The Environmental Management Program (EMPA2) commenced in 2002. The project aims to identify and minimise the risk of pesticides contaminating channel water.
Risk Assessment
One of the objectives of the EMPA2 is to assess the risks associated with pesticides used in Goulburn Murray Irrigation Areas. Accordingly, Goulburn-Murray Water (G-MW) engaged the Commonwealth Scientific Industrial & Research Organisation (CSIRO) to make a first tier assessment of the risks associated with pesticides used in G-MW irrigation areas to water quality and through changed water quality to humans, stock, food industries, pastures, aquaculture, aquatic flora and fauna and aquatic ecosystems.
In the risk assessment various transport pathways to channels (drift, accidental spill, unlawful acts, and drainage discharge), and potential exposure of different receptors (human, stock, domestic use, food processing, aquaculture, pastures, and crops) were considered. In addition, land use patterns (fruit, vegetables, crops, and pastures) in G-MW irrigation areas, environmental fate and pesticides toxicity data (LD50 for rats, LC50 for fish, LC50 for daphnia and EC50 for algae) were also included in the risk assessment
Some 83% of pesticides that were found to be high to very high risks to different receptors were found to be those that are used in fruit and vegetables production areas. The top 10 pesticides rated to be high to very high were organophosphate (azinphos methyl, methyl parathion, chlorpyrifos, omethoate), synthetic pyrethroid (esfenvalerate, bifenthrin), carbamate (methomyl), fungicide (thiram, mancozeb, and copper hydroxides).
The study recommended monitoring of pesticides residue levels in fruit, vegetables, pastures and aquaculture production areas within G-MW's six irrigation areas channels, a new survey to obtain pesticides usage data in new and expanding farming zones, and obtaining of ecotoxicological information of harmful pesticides
For further information you can email Golam Kibria.
To download a copy of the First Tier Assessment Report click on the first link at the bottom of this page
Monitoring
Year 1
In the 2004-2005 irrigation season (year 1 of a 2 year study) monitoring of pesticides and related heavy metals was conducted at 14 potential risk sites located across G-MW's six irrigation areas.
The risk sites included intensive orchards (pome & stone) and vineyards, vegetable (intensive tomatoes), reference sites, channel outfall, stock & domestic and town supply, and aquaculture.
The study includes deployment and retrieval of passive samplers, spot water sampling and analysis and interpretation of results of targeted pesticides and related heavy metals.
Monitoring found three agriculture chemicals on a regular basis across the six irrigation areas: endosulfan (an organochlorine insecticide, at 8 of the 14 sites), atrazine (herbicide, at 9 of 14 sites) and copper (fungicide, at most sites). These three agriculture chemicals were associated with intensive orchards (stone, pome fruit) and vineyards, vegetable (tomatoes) and pastures (legume plants). Other pesticides that were irregularly detected at some sites were chlorpyrifos and parathion methyl.
Levels of chemicals detected were generally within guideline values for a range of purposes. Elevated endosulfan levels detected at some sites may make channel water unfit for aquaculture. The second year monitoring results would confirm whether this is an issue or not.
Based on the first year of monitoring, it is concluded that the channel water is of good water quality and would be fit for most uses. The project will continue in the 2005/06 irrigation season.
For further information you can email Golam Kibria.
To download a copy of the Pesticide Monitoring Interim Report click on the second link below.
Monitoring - Year 2 and Final Report
During 2004-05 and 2005-06 irrigation seasons, a pesticide monitoring study was conducted at the 15 potential risk sites located within the six Goulburn-Murray Water irrigation areas in northern Victoria, Australia using a new, economical, innovative passive sampling technique.
The monitoring found three agriculture chemicals on a regular basis across the six irrigation areas. These were:- endosulfan (an organochlorine insecticide), atrazine (herbicide) and copper (fungicide). The two other chemicals that were found on an irregular basis were chlorpyrifos, and parathion methyl (organophosphates).
By comparison with national and international water quality guidelines (ANZECC 1992, ANZECC 2000) and others (Hamilton et al. 2003) -and ecotoxicological data (mammalian, fish, algae and daphnia, Tomlin (2000)), the water quality was found to be within the national standards for most purposes (irrigation, stock & domestic supplies, town supplies, recreation, aquatic ecosystems protection) for all the six irrigation areas investigated. However, water endosulfan and chlorpyrifos concentrations at some sites estimated from passive sampler's concentrations would have exceeded the recommended ANZECC guidelines for the purpose of aquaculture or fish farming.
The current report combines the two years monitoring results of pesticides and related heavy metals in the six irrigation areas. Based on the two years research study, it can be concluded that channel water in the six irrigation areas is of good quality and is safe for most beneficial usages including irrigation, stock & domestic supply, town supply and recreation and aquatic ecosystems protection. However, the study results suggest that there is potential risk of using channel water for the purpose of aquaculture or fish farming in particular where intensive orchards and vegetables (tomato) are being grown.
For further information you can email Golam Kibria.
To download a copy of the Pesticide Monitoring Final Report click on the third link below.
Pesticides in Irrigation Water
Goulburn Murray Rural Water Authority (G-MW) in collaboration with CSIRO, RMIT University, the Centre for Ecotoxicology, and the Primary Industries Research Victoria, organised a ‘Pesticides in Irrigation Water Workshop' in Tatura, Victoria, Australia (November, 2006). A number of key Australian scientists presented research papers on pesticides in G-MW channels, drains and natural carries. These includes passive sampling techniques for monitoring of hydrophobic and hydrophilic pesticides, two years pesticide and heavy metals monitoring results; pulse exposure of herbicides on native fish larvae and tier 1 and tier 2 risk assessment for herbicides used by G-MW
For further information you can email Golam Kibria.
To download a copy of the Pesticide in Irrigation Water Workshop Abstract click on the fourth link below.