Stormwater and roofwater run-off and how to manage it
Redland City Council often receives complaints from residents about stormwater run-off, also known as natural overland water flow. This water flows from neighbouring properties and can collect mud, rubbish, metals and other pollutants along the way.
Neighbourhood disputes about natural overland water flow are a civil matter and Council has very limited authority over what it can and cannot do to intervene in such cases.
Council encourages property owners to work together to resolve stormwater problems and consulting a licensed drainer may help provide solutions.
Natural overland water flow
Flooding caused by natural overland water flow is a common event that occurs where land slopes, directing water from neighbouring properties or public land to the lowest point. An upstream resident cannot be held liable if natural overland water flows from their land onto their neighbour’s property. However, the upstream resident may be liable if their actions result in increased or more concentrated water flow.
NB: residents are responsible for ensuring any natural overland water flow on their property does not impact buildings by having adequate drainage systems to collect and redirect water.
Ideally, overland water flow should be directed towards the street or a drainage system (also known as a ‘lawful point of discharge’) where available.
Property owners are encouraged to talk to their neighbours about any stormwater problems and seek a mutually satisfactory solution. If this is not possible without a third party, the services of a mediator may be sought through the Queensland Government. If one or both parties feel the situation cannot be resolved through mediation, legal advice may be required.
Managing natural overland water flow
Overland water flow or surface water resulting from rainfall can cause properties to flood if it is not properly managed.
Redland City is prone to bursts of intense rainfall, leading to significant amounts of surface water.
Where a piped drainage system is unavailable or unable to cope, the resulting surface water will take its natural course downhill and across adjoining land.
This is a natural occurrence and can be effectively managed by following some simple guidelines:
- avoid altering the ground level around an overland flow path
- ensure your vehicle crossing has sufficient ‘rollover’ to prevent water from the road or channelling from flowing down your driveway
- ensure your driveway and other paved surfaces have an appropriate shape and levels to direct surface flow away from your garage and house
- avoid blocking the path of overland flow at both the upstream and downstream boundaries of your property
- in general, protect your home by ensuring ground levels around it direct surface flow away from the house.
For detailed information on managing stormwater and roofwater drainage, please refer to the Queensland Urban Drainage Manual.
Council's responsibilities
Council provides and maintains stormwater drainage infrastructure (such as roads, pipes and open drains) on public land to collect and redirect stormwater to creeks and rivers.
It also provides and maintains stormwater drainage infrastructure on some private properties via designated drainage easements.
Property owner's responsibilities
Property owners are responsible for effectively managing stormwater drainage and surface water on their own properties by maintaining stormwater pipes, gutters, downpipes, gully pits and other components, to minimise the chance of stormwater entering their homes. They are required to accept natural overland flow from adjoining properties or public land.
If there is a drainage easement on private property, the owner must maintain it and keep it clear of debris or other materials to allow the natural overland flow of stormwater.
When property owners lay hard-surface areas such as driveways, concrete and paved areas, and even landscaping, they must control stormwater and roofwater to prevent increased or concentrated flows onto adjacent or downstream properties by ensuring water run-off is drained to a lawful point of discharge, ie.:
- via a kerb adapter or into the kerb and channel in front of a property
- via an inter-allotment drainage system if the block slopes down away from the street
- to a Council-controlled drainage easement or reserve – requiring Council approval.
You cannot direct water flow to pool and become stagnant – this does not apply to dams, tanks, wetlands and ponds.
All roofwater infrastructure on Council property remains the property of the landowner, who is responsible for maintenance up to and including the connection point – i.e. where it meets the kerb adaptor and the surrounding concrete kerb.
This includes any underground roofwater pipes that connect from the property to Council’s kerb and channel.
The property owner is responsible for ensuring their roofwater system is correctly installed and legally connected to the stormwater system so it does not impact on Council’s infrastructure or community safety. Stormwater must NOT be directed into the sewer system.
When installing additional roofwater pipes, you must lodge an Approved Point of Discharge form – available at the bottom of this page – with Council before starting work.
Inter-allotment drainage
If your property sits below street level or slopes downwards away from the street, you will likely have inter-allotment drainage for your roofwater and/or overland water flow.
Inter-allotment drainage systems can carry water from as many as 10 properties or as few as two properties, depending on the age of the development.
Council does not maintain inter-allotment drainage systems. Affected property owners are responsible for working together to maintain these systems.
Drainage easements
A drainage easement is an area on privately owned land where a Council stormwater pipe or open drain passes through private property. These easements allow Council to access the stormwater infrastructure and carry out work when required.
Stormwater infrastructure can include open drain channels, below-ground pipe systems and grated inlets. It is designed to manage stormwater and roofwater, with large upstream catchment stormwater flows.
Generally, no structures or improvements (such as dwellings, extensions and sheds) are permitted within drainage easement boundaries. However, where this does occur, property owners are responsible for maintaining easements on private property.
Council is not responsible for vegetation maintenance, like clearing of weeds, trees or overgrown vegetation in or around watercourses or drainage easements on private property, but Council may carry out maintenance work around stormwater drainage infrastructure where there is a drainage easement on private property, to ensure the infrastructure operates effectively.
Property owners who need advice about their responsibility for drainage easements on their land should seek independent legal advice.