Stormwater, Flooding and Drainage

The cause of most concerns regarding stormwater entering properties is excessive rainfall. Due to the topography of the peninsula, excessive rainfall causes overland flow of water or, if the soil has already become saturated, water flow below ground level.  

You are legally obliged to capture, collect and dispose of stormwater from all hard surfaces through your stormwater legal point of discharge.

For more information you can download the Mornington Peninsula Shire Flood and Stormwater Strategy from our strategies and plans listing.

Stormwater legal point of discharge

Learn more about the approved legal point of discharge from your property and the requirements for legal stormwater discharge.

Stormwater issues from neighbouring properties

Your neighbour is not responsible for controlling stormwater runoff from natural surfaces, such as grassed or treed areas – but they are responsible for controlling waterflow resulting from changes made to the natural ground.

Problems with overland stormwater flow between neighbouring properties are generally a civil matter to be resolved between the respective owners. We recommend talking to your neighbour about any stormwater issues that you are experiencing or writing them a short note to make them aware of the problem. If you are unable to resolve the issue with your neighbour, you can contact the Dispute Settlement Centre of Victoria (DSCV) for advice or mediation. You can also engage a solicitor to pursue legal action, liability resulting from the flow of water is an offence under the Water Act Section 16.

Stormwater issues during construction

Individual builders are responsible for management of stormwater on a building site during construction, for example, when a building under construction temporarily features a roof without gutters or downpipes. If you have concerns about the management of stormwater on a building site during construction, you can report these concerns to the builder or the private building surveyor, whose details will be displayed at the front of the building site.

Stormwater easements

Stormwater easements form part of the drainage infrastructure of your property.  If you wish to build over an easement you will need permission.  Learn more about building over easements.

Stormwater Quality

Modification of the natural characteristics of a catchment, through processes such as land use change and development, has a significant impact on the nature of stormwater runoff. With changes to natural catchments, such as urbanisation and the establishment of agricultural areas, the range and load of pollutants delivered to receiving environments has increased. Their accumulation within the receiving environment can result in severe and often irreversible impacts, which ultimately affect the quality of life enjoyed by the community.

The Mornington Peninsula Shire Stormwater Management Plan has been developed to improve the environmental management of stormwater within the Shire. Improvements in stormwater quality are necessary to meet the community’s expectations and values regarding the health and quality of the local receiving environments.

Stormwater management is concerned with the development and implementation of strategies to minimise the impacts of stormwater pollution and protect the receiving environment. Strategies to manage stormwater can include a range of site specific structural and non-structural measures as well as plans, policies and procedures aimed at managing activities which could potentially result in stormwater pollution. 

Download: Mornington Peninsula Drainage Outlets Report 2016.pdf(PDF, 2MB)

Soak Pits

Our peninsula has more than 1500 soak pits processing our stormwater.  These are most commonly found in the south-western end where the land is without gullies and creeks, limiting drainage.  Soak pits are man-made drainage systems located out of sight and at the end of our stormwater drainage network.  The pits collect incoming water from the surface in a large porous walled chamber until the water slowly seeps into the earth.  Soak pits have been strategically placed throughout our peninsula to process excess stormwater after heavy rain, keeping our roads and pathways safer for our community.

Download: Soak pit fact sheet(PDF, 518KB)

Water Sensitive Urban Design

Water Sensitive Urban Design (WSUD) incorporates a variety of initiatives to assist in the collection and management of stormwater runoff in an efficient, cost effective and environmentally friendly way. The goal of WSUD is to reduce the quantity, while improving the quality of stormwater runoff to your waterways, thus improving environmental outcomes for surrounding rivers and streams. WSUD technologies include:

  • Rainwater tanks
  • Streets with swales instead of traditional kerb and channelling
  • Vegetation buffers or filters within swales
  • Swales with infiltration capability
  • Sediment and retention basins
  • Rain-gardens
  • Wetlands and
  • Retention ponds and detention ponds

For information on how to build a raingarden, please see Melbourne Water's website Raingardens.

The key principles of Water Sensitive Urban Design as stated in the Urban Stormwater - Best Practice Environmental Management Guidelines (Victorian Stormwater Committee, 1999) include:

  • Protecting natural systems by protecting and enhancing natural water systems within urban developments. Promoting and protecting natural waterways as assets allows them to function more effectively and supports the ecosystems that rely on them.
  • The Integration of stormwater treatment into the landscape by using stormwater in the landscape by incorporating multiple use corridors that maximise the visual and recreational amenity of developments. The natural stormwater drainage system can be utilised for its aesthetic qualities within parklands and walking paths, making use of natural topography such as creek lines and ponding areas.
  • Protecting water quality by improving the quality of water draining from urban developments into receiving environment. Through filtration and retention, water draining from urban developments can be treated to remove pollutants close to their source. This approach reduces the effect that polluted water can have upon the environment and protects the natural waterways.
  • Reducing runoff and peak flows by reducing peak flows from urban development by local detention measures and minimising impervious areas. Local detention and retention enables effective land use for flood mitigation by utilising numerous storage points in contrast to the current practice of utilisation of large retarding basins. This approach subsequently reduces the infrastructure required downstream to effectively drain urban developments during rainfall events.
  • Adding value while minimising development costs by minimising the drainage infrastructure cost of the development. The reduction of downstream drainage infrastructure due to reduced peak flows and runoff minimises the development costs for drainage, whilst enhancing natural features such as rivers and lakes that add value to the properties of the area. 

Download: Water Sensitive Urban Design in a Changing Climate(PDF, 369KB)

An example of a large scale WSUD asset delivered by council is the Rye Bioinfiltration Basin.