Algal Alerts in the Lachlan Catchment

19th February 2015

This blue-green algal alert report is based on routine monitoring undertaken by the Cowra, Forbes and Lachlan Shire Councils; State Water Corporation and the NSW Office of Water.

These alert levels apply to non consumptive or recreational contact. Drinking water safety thresholds are much more stringent.

Table 1: LachlanSampling Sites - Counts of potentially toxic blue-green algae (cells/mL total species and biovolume equivalent BVEq of total blue green algae and potentially toxic blue green algae).Bold = new result from previous report

Sampled Date/Alert / Sampling Site / Total BGA cells
mL / BVEq total BGA
mL / BVEq potentially toxic BGA / Previous Alert / Dominant species
* Potentially toxic
20 May 2014
No alert / Lake Wyangala Dam Wall
Stn 1 (41210001) / 0 C/mL
mm3/L BVEq
mm3/L BVEq / Nil
21 Jan 2015
Amber / Lake Wyangalaat Grabine
Stn 2 (41210002) / 164,000 C/mL
0.83mm3/L BVEq
0.83mm3/L BVEq / Nil
21 Jan 2015
No alert / Lake Wyangala Lachlan Arm
Stn 3 (41210003) / 43,100 C/mL
0.03 mm3/L BVEq
0.03 mm3/L BVEq / Nil
21 Jan 2015
Green / Lake Wyangala Lachlan Arm
Stn 4 (41210004) / 514,000 C/mL
0.24 mm3/L BVEq
0.24 mm3/L BVEq / Green
21 Jan 2015
No alert / Lake Wyangala Abercrombie Arm Stn 5 (41210005) / 0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq / Nil
21 Jan 2015
Amber / Lake Wyangala State Park
Stn 7 (41210007) / 102,000 C/mL
0.52 mm3/L BVEq
0.52 mm3/L BVEq / Nil
21 Jan 2015
No alert / Lachlan River D/S Wyangala Dam (412067) / 524 C/mL
0.02 mm3/L BVEq
0.02 mm3/L BVEq / Nil
14 Jan 2015Amber / Carcoar Dam Stn 1
(4120021) / 22,400 C/mL
0.61 mm3/L BVEq
0.61 mm3/L BVEq / Nil
10 Apr 2013
Amber / Carcoar Dam Rec Area
(41210191) / 111502 C/mL
2.45 mm3/L BVEq
2.45 mm3/L BVEq / Amber / * Microcystis flos-aquae
14 Jan 2015 No Alert / Belubula River D/S Carcoar Dam
(41210106) / 98 C/mL
0.0 mm3/L BVEq / Nil
Lachlan River @ Cowra / C/mL
mm3/L BVEq
Sampled Date/Alert / Sampling Site / Total BGA cells
mL / BVEqtotal BGA
mL / BVEq potentially toxic BGA / Previous Alert / Dominant species
* Potentially toxic
8 Oct 2014
No alert / Lachlan River @ Forbes
Cottons Weir (412004) / 0 C/mL
0 mm3/L BVEq
mm3/L BVEq / Nil
9 Sept 2014
2014
No alert / Lake Forbes
/ 203 C/mL
0 mm3/L BVEq
0mm3/L BVEq / Nil
19 Jan 2015
Green / Goobank Creek@Goobang Weir / 19844 C/mL
0.04 mm3/L BVEq
0 mm3/L BVEq / Nil / Aphanothece
30 Sept 2014
No Alert / Lachlan River @ Condobolin Bridge (412006) / 0 C/mL
mm3/L BVEq
mm3/L BVEq / Nil
19 Jan 2014
No Alert / Lachlan River
@ Condobolin Weir (412034) / 827 C/mL
mm3/L BVEq
mm3/L BVEq / Nil
20 Jan 2015
Amber / Lake Cargelligo Intake D/S Curlew Water (41210155) / 19,300 C/mL
2.51 mm3/L BVEq
2.51 mm3/L BVEq / Nil
20 Jan 2015
Red / Lake Cargelligo TWS Site 2
(41210042) / 47,700 C/mL
4.41 mm3/L BVEq
4.41 mm3/L BVEq / Nil / Anabaena
17 June 2014
No Alert / Lake Cargelligo Site 3 Main Swimming Area (41210043) / 6,098 C/mL
0.01 mm3/L BVEq
0.01 mm3/L BVEq / Green / *Cylindrospermopsis raciborskii
20 Jan 2015
No Alert / Lachlan River at
Lake Cargelligo Weir (412011) / 0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq / Nil
20 Jan 2015
Red /
Lake Cargelligo Boat Shed (4121543) / 46,000 C/mL
4.28 mm3/L BVEq
4.28 mm3/L BVEq / Nil / Anabaena
20 Jan 2015
No Alert / Lake Creek @ Lake Cargelligo Outlet (412008) / 40 C/mL
0.0 mm3/L BVEq
0 mm3/L BVEq / Nil
14 May 2014
No Alert / Lachlan River
at Lake Brewster Weir (412048) / 0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq / Amber / *Anabaena
10 Feb 2014
Green / Lake Brewster Intake
(412102) / 2979 C/mL
0.16 mm3/L BVEq
0.03 mm3/L BVEq / Nil
Sampled Date/Alert / Sampling Site / Total BGA cells
mL / BVEq total BGA
mL / BVEq potentially toxic BGA / Previous Alert / Dominant species
* Potentially toxic
19 Nov 2013
Amber / Lake Brewster
Main Storage at Regulator
(41210197) / 978,.282 C/mL
1.09 mm3/L BVEq
0 mm3/L BVEq / Nil / Cyanocatena
11 Mar 2013
No alert / Lake Brewster Outlet Channel D/S Regulator C (41210196) / 0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq / Nil
19 Nov 2013
Green / Lake Brewster Inflow Wetland
U/S Spillway (41210195) / 170,293 C/mL
0.31 mm3/L BVEq
mm3/L BVEq / Nil / Cyanocatena
7Jan 2014
Green / Lake Brewster Storage Gauge
(412108) / 581 C/mL
0.07 mm3/L BVEq
0.01 mm3/L BVEq / Nil / Cyanocatena
23June 2014
No Alert / Lake Brewster Outlet
@ Bensons Drop Weir
(412047) / 2346 C/mL
0mm3/L BVEq
08 mm3/L BVEq / Green / Microcystis aeruginosa
23June 2014
No alert / Lachlan River at Willandra Weir (412038) / 0C/mL
mm3/L BVEq
mm3/L BVEq / Nil
9 Dec 2014
No alert / Lachlan River at
Hillston Weir
(412039) / 18,374 C/mL
0.03mm3/L BVEq
mm3/L BVEq / Nil
9 Dec 2014
Amber / Lachlan River at Booligal Weir
412005 / 16,571C/mL
2.01mm3/L BVEq
0 mm3/L BVEq / Nil
9 Dec 2014
Amber / Lachlan River at Corrong
(412045) / 10858 C/mL
2.56mm3/L BVEq
0.0 mm3/L BVEq / Amber
3 Feb 14
Amber / Cadiangullong Dam / 9,930
mm3/L BVEq
2.76 mm3/L BVEq / Amber / * Dolchiospermum, Aphanizomenon
19 Feb 2015 / Gum Bend Lake / 26132 C/mL
0.28mm3/L BVEq
0. mm3/L BVEq / Nil

