Stormwater

 Stormwater

 

Stormwater generally means rainwater that runs off surfaces such as lawns, roads, roofs, car parks, driveways, patios and natural ground surfaces.

 

Under the Urban Drainage Act 2013, runoff water is defined as water which has been concentrated by means of a drain, surface channel, subsoil drain or formed surface. This means runoff generated from natural surfaces, such as grassed lawns and gardens is not regulated by Tasmanian law. 

 

Our role in managing stormwater

Council is responsible for maintaining all the public stormwater systems in the municipal area, including public stormwater mains, manholes and pits, and for managing major waterways to ensure their hydraulic function, and regulating private drainage.

 

If a property has a stormwater installation, such as roof gutters, downpipes, subsoil drains and stormwater drainage for the premises, but is not connected to Council’s stormwater system, then we may request that the property owner connects to our stormwater drainage system, if available and practical to do so.

 

The Urban Drainage Act 2013 also makes provisions for the control of stormwater, and we may issue property owners with a written notice if they breach the Act.

 

Your role in managing stormwater

It is important for all residents to play a part in keeping our region’s waterways healthy and functioning:

  • You must ensure any stormwater within your property or premises is collected and drained appropriately to comply with all relevant legislation, regulations, standards and Council policies.
  • You must maintain any approved private stormwater system on your property, including downpipes, gutters, private stormwater pipes, and gully pits, in a good operational condition.
  • You are not permitted to construct a barrier (e.g. dam, levy etc.) that interferes with the natural path of stormwater.
  • You are not permitted to divert or change the natural flow of stormwater.
  • You are required to control stormwater associated with any construction work which takes place on your property.
  • You must keep the easement free of debris if there is a drainage easement on your property, and free of obstructions to allow runoff passing through your property in a safety manner and to minimise the damage.

 

Discharging stormwater

Stormwater collected from an individual property can be discharged via the following points of discharge, subject to Council approval. Generally there is only one discharge point allowed for each lot:

 

  • to a kerb and gutter discharge point via gravity, particularly for those properties which fall directly towards the street
  • where the lot falls away from the street and there is a stormwater pipe or similar provided with an approved connection point to a public network, then the property must discharge to that drainage network
  • if gravity flow to either kerb and gutter or connection to the drainage network is not achievable, consideration may be given to other approaches, such as disposal onsite (soakage trench) or pressured flow via a pump station. However, these approaches require the specific approval from Council’s Building and Plumbing Services.

 

Please note: it is illegal to direct or discharge stormwater onto a neighbouring property.

 

Surface runoff

The Council’s underground stormwater system is designed for a certain amount of rain. When there is exceptionally heavy rainfall there is likely to be surface runoff. 

 

Surface runoff means the water, which, in extreme rainfall events, is unable to enter the underground drainage system, and naturally flows to the nearest watercourse via overland flow paths such as roadways, public reserves, pathways and sometimes through private property.

 

Surface runoff from neighbouring properties

Overland flow between private properties usually occurs when the ground surface naturally directs surface runoff to a neighbouring property. In addition, a property which has been excavated and modified such as creating tiers can also change the way a property sheds water. This can create a nuisance by sending stormwater runoff to other properties.

 

An upstream property owner is not responsible when surface water flows naturally onto an adjoining property, due to the existing shape of the land. However, if they change the layout of the land and don’t channel the water they may be liable, through civil action between private owners.

 

Ideally, runoff should be directed towards the street, or to a formal drainage system, if provided. It is recommended that property owners seek professional advice before starting any works which may change the drainage of the property.