2011-2013: Wivenhoe Dam Recycled Water. Pesticides: 2,4-D, AMPA, Glyphosate, Dalapon, N-butyl benzenesulfonamide, Fenvalerate, Fluvalinate

My location
Get Directions
WCRW Scheme–Annual Report 2011-14

SEQ Water

Annual Report 2011-2012
Western Corridor Recycled Water Scheme
Recycled Water Management Plan

Lake Wivenhoe Point of Supply

Herbicides, pesticides and phenols
Two hundred and thirty herbicides, pesticides, phenols and their degradation products were tested for in the PRWat the Lake Wivenhoe Point of Supply.
A total of six pesticides, herbicides and their degradation products were det ected during the year (refer to Table 3-26):
• 2,4-D dichlorophenoxy AAC , a herbicide, was detected in two of 51 samples at concentrations of 0.02 and 0.04 μg/L. These concentrations are several orders of magnitude below the standard in Schedule 3b of the Public Health Regulation 2005 of 30 μg/L
•Aminomethylphosphonic acid, a degradation product of the herbicide glyphosate,was detected in one of the 51 samples at a concentration of 1.5 μg/L. No standard is set for this compound in Schedule 3b of the Public Health Regulation 2005 or the Australian Drinking Water Guidelines 2011, however, it is included in the residue definition for glyphosate (refer to ‘total glyphosate’ below), forwhich there is a standard.

•Dalapon, a pesticide, was detected in several samples of PRW from the Lake Wivenhoe Point of Supply at concentrations up to 0.17 μg/L. This concentration is several orders of magnitude lower than the standard of 500μg/L in Schedule 3b of thePublic Health Regulation 2005. Although dalapon is a pesticide, it is suspected that it is forming as a disinfection by-product of chlorination (Hawker et al. 2011) in the PRW.

•Glyphosate, a non-selective herbicide, was detected in one of 51samples at a concentration of 1.7μg/L. This concentration is several orders of magnitude below the Standard in Schedule 3b of the Public Health Regulation 2005 of 1000 μg/L.
•Reporting of total glyphosate, which is the sum of glyphosate and its metabolite
aminomethylphosphonic acid expressed as glyphosate equivalent, commenced in January 2012. There has been one test result above the limit of reporting (which was on the same sample that aminomethylphosphonic acid was detected) with a result of 1.5 μg/L. The residue definition for glyphosate (which the standard is based off), relates to total glyphosate and as such, this result isseveral orders of magnitude below the standard in Schedule
3b of the Public Health Regulation 2005 of 1000 μg/L.
•N-butyl benzenesulfonamide, a fungicide and plasticiser, was detected in several samples of PRW from the Lake Wivenhoe Point of Supply. This compound was first detected at a concentration of 61.23 μg/L. Investigations (refer to Section 4 Incident and Investigations
for full details) identified that the likely source of this compound was contamination (leaching) from the long plastic pipe used to transfer the water from the PRW main to the tap used for sampling. Subsequent results for this compound have been below the limit of reporting (< 0.02 μg/L). Due to this variability in the detected concentration of this compound the log normal 95th and 99th percentiles are significantly higher (at 114.50μg/L and 1111.90 μg/L respectively) than the maximum concentration detected (61.23 μg/L).
These may be compared to an interim guideline, derived following the methodology described in the Australian Guidelines for Water Recycling (Phase 2) Augmentation of Drinking Water Supplies (2008), of 262 μg/L (Leusch 2012)– refer Section 4 Incidents and Events.
2,4-D 0.04ug/L (max)
AMPA 1.5ug/L (max)
Dalapon 0.17ug/L (max), 0.09ug/L (av)
Glyphosate 1.7ug/L (max)
N-Butyl Benzenesulfonamide 61.23ug/L (max), 11.23ug/L (av), 114.5ug/L (95th LN Percentile), 1111.9 (99th LN Percentile)…
DEET, an insect repellent, in two of 52 samples at a concentration of up to 0.02μg/L compared to a standard of 2500μg/L
DEET 0.02ug/L
http://www.seqwater.com.au/sites/default/files/PDF%20Documents/Publications/20130212-WCRW-RWMP-Annual-Report-WEB.pdf
Annual Report 2012-2013
Western Corridor Recycled Water Scheme
Recycled Water Management Plan

Lake Wivenhoe Point of Supply

Herbicides and Pesticides
One hundred and ninety one herbicides, pesticides, and their degradation products were
tested for in the PRW at the Lake Wivenhoe and AWTP Points of Supply. A total of four
pesticides, herbicides and their degradation products were detected during the year (refer to Table 3- 26) as follows:

2,4-D dichlorophenoxy AAC, a herbicide, was detected in six of 65 samples at maximum concentration of 0.02 μg/L. Th is concentration is only just above the analytical limit of reporting (0.01μg/L) and is several orders of magnitude below the Standard in Schedule 3b of the Public Health Regulation 2005 of 30 μg/L

2,2- Dichloropropionic acid (dalapon) , a pesticide, was detected in 35 of 87 samples of
PRW from the Lake Wivenhoe and AWTP Points of Supply at concentrations up to 0.25
μg/L. This concentration is several orders of magnitude lower than the Standard of 500
μg/L in Schedule 3b of the Public Health Regulation 2005. Although dalapon is a
pesticide, it is suspected that it is forming as a disinfection by-product of chlorination (Hawker et al. 2011) in thePRW.
Fenvalerate, an insecticide, was detected in one of 54 samples at the Lake Wivenhoe
and AWTP Points of Supply, at a concentration of 1μg/L. This concentration is well
below the Standard (50μg/L) in Schedule 3b of the Public Health Regulation 2005.
Fluvalinate, also an insecticide, was detected in one of 51 samples at a concentration of
1μg/L. This compound has no Standard in Schedule 3b of the Public Health Regulation
2005 or guideline value in the Australian Drinking Water Guidelines 2011.
http://www.seqwater.com.au/sites/default/files/PDF%20Documents/Publications/2012-13%20WCRWS%20Annual%20Report.pdf