Regular dam inspections needed after drought

Farm-dam

Regular inspection and monitoring of dams should be done regularly but this is far more critical over the next six to twelve months as dams start to fill after an extended dry period.

Regular inspection, monitoring and maintenance of your gully dams will significantly reduce the risk of failure from leaks and banks collapsing.

Stock damage, soil erosion, siltation and excessive vegetation growth all contribute to the gradual deterioration of farm dams.

The rapid rise in dam water levels following an extended period of drought and dry seasonal conditions also adds to the pressure on dam banks, spillways and pipelines.

Gully dams fail on a regular basis across Victoria due to poor soils, poor construction, dry soils and a lack of maintenance. Estimates suggest more than 20 per cent of gully dams in Victoria fail within a few years of being built.

Regular inspection and monitoring of dams should be done regularly but this is far more critical over the next six to twelve months as dams start to fill after an extended dry period.

Landholders are encouraged to carefully inspect and monitor their gully dams to pinpoint issues and act before the dam completely failed. He said landholders need to focus mainly on the dam bank, looking for signs of bank subsidence, cracking or tunnelling.

Regular inspection should include:

  • Monitoring water levels for signs of leakage
  • Checking the bank water line for unusual turbulence or whirlpools indicating a possible leakage area
  • Checking the dam bank for signs of cracking, tunnelling or settlement
  • Checking the dam bank and immediately downstream for signs of seepage, softness or lush vegetation
  • Checking the bank to ensure it is stable, firm, free of soil erosion, has at least one metre of bank above water level, a well-rounded crest and has a good cover of topsoil and grass
  • Ensuring dam banks and adjacent areas are free of woody vegetation, including trees and shrubs
  • Checking the spillway is stable, has good capacity and is free of debris and excessive vegetation
  • Checking the inlet area to ensure it is well grassed, stable and free of soil erosion, and
  • Checking for rabbit or stock damage.

Dam maintenance work involving the removal or destruction of native vegetation may require a planning permit, and landholders are strongly advised to check with their council planning officer before carrying out such work.

-Agriculture Victoria