Algal Alerts in the Lachlan
Catchment
15th March 2016
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: Lachlan Sampling 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
Sampling Site
Sampled
Date/Alert
Total BGA cells
mL / BVEq total BGA
mL / BVEq
potentially toxic BGA
20 May
2014
No alert
Lake Wyangala Dam Wall
Stn 1 (41210001)
13 Jan 2016
Nil
Lake Wyangala at Grabine
Stn 2 (41210002)
17 Feb 2016
Nil
Lake Wyangala Lachlan Arm
Stn 3 (41210003)
17 Feb 2016
Amber
Lake Wyangala Lachlan Arm
Stn 4 (41210004)
17 Feb 2016
Nil
Lake Wyangala Abercrombie
Arm Stn 5 (41210005)
17 Feb 2016
Green
Lake Wyangala State Park
Stn 7 (41210007)
17 Feb 2016
Nil
Lachlan River D/S Wyangala
Dam (412067)
10 Feb 2016
Amber
Carcoar Dam Stn 1
(4120021)
10 Apr 2013
Amber
Carcoar Dam Rec Area
(41210191)
10 Feb 2016
No Alert
Belubula River D/S Carcoar Dam
(41210106)
Lachlan River @ Cowra
Previous
Alert
Dominant species
* Potentially toxic
0 C/mL
mm3/L BVEq
mm3/L BVEq
Nil
2686 C/mL
0.03 mm3/L BVEq
0.03 mm3/L BVEq
Green
1992 C/mL
0.02 mm3/L BVEq
0.02 mm3/L BVEq
Green
77658 C/mL
0.2 mm3/L BVEq
0.07 mm3/L BVEq
Green
2328 C/mL
0.01 mm3/L BVEq
0.0 mm3/L BVEq
Nil
1780 C/mL
0.01 mm3/L BVEq
0.00 mm3/L BVEq
Green
0 C/mL
0.0 mm3/L BVEq
0.0 mm3/L BVEq
Nil
152,200 C/mL
3.2 mm3/L BVEq
3.2 mm3/L BVEq
Green
111502 C/mL
2.45 mm3/L BVEq
2.45 mm3/L BVEq
0 C/mL
0.0 mm3/L BVEq
Amber
* Microcystis flosaquae
Nil
C/mL
mm3/L BVEq
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
800 999 457 Page 1
Algal Alerts in the Lachlan
Catchment
15th March 2016
Sampling Site
Sampled
Date/Alert
12 Jan 2016
No alert
Total BGA cells
Previous Alert
mL / BVEq total BGA
mL / BVEq potentially
toxic BGA
Lachlan River @ Forbes
Cottons Weir (412004)
661 C/mL
0.01 mm3/L BVEq
mm3/L BVEq
Dominant species
* Potentially toxic
Nil
627,835 C/mL
12 Jan 2016
Amber
Lake Forbes
22 Feb 2016
No Alert
Goobank Creek@Goobang
Weir
22 Feb 2016
No Alert
Lachlan River @ Condobolin
Bridge (412006)
3 Mar 2015
No Alert
Lachlan River
@ Condobolin Weir (412034)
10 Feb 2016
Amber
Lake Cargelligo Intake D/S
Curlew Water (41210155)
10 Feb 2016
Amber
Lake Cargelligo TWS Site 2
(41210042)
17 June 2014
No Alert
Lake Cargelligo Site 3 Main
Swimming Area (41210043)
10 Feb 2016
Nil
Lachlan River at
Lake Cargelligo Weir
(412011)
1.81 mm3/L BVEq
0 mm3/L BVEq
Amber
0 C/mL
0.0 mm3/L BVEq
0 mm3/L BVEq
Nil
0 C/mL
0.0 mm3/L BVEq
0 mm3/L BVEq
Nil
0 C/mL
mm3/L BVEq
mm3/L BVEq
Nil
34 C/mL
0.0 mm3/L BVEq
0.0 mm3/L BVEq
Nil
27,750 C/mL
1.0 mm3/L BVEq
0.3 mm3/L BVEq
Nil
6,098 C/mL
0.01 mm3/L BVEq
0.01 mm3/L BVEq
Green
*Cylindrospermopsis
raciborskii
0 C/mL
0.0 mm3/L BVEq
0.0 mm3/L BVEq
Amber
54,235 C/mL
10 Feb 2016
Amber
Lake Cargelligo Boat Shed
(4121543)
10 Feb 2016
Amber
Lake Creek @ Lake
Cargelligo Outlet (412008)
14 May 2014
No Alert
Lachlan River
at Lake Brewster Weir (412048)
