Farm dams are essential infrastructure for many farming operations, including for livestock and irrigation. Healthy farm dams can provide higher quality drinking water for livestock, improve your farm’s productivity and provide habitat for a wide variety of native wildlife.
Dam water that is high in nutrients and animal faeces can lead to algal blooms, high bacteria loads and disease. Providing poor quality drinking water to livestock can have a negative impact on stock health, productivity and performance.
Unpalatable water, caused by high algae or bacteria loads will reduce the amount of water consumed by livestock. Animals with limited hydration have a lower capacity to absorb nutrients and minerals, which limits their performance.
In many agricultural landscapes, natural wetlands are rare and, if present, highly degraded. Decades of agricultural activity have led to many wetlands being intentionally drained or inadvertently drained when gullies and waterways erode. The few remaining wetlands are rarely spared from the detrimental impact of livestock.
While natural wetlands are now in short supply, thousands of farm dams dot the landscape and, with appropriate management, can help restore biodiversity by providing much needed wetland habitats for native wildlife.
With appropriate management, farm dams can deliver a number of benefits for stock productivity and become focal points for biodiversity.
Productivity and profitability benefits
There are a number of things you can do to improve the water quality and habitat of farm dams to enhance the productivity, profitability and biodiversity of your farm.
1. Exclude livestock, or control livestock access
The single most important step for enhancing farm dams is to exclude livestock from the area, or control livestock access. Implementing this step alone will dramatically improve the quality of drinking water available to your livestock.
Limiting livestock access to the area will reduce the direct effects of livestock on water quality, such as effects of excrement in the water and disturbed sediments, which results in mobilisation of nutrients.
Restricted access to the dam area helps to improve the dam by reducing livestock disturbance of vegetation, soil and sediments on the surrounding banks and in the dam itself.
Excluding stock or limiting stock access to the dam will also improve biodiversity and increase the environmental services that arise from this, such as the predation of pasture pests by frogs, birds, and invertebrates.
2. Provide drinking water via water troughs
Total exclusion of livestock from the dam area can be achieved if drinking water is available to livestock in water troughs. Some landowners are reluctant to rely on water troughs because of concern about potential malfunctioning. This concern can be overcome by providing hardened access points that are open at all times or are opened periodically at times when personnel are unavailable to conduct regular checks of troughs.
3. Allowing fringing vegetation to grow
Grasses and vegetation act as filters for the water and help to stabilise the dam bank. Retaining and restoring vegetation around the dam can improve its water quality. Fringing vegetation also provides wetland habitat for wildlife including native frogs, water birds and small native fish.
4. Create a grassed buffer zone in the inflow area
Having a well grassed buffer zone in the inflow area of your dam will help to improve water quality by catching paddock run-off such as sediment, animal dung and other pollutants. The larger the grassed inflow area, the more effective it will be.
5. Add logs, rocks, trees and shrubs to the dam area
Enhance the habitat and encourage native wildlife to colonise the dam by adding rocks, logs, trees and shrubs to the area. Trees and shrubs can also help to reduce evaporation by reducing wind and shading the water. Avoid planting trees and shrubs in the main inflow areas, spillway or on the dam wall as this will reduce the functionality of the dam. Many wetland plant species will naturally colonise the dam, but planting locally native wetland plants may help to speed up this process.
6. Create shallow areas in the dam
A healthy dam will attract a range of birds. Create shallow areas and perching sites in the dam to add to the diversity of the habitat and make it more attractive to wetland birds.
|Tips for installing hardened access points|
For more information, download the PDF guide to enhancing farm dams here.