Dams are essential infrastructure for many farming operations, including for livestock and irrigation. Enhancing a farm dam can lead to improvements in water quality and provide habitat for a wide variety of native wildlife.
Farm dams have become essential infrastructure for water storage on farms across Australia over the past century, with a focus on digging more and bigger dams in recent decades. There are now around 1,765,000 farm dams in Australia, including more than 650,000 in the Murray-Darling basin alone (Malerba et al. 2021 and Srikanthan et al. 2015).
These dams store a huge amount of water, yet traditionally there has been minimal investment in improving the quality and retention of water in these dams.
In recent years, some farmers have taken steps to enhance existing dams and have noticed the benefits this brings to water quality and to biodiversity on their farms.
Sustainable Farms research is now beginning to demonstrate these benefits through science. By comparing enhanced and unenhanced farm dams, our research shows that enhanced dams have better quality water and support more wildlife than traditional, unenhanced dams.
Farm dams provide essential water resources for stock, as well as much needed wetland habitats for native wildlife, including the: Banjo Frog (left: photo by Mason Crane); Welcome Swallow (top centre: photo by David Smith); Australasian Grebe (bottom centre: photo by Damien Esquerre); and Water Rat (top right: photo by Dan Florance). Bottom right: a well-vegetated farm dam (photo by Suzannah Macbeth).
“The fenced dam seems to have the most life around it and all sorts of reeds in it, and it’s really clear. It didn’t go dry in the drought – the dam kept giving, it was good water. We underestimate what an asset good water is to animals’ weight gain and general wellbeing.” Jenny Bell, sheep farmer near Breadalbane, NSW
Traditional farm dams are usually set within a paddock, in a low point in the landscape where they collect and store water for use for livestock, irrigation and sometimes household use. Stock often congregate around dams, pugging the edges and sometimes polluting the water. As a result of grazing impact, the wall and shores of such dams are often bare of vegetation.
An enhanced dam is usually, but not always, fenced to manage the impact of stock on the dam. It has healthy, native vegetation in and around the dam, providing many benefits for water quality and wildlife. As a result of stock exclusion and vegetation, the water is cleaner. An enhanced dam may also have other features such as a hardened access point for stock, variable depths, islands or snags.
Enhanced dams can provide better quality drinking water, retain water for longer, support native plants and animals, and provide ecosystem services to the surrounding landscape.
These two photos are of dams on the same property - at left an unfenced dam; at right, a fenced, vegetated dam. These photos were taken on the same day during the drought in 2019. Photos by David Smith.
Sustainable Farms researchers have surveyed 57 farm dams in NSW and Victoria. The study will continue for a further two years, but initial results show:
Sustainable Farms ecologists collected water samples from 125 dams and natural waterbodies across 35 farms in NSW and north-east Victoria. The samples were on a range of measures that indicate water quality.
Piping water from a fenced enhanced dam to a trough is an effective way to provide clean water to stock.
Some native animals, particularly water birds like the Australian wood ducks, will use almost any dam in the landscape regardless of its condition. However, there are many other species that are rarely observed on traditional dams but can be found on healthy, enhanced dams.
For example, platypus are generally found in streams and rarely in dams, but have been observed by Sustainable Farms researchers using enhanced dams. Birds like the spotless crake, little grassbird, golden-headed cisticola, diamond firetail and white-faced heron all use enhanced, well-vegetated farm dams – but not traditional dams.
In many agricultural landscapes, natural, healthy wetlands are extremely rare. But there are many farm dams, and when these dams are carefully managed, they can play a similar role to natural wetlands – helping restore biodiversity by providing much needed wetland habitats for native wildlife.
The eggs and tadpoles of Perons Treefrog (sometimes known as the Maniacal Cackle Frog due to its distinctive call) can be found in farm dams. Photo by Damien Esquerre.
A specific bird breeding study undertaken by Sustainable Farms is beginning to show that where farm dams and native vegetation are co-located in the landscape, bird breeding activity and success are greatly increased.
This doesn’t only apply to waterbirds – a range of other birds like stubble quails, golden-headed cisticolas and Australian reed-warblers (pictured) breed more often and more successfully when dams and vegetation are co-located.
An enhanced farm dam is well-vegetated both within and around the dam. Usually, this requires fencing to exclude livestock, although in some cases dams can retain good surrounding vegetation with sensitive grazing management.
Click each step below to find out more about how to enhance a farm dam.
Establish fences to exclude or limit stock access to the dam. This reduces fouling from faeces and pugging, limits sedimentation of the dam, and enables persistence of vegetation around the dam.
Water from fenced dams can be piped to troughs.
However, if a backup supply of water is required when troughs can’t be checked, partially-fencing a dam can allow limited stock access.
In this case, a hardened access point can minimize pugging and sedimentation, as well as reducing the amount of time stock spend in or on the edge of the water.
Once a dam is fenced, vegetation will begin to regrow naturally. This can be supplemented with strategic planting or seeding. In particular, riparian and wetland vegetation might need a helping hand to re-establish, particularly if the dam is a long way from other water bodies.
When constructing a new dam or mucking out an old one, this is a great chance to vary the depth of the dam.
A deep ‘borrow pit’ – the main excavated area of the dam – is important for water storage and retention. Shallow shelves in other parts of the dam, particularly the inflow zone, are important for enabling aquatic vegetation to establish. This vegetation will play an important role in filtering inflow, keeping the water cleaner and providing habitat for wildlife.
Islands, either solid or floating, provide safe nesting sites for waterbirds and turtles away from predators like foxes. The addition of semi-submerged timber (snags) in a dam provide great habitat for native fish, basking sites for animals such as turtles, and acoustic platform for calling frogs.
Watch our video on building artificial islands here.
Features of an enhanced farm dam.
What to plant in and around your dam
Native vegetation in and around a farm dam has many benefits for water quality, farm productivity and biodiversity. This brochure provides guidance on the types of plants suitable for revegetating dams, and includes lists of recommended plants.
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Benefit-cost analysis lends support for improved farm dam management
New Sustainable Farms research looking at the potential net benefits from enhancing farm dams has yielded promising results.
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Improving farm dams: a farmer’s perspective
Marcus Richardson runs a beef property near Albury in NSW. During the drought, he spotted an opportunity to protect some of the farm’s most vital assets – the dams. In this video, he explains why and how he decided to protect and enhance his farm dams for multiple benefits.
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