is correctly managed in accordance with flood risk management guidelines and statutory requirements.
Flood risk mapping and data management
Council continually monitors flood risk and ensures that flood risk mapping is current. Flood maps are vital for the public, developers, and emergency management professionals to make informed decisions. Council has free Property Flood Certificates available for the urban and southern areas of the Lismore Local Government Area.
Local Emergency Management Committee (LEMC)
Council provides executive support to the Local Emergency Management Committee (LEMC), responsible for developing and coordinating emergency plans.
Flood warning and communication systems
Council works with the NSW State Emergency Service (SES) and Bureau of Meteorology (BoM) to ensure flood warning systems are in place. It provides real-time updates to the community through various communication channels, including Council’s Facebook and Instagram social media accounts and the Council website. It also disseminates warnings issued by the corresponding lead agency.
Flood mitigation and telemetry monitoring systems
Council maintains and operates flood mitigation measures such as the Lismore Levee and some rainfall and/or water level gauges (hydrometric/telemetry monitoring systems).
Community education and engagement
Council engages the community in flood preparedness through education campaigns, providing resources on flood risks, collaborating with Emergency Management agencies and groups and holding public consultations to involve residents in flood risk management strategies.
Serve as a conduit for key information
Council shares critical flood-related information from emergency service providers, including the NSW SES, NSW Police, and other agencies, to ensure the community is informed about current flood conditions, evacuation advice, and safety updates. This includes disseminating warnings issued by emergency services.
Support the lead emergency service provider
Council assists the NSW SES and other emergency services by providing necessary resources, including equipment, personnel, and facilities, to support flood management and recovery actions in accordance with the Local Emergency Management Plan.
Monitor flood impacts and manage infrastructure
The council continuously monitors its levee system, pump stations, and telemetry systems (such as rainfall and river gauges) to assess flood risk and take immediate action when necessary. This includes ensuring levee systems function as intended and operating pump stations to manage water levels effectively.
Monitor and manage roads and public spaces
Council monitors Council-owned roads, public reserves, and open spaces for any flood impacts. Roads may be closed, and detours put in place where required. Crews are deployed to remove fallen trees or other obstacles to maintain access. Council assists emergency services with traffic management support in evacuations.
Continuity of essential services
The Council ensures essential services, including water and sewer systems and waste collection, continue during a flood. Contingency plans are activated to minimise service disruptions and the public is kept informed about any service changes or temporary closures.
Support the Local Emergency Management Committee (LEMC), Local Emergency Operations Controller (LEOCON) and Combat Agency
If the Emergency Operations Centre (EOC) is activated at the Local Emergency Operations Controller's (LEOCON) discretion, Council provides executive support to the emergency response. This includes acting as a liaison between the EOC and Council and providing additional staff, such as communications officers, technicians and subject matter experts, coordinating and organising the deployment of equipment (such as power generators, mobile pumps, cranes, etc.) to support the operational needs of the EOC and emergency services and providing emergency services.
There are 32 gates along the levee that Council staff close at varying stages depending on the river level. The first three gates at Upper and Lower Hollingworth Creek (South of Kyogle Road and at Riverview park) and Gasworks Creek are closed when the river reaches 4m. All other gates are closed in a specific sequence when the river reaches or is predicted to reach 5, 6 and 7m.
The final gates under 11 Molesworth Street are closed at 9m. The temporary pop up deflector walls in Keen Street and Richmond Lane are constructed when it is predicted that the levee will over-top. Timing of the closure of some gates can vary depending on whether cars are still parked in the Kirklands Riviera, Rowing Club, and the Upper and Lower Hensley carparks behind the levee wall.
When severe weather is predicted, motorists should not park in carparks on the river side of the levee as vehicles may be damaged by rising flood waters.
There are five deflector walls within the Brown Creek Floodway. These are designed to provide some protection to the buildings within the floodway from fast flowing water when the levee overtops through the Browns Creek Floodway. They are at the Clive Campbell Carpark toilet block, the driveway to bottle shop behind Mary G’s, Keen Street at Singh’s Tyre and Mechanical and Lismore Antiques and Richmond Lane.
The CBD and South Lismore levees are designed to protect the city from a 10% Average Exceedance Probability event (formerly referred to as a 1-in-10-year flood).
Since it was built, it has only overtopped three times in March 2017, and February and March 2022. The lowest and first overtopping point is at the spillway opposite the old Police Station in Molesworth St. However, even though the design height of the levee is 10.95m at the spillway, the levee may actually overtop when the official Wilsons River Height gauge at the Rowing Club is around 10.2 – 10.6m (with 10.2m being possibly the worst case). This depends on the amount of rain falling in the Leycester and Wilson catchments and the downhill slope of the surface of the flood water. The slope varies from flood to flood. The variable level at which the river will overtop is due to the overtopping point being located some 500m or so up river from the official gauge site.
The second overtopping point is at Gasworks Creek south of the CBD which has a design level of 11.3m. The third overtopping point is in Spinks Park where the levee wall has a design level of 11.6m. The inundation is staged and the overtopping points positioned in order to minimise the impacts of fast flowing water on properties and infrastructure as it flows in. Our second levee is designed to protect South Lismore also from a 10% AEP. It has two sections which are between the Bruxner Highway and Wilson Street (4.7km) and Riverview Park to Wardell Street (400m). The South Lismore Levee is designed to overtop at Caniaba Street, north of Three Chain Road at 11.55m, flowing into Hollingworth creek, but can overtop anywhere north from here, depending on flows from Leycester Creek.
There is a range of large and small pumps that are activated during a flood to extract rainwater from within the levee walls and pump it into the Wilsons River. All pumps except the one at the old RSL, which Rous County Council is currently repairing, have been restored to pre-February 2022 conditions. The largest two pumps are at the Browns Creek Pump Station.
They are the original pumps from the 1960s when Browns Creek was first filled in and the carpark built over the tunnel that the creek now runs though. When the CBD levee was constructed, the pumps were refurbished and upgraded to increase their capacity.
Once the river height reaches 5.2m, the Browns Creek gate is closed and the first pump automatically kicks in. If the height reaches 5.4m, the second pump automatically starts. They both operate until the height of the river drops below 5.4m, when pump 2 stops, with pump 1 continuing until the height drops to 4.8m. If the height rises again to 5.2m, the cycle restarts and will do so while ever the gates are closed. The levels are dictated by the intake levels of the pumps and the depth of water required to operate the pumps without damaging them.
Each pump has a capacity of 3000 litres per second. In the event of the CBD gates being closed and we experience more than 5mm of rain per hour, the capacity of these pumps will be exceeded and some flooding in the basin should be expected. The Gasworks Creek gate is closed at 4m and also has two pumps that operate on the same principle at Browns Creek pumps but start at different heights.
Pump 1 starts at 6.4m and pump 2 at 7m. Both stop at 5.5m. Each pump has a capacity of 2000L/s Lower Hollingworth and Upper Hollingworth Gates close at 4m. The one pump at the Lower Hollingworth Gate starts at 4m. This pump is designed to keep water out of South Lismore. These three pumps are now connected to our Telemetry 24/7 monitoring system, which means they can be controlled remotely.
There are six additional smaller pumps in the CBD near the old RSL (currently non-operational), Bowling Club/Spinks Park, the Transit Centre, Glasgow Lane, Woodlark Street (near bridge) and an optional one at Three Chain Road (near Coates Hire) if required. Contingency plans are in place should we experience flooding before the RSL pump is operational.