The Common Law position requires that the upstream landowner may not alter the property that would result in a change in the location, concentration, volume, velocity, frequency, duration or intensity of overland stormwater flows, such that an actionable nuisance could result. Further, the downstream landowner is bound to accept ‘natural’ overland stormwater but is not bound to accept flow which is altered as above or frequency by reason of development on the upstream land.
If the property has a stormwater installation, defined under the Local Government Act 2009 such as roof gutters, downpipes, subsoil drains and stormwater drainage for the premises, Council may direct the property owner to connect to Council’s stormwater drainage system, if available and practical to do so.
Drainage easements are registered on some land titles to provide legal protection for underground drainage systems and overland flow paths for stormwater run-off.
There are two ways of connecting roof water to a legal point of discharge:
Overland flow between private properties usually occurs when the natural terrain is sloping;
Where there is a dispute relating to overland flow, and where the work carried out by the ‘offending’ owner is not work which is regulated under the Council’s Planning Scheme or the Standard Building Regulation, and does not otherwise constitute a contravention of any previous planning or building approval, the issue is a private one to be resolved by the owners under the Civil Law of Nuisance, and not a matter where the Council has any regulatory jurisdiction.