Salinity and yield of groundwater in Port Phillip & Western Port

Where salinity is low and yield is high groundwater use is well established. The most reliable areas of good quality, high yielding groundwater in the region are found around Koo Wee Rup and on the Nepean Peninsula. Other reliable areas can be found across the region, generally within Groundwater Management Unit boundaries.

How much fresh water is stored in aquifers across the region?

Fresh water = salinity less than 1,000 mg/L

It is estimated that a total of 3,660 GL of fresh water is stored across the region: 660 GL in the upper aquifer, 1,000 GL in the middle aquifers and 2,000 GL in the lower aquifers. Estimates of fresh water stored in the basement are not available.

What is the quality and yield like in local areas?

Salinity (quality) and yield vary greatly across the region. They depend on where you are and which aquifer group you are using. To get an accurate indication of the quality and yield you can expect on your property you need to drill a bore and have the water tested.

To view this information on a map visit the Port Phillip & Western Port region map or you can download or print a summary of the likely salinity and yield of groundwater near your property on the Department of Environment, Land, Water and Planning website.

Salinity and yield by local area

Aquifer group	GMU or area	Salinity	Yield
Upper	Merrimu GMU	Good	Moderate
	Deutgam GMU	Good	Good
	Lancefield GMU	Very good	Moderate
	Nepean GMU	Very good	Very good
	West of Melbourne (non GMU area)	Very poor	Good
	North of Melbourne (non GMU area)	Moderate	Poor
	East of Melbourne (non GMU area)	Moderate	Poor
	South-East of Melbourne (non GMU area)	Moderate	Good
Middle	Frankston GMU	Good	Moderate
	Koo Wee Rup GMU	Good	Very good
	Moorabbin GMU	Good	Moderate
	Western Plains (west of Melbourne)	Poor	Poor
Lower	Wandin Yallock GMU	Very good	Moderate
	Corinella GMU	Moderate	Good
	Cut Paw Paw (GMU)	Poor	Very good
	Parwan (below Merrimu GMU)	Good	Good
	The Highlands (non GMU)	Good	Poor
	Mornington Peninsula (below Nepean GMU)	Moderate	Good
	South-East of Melbourne (non GMU)	Moderate	Good
	West of Melbourne (non GMU)	Poor	Good

This table shows a summary of the likely salinity and yield in different areas and aquifer groups.

Learn the basics

For background information on salinity visit our What is groundwater salinity page.

For background information on yield visit our What is groundwater yield page.

What is groundwater salinity? Find out more

What is groundwater yield Find out more

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