Level 2: Detail of Experimental Conditions and Methods


The study measured the loss of nutrients, pesticides and sediment in surface drainage from irrigated sugarcane farms. The study quantified those inputs / losses by measuring inflows and out flows.

The key objectives of the study included:

  • Measure irrigation water entering cane fields and leaving by surface drainage for several cane farms in the Burdekin River Irrigation Area (BRIA);
  • Quantify sediment, nutrient and pesticide input and outflow in irrigation and surface drainage water for these farms;
  • Identify nutrient and pesticide movement through the soil profile via the use of strategic core sampling;
  • Identify practices that reduce / minimise environmental impacts; and
  • Extend these measures to industry.

When and Where?

Nine farms were chosen at random for gauging. Hydrology and water quality monitoring commenced in 1995 and ceased in 1996, encompassing two wet seasons.

The farm had a runoff area of 105.2 ha. Soil distribution on the farm was similar to Farm 7D, but with higher proportion of non sodic duplex soils.


A rain gauge was installed at each drainage site to collect data specific to the location being monitored.

Drainage water samples were collected using ISCO 3700 programmable auto samplers. Sampling event were triggered by water levels sensors, set to initiate sampling 1 minute after farm overflows commenced. Spot samples were collected from irrigation inflows for nutrient, pesticide and turbidity analyses.

The handling of the samples included:

  • Each sample had a small amount of sodium thiosulfate solution added for sample preservation; and
  • One of the samples were used as a break down sample. the remaining samples were treated with a few drops of 0.1% phenyl mercuric acetate to prevent biological breakdown of nitrate and ammonium-nitrogen.

Analyses for ammonium-n, nitrate-n, phosphorus, sulfur, potassium, calcium, magnesium and sodium were carried out at BSES Indooroopilly laboratories and the result were reported in mg/L.

Pesticides were also analysed at BSES Indooroopilly laboratories and subsequently by Environmental Consulting at Oakley Victoria.

Farm inflows were determined by measuring the discharge rate of pumps or flow rate in fluming and elapsed time of delivery. Outflows from each farm was measured via a single installed structure as part of the dam design.

Project administration

Principle Investigator Gary Ham

Principle organisations BSES Limited

Co Operating Organisations Sugar Research and Development Corporation


Level 1, level 3, level 4 and level 5