The bio-volume equivalent (BVEq)calculated for all contributing cyanobacteria species is used to determine alert thresholds. The total observed cyanobacteria genera that contribute to the current alert level are also presented.

It is recommend that water treatment and stock management responses should not be altered according to the observed cyanobacteria genera but that the BVEq Alert framework be applied. All cyanobacteria should be considered as potentially harmful to human and animal health when present in blooms.

River users and landholders are advised to avoid waters in areas subject to RED (High) alert levels or with visible algae scums. They should also consider either alternative sources of water for stock. NSW Health advises that any domestic use of surface water without treatment is dangerous and should be avoided. Note, boiling water contaminated with blue green algae does not remove toxins

Alert Definitions are as specified in The National Health and Medical Research Council (NHMRC) Guidelines for Managing Risks in Recreational Water 2008

The use of these guidelines is endorsed by the Scientific Subcommittee of the State Algal Advisory Group

Key to alerts for recreational waters

Blue-Green Algal Level /

Alert Definition

GREEN
>500 – <5,000 cells/mL Microcystis aeruginosaOR biovolume equivalent of >0.04 to <0.4 mm3/L for the combined total of all cyanobacteria / GREEN ALERT

Low levels of detected –base crop of blue green algae may be on the increase

ACTION
Continue/increase routine sampling to measure cyanobacteria levels
AMBER
≥5,000 – <50,000 cells/mL Microcystis aeruginosaOR biovolume equivalent of >0.4 to < 4.0 mm3/L for the combined total of all cyanobacteria where a known toxin producer is dominantOR ≥0.4 to <10 mm3/L for the combined total of all cyanobacteria where known toxin producers are not present. / AMBER ALERT

Indicates blue-green algae are multiplying
Water may have a green tinge and musty taste and odour

ACTION

Water supply authorities to commence filtering with activated carbon
Investigations into the causes of the elevated levels and increased sampling to enable the risks to recreational users to be more accurately assessed

RED
>50,000 cells/mL Microcystis aeruginosa OR biovolume equivalent of ≥ 4 mm3/L for the combined total of all cyanobacteria where a known toxin producer is dominant
Or
The total biovolume of all cyanobacterial material exceeds 10 mm3/L where known toxin producers are not present
Or
Cyanobacterial blooms are consistently present / RED ALERT

High levels detected
Indicates “bloom” conditions
Toxicity should be presumed
Water will appear green or brownish and may have a strong musty taste and odour
Surface scums could occur
Extreme care should be exercised, and contact with the water should be avoided

ACTION

Issue Media Release

Water supply authorities to increase filtering with activated carbon as appropriate

Local authority and health authorities to warn the public that the water body is considered to be unsuitable for primary contact recreation.

For media enquiries contact Public Relations Officer on 02 6701 9662.
For further information contact the Water Quality Officer at the NSW Office of Water, on (02) 8838 7517.

For toll free information on blue-green algae outbreaks contact the Algal Information Hotline - 1 800 999 457Page 1