12 Jan 2016
No Alert
Lake Brewster Intake
(412102)
2.1 mm3/L BVEq
0.4 mm3/L BVEq
Amber
24,520 C/mL
1.1 mm3/L BVEq
0.9 mm3/L BVEq
Nil
0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq
Amber
*Anabaena
640 C/mL
0.01 mm3/L BVEq
0.01 mm3/L BVEq
Nil
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
800 999 457 Page 2
Algal Alerts in the Lachlan
Catchment
15th March 2016
Sampling Site
Sampled
Date/Alert
Total BGA cells
Previous Alert
mL / BVEq total BGA
mL / BVEq potentially
toxic BGA
19 Nov 2013
Amber
Lake Brewster
Main Storage at Regulator
(41210197)
1 Dec 2015
No alert
Lake Brewster Outlet Channel
D/S Regulator C (41210196)
12 Jan 2016
Nil
Lake Brewster Inflow
Wetland
U/S Spillway (41210195)
12 Jan 2016
No alert
Lake Brewster Storage Gauge
(412108)
23 June 2014
No Alert
Lake Brewster Outlet
@ Bensons Drop Weir
(412047)
18 Dec 2015
No alert
Lachlan River at Willandra
Weir (412038)
16 Feb 2016
Amber
Lachlan River at
Hillston Weir
(412039)
16 Feb 2016
Amber
Lachlan River at Booligal
Weir
412005
2 Mar 2016
Amber
Lachlan River at Corrong
(412045)
Dominant species
* Potentially toxic
978,.282 C/mL
1.09 mm3/L BVEq
0 mm3/L BVEq
Nil
Cyanocatena
0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq
Nil
170,293 C/mL
0.01 mm3/L BVEq
0.01 mm3/L BVEq
Green
0 C/mL
0.0 mm3/L BVEq
0.0 mm3/L BVEq
Nil
2346 C/mL
0 mm3/L BVEq
08 mm3/L BVEq
Green
Microcystis
aeruginosa
0 C/mL
0 mm3/L BVEq
0 mm3/L BVEq
Nil
10,916 C/mL
1.74 mm3/L BVEq
0.1 mm3/L BVEq
Nil
6298 C/mL
1.28 mm3/L BVEq
0.2 mm3/L BVEq
Amber
223,138 C/mL
4.88 mm3/L BVEq
1.0 mm3/L BVEq
Amber
9,930
3 Feb 14
Amber
Cadiangullong Dam
3
mm /L BVEq
Amber
* Dolchiospermum,
Aphanizomenon
2.76 mm3/L BVEq
39,496 C/mL
22 Feb 2016
Amber
Gum Bend Lake
3.0 mm3/L BVEq
Amber
0.2 mm3/L BVEq
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.
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
800 999 457 Page 3
Algal Alerts in the Lachlan
Catchment
15th March 2016
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 Sub committee of the State Algal Advisory Group
Key to alerts for recreational waters
Blue-Green Algal Level
Alert Definition
GREEN ALERT
GREEN
>500 – <5,000 cells/mL
Microcystis aeruginosa OR
biovolume equivalent of >0.04 to
<0.4 mm3/L for the combined
total of all cyanobacteria

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 ALERT
AMBER
≥5,000 – <50,000 cells/mL
Microcystis aeruginosa OR
biovolume equivalent of >0.4 to <
4.0 mm3/L for the combined total
of all cyanobacteria where a
known toxin producer is
dominant OR ≥0.4 to <10 mm3/L
for the combined total of all
cyanobacteria where known toxin
producers are not present.

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 ALERT
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

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
800 999 457 Page 4