Ground water

Within the Mornington Peninsula Shire groundwater is found in the Port Phillip and Western Port groundwater basins. This groundwater is used for irrigation, stock watering and garden watering.

The use and protection of groundwater throughout Victoria is controlled by the Department of Environment, Land, Water and Planning (DELWP) and regional water authorities.

Before using groundwater on the Peninsula a license must be granted by Southern Rural Water to construct a bore and unless the water is being used for domestic and stock purposes, most groundwater use will also require a licence..

The water bore must be constructed by a Licensed Driller. Further information on water bore licensing can be obtained from the Southern Rural Water link at the bottom of this page.

The quality and quantity of groundwater can vary widely. Groundwater is untreated and should not be considered safe for human consumption without proper treatment.

For further information on the how groundwater occurs across Victoria and its uses please view the following DELWP  information sheets:

Victorian Groundwater(PDF, 57KB)
Western Port Groundwater(PDF, 37KB)
Port Phillip Groundwater(PDF, 39KB)

Groundwater Contamination

With widespread use of groundwater across the Peninsula it is important that contamination of groundwater basins is prevented. Chemicals, oil, household waste, corroded bores and sewage all pose risks to the local groundwater and should be prevented from entering groundwater.

There are many ways you can minimise the risks of groundwater contamination on your property in several areas.

Reduce the risk of chemical contamination of groundwater by:
• Applying chemicals according to manufacturer’s instructions
• Storing and using chemicals well away from a groundwater bore
• Checking sprayer equipment to ensure proper calibration so that the recommended application rates are not exceeded
• Putting devices on all taps and hoses to fill pesticide and herbicide sprayers to prevent back siphoning
• Disposing of containers and unwanted chemicals through the Government collection program or via a private chemical salvage firm
• Reducing the effects of spills by storing and using chemicals in bounded areas and with liquid traps designed for the task

You can also assist to minimise the risks of groundwater contamination on your property by:
• Ensuring that groundwater bores are constructed to an appropriate standard
• Engaging a Licensed Driller, who can assist in obtaining a Bore Construction License from Southern Rural Water
• Ensuring that your septic tank system is located at least 20 metres from any water bore, including any bores on neighbouring properties

The Nepean Peninsula Groundwater Study concluded that on-going contamination of ground water by septic tank effluent exists in certain areas of the Peninsula.

In response to these findings, bore water users in the Nepean Peninsula between Boneo and Portsea have been advised by Southern Rural Water not to use bore water for drinking or human consumption.

However, reticulated sewerage is now available to all residential properties in the Nepean Peninsula via South East Water’s Early Connection Option (ECO) sewer program. These properties are considered to be “serviced properties” under S.64  of the Water Industry Act.

Property owners can apply to connect  by contacting the Early Connections Team on:
Phone: 1800 720 613
Visit: 2449 Pt Nepean Road, Rye (between the car wash and the Rye Hotel) 
Post: Peninsula ECO Project, Locked Bag 1, Moorabbin VIC 3189

Under EPA Publication 891.3 – Code of Practice, On Site Wastewater Management, Councils cannot issue a septic tank permit if a property has sewer is available. New and altered dwellings in this area must either connect to reticulated sewerage or install an advanced grey water re-use system with toilet wastewater discharged to sewerage.

New and altered dwellings on rural properties in this area that do not have sewer available require a secondary wastewater treatment system and on-site irrigation to protect the groundwater aquifer and public health. For further queries please contact the Shire’s Environmental Health Team on phone 5950 1373 or email  

For more information visit our section on Septics - Wastewater Management 

Department of Environment, Land, Water and Planning:

Southern Rural Water: