SRDC Research Project final report Irrigation runoff event monitoring

Abstract

A major concern of the Burdekin irrigated sugarcane growing industry is the impact of nutrient runoff on the waterways and the surrounding environment. In line with the current Commonwealth and State Government’s Reef Water Quality Plan and the NRM regional plans, growers expressed the desire to evaluate the current situation to be able to address these concerns. This project was designed to enable growers to monitor runoff from their paddocks when irrigating and to assess the resulting. A trailer was designed and fitted with a solar power ISCO Avalanche refrigerated pumping sampler. It was designed to be a mobile unit that could easily be moved to any site within the MAFIA grower group area. The intention has been to make this unit available to any other grower group within the Burdekin area. During this project a number of training days were held and information disseminated to other grower groups through presentations at regional field days and workshops. Event sampling was carried out by growers in the MAFIA group which they then paid to have tested for nitrate concentrations. This information allowed growers to assess nitrate concentrations in runoff from irrigation of plant cane and discussions about the results were carried out with the members. Although a good wet season this year has limited the number of irrigation events available to monitoring. Great interest was expressed in further use of the sampling trailer to compare different fertiliser application methods and bedding practices to evaluate best management practices. The fact that the MAFIA group paid to have a consultant test the water samples shows their commitment to the success of the project and ongoing use of the water sampling trailer. A baseline survey was carried out at the start of the project and a follow up survey was done at the end of the project. Even with the weather constraints this year there has been an indication from these surveys that over 50% of growers in the group have made recent changes to their irrigation practices as a result of this project. It has provided the MAFIA members with degree of ownership of their runoff issues. This has highlight to an already aware group the extent of runoff and possible future investigations in improvement of irrigation practices. There has been a perceivable increase in the confidence of growers in the group about the validity of the sample data collated as it directly relevant to them.