Dam decision-making options
Enhancing existing dams
Maybe you have enough storage, but want to increase water quality and retention, enhance biodiversity, or flexibility in cation of water points. In this case, choosing one or more dams to enhance is an excellent investment.
Alternatively, a need for additional storage may be met through renovation (de-silting and/or enlarging) of an existing dam. This would ideally be coupled with fencing and revegetation.
Considerations for the management of existing dams include:
- Is there a particular large dam that would be suitable as the farm’s primary water source? If so, what enhancements can be made to improve the dam’s water holding capacity and water quality?
- Are there particular dams that might be suitable for modifications to support biodiversity, for example located near a vegetation patch or that could be incorporated into a fenced revegetation area?
- Smaller dams that have silted up or dry out easily may be candidates for decommissioning, if the farm’s water requirements are met with larger dams that retain water for longer. Alternatively, one or more of these dams might be suitable for modifications to support biodiversity.
- Can a change in dam management help address a problem such as erosion, or support landscape rehydration? For example, fencing and enhancing a dam to reduce bank erosion.
- Is the dam leaking? If so, can it be repaired and improved, or is it a dam that can’t make a strong contribution to the farm’s water supply and therefore could be a could candidate for decommissioning?
For more information on dam enhancement and improved management see Section 2.
Do I need a new dam?
Having undertaken a process of farm water planning as outlined above, the conclusion may be that a new or significantly larger dam is required to meet a farm’s water requirements.
Landholders will need to check regulations on dam construction and harvestable rights in their state or region as a permit may be required. Contact your regional water authority.
Note that the construction of new dams has implications at a landscape and hydrological level, as water captured by dams is water that is not sustaining downstream rivers and wetlands.
For more information on dam construction see Section 3.
Decommissioning ineffective dams
Some dams are ineffective and are not required for a farm’s water system, and also not providing significant habitat for biodiversity. Given that such dams may still be holding water that would otherwise be utilised downstream, and that they will also contribute to a farm’s water-holding capacity under state regulations, there can be value in decommissioning these dams.