Information

Nutrient losses under simulated rainfall from pasture plots in the Great Lakes District, New South Wales

Level 1 General description

Purpose:

To determine the processes by which nutrients and solids enter waterways from pastures in the Great Lakes district in New South Wales.

Methods (brief)

Rainfall simulations, using a 100-year return storm event, were conducted to determine nutrient and suspended solid concentrations in the runoff of 8 pasture sites in 3 of the catchments in the district.

Key findings (brief)

  • On 5 of the 8 sites, considerable concentrations of N or P were mobilised during the simulated rainfall event, but average nutrient concentrations and total loads across all sites were relatively low and similar to other studies of nutrient runoff from pastures.
  • Rainfall runoff responses at the sites were similar in the 3 catchments.
  • Pastures generated peak nutrient concentrations soon after the commencement of runoff and declined by the end of the rainfall event.
  • Due to high to very high infiltration, runoff is not found to be a major pathway for nutrients in the area.

Location

Wallamba catchment

Related studies

The same experiment was carried out on sites in the Myall and Wang Wauk catchments.

 

Level 2, Level 3, Level 4 and Level 5