Lakes & Waterways

Our Water Quality – what can you do?

• Avoid swimming near stormwater, creek or river outlets 24-48 hours after heavy rain
• Swimming in Lake Colac and estuaries is not recommended and at swimmer's own risk
• Prevent pollution: do not litter and pick up after your dog to reduce rubbish and waste washing into waterways

Our Water Quality – your health 

The responsibility for managing the water quality of Lake Colac falls to a number of agencies and organisations such as DEECA, Department of Jobs, Precincts and Regions, CCMA, EPA, Barwon Water and Colac Otway Shire Council.

Council is conducting monthly tests from October – March at the Lake Colac beach area and the boat ramp at Meredith Park, Colac.

As yet, no specific point source/polluter has been identified; a number of possible sources for poor water quality in Lake Colac, Wye River and Kennett River.

The Australia and New Zealand Environment and Conservation Council (ANZECC) advises that until 100 samples have been gathered, analysis is difficult, and therefore water users should consider the results of water testing currently undertaken as a “snapshot”, and swimming in Lake Colac and estuaries is at the swimmer’s risk.

Council has a public health responsibility when it comes to providing advice to members of the public on the suitability of Lake Colac, Kennett River and Wye River for swimming/recreational activity.

While Lake Colac had experienced low water levels and a lack of activity over a number of years, higher rainfall in recent years and Council’s work to improve the foreshore area has encouraged more visitors to the foreshore and enabled recreational water use to occur.

The return of yachts and other lake users prompted Council to test the water quality from December 2018 and develop a water testing plan to provide information to the community.

According to the Australian and New Zealand Environment and Conservation Council (ANZECC) guidelines for primary contact the median enterococci organisms per 100mL over the season should not exceed 35 org/100mL.

Similarly, for secondary contact the median enterococci organisms per 100mL over the season should not exceed 230 org/100mL.

Primary contact is defined as recreation where you are in direct contact with the water, can be fully immersed and could swallow water; this includes water skiing, diving and swimming. 

Secondary contact includes boating.

Direct sunlight certainly plays an important part in improving the water quality because enterococci is susceptible to sunlight.   

However, any lake or river which can be contaminated with animal faeces from wildlife and other animals such as dogs will have levels of enterococci.

Water quality tests at Lake Colac, Wye River and Kennett River can assist the public make informed decisions about recreational water use.

	Lake Colac Boat Ramp	Lake Colac Meredith Park	Wye River	Kennett River
Test Date	Enterococci organisms/100ml	Enterococci organisms/100ml	Enterococci organisms/100ml	Enterococci organisms/100ml
December 2018	88	103	330	24
8 January 2019	>2400	>2400	Not taken	Not taken
18 January 2019	>2400	>2400	350	250
4 February 2019	1000	550	Not taken	Not taken
18 February 2019	400	260	Not taken	Not taken
April 2019	20	10	74	120
22 October 2019	26	6	27	16
21 November 2019			86	140
28 November 2019	20	20
17 December 2019	800	<10	41	52
16 January 2020	17
26 February 2020	2900	2600	410	880
12 March 2020	110	52	63	41
10 October 2020	470	330	120	10
14 December 2020	4000	1800	180	20
5 January 2021	2800	1200	74	52
17 February 2021	63	270	310	41
4 August 2021				42
1 September 2021				8
14  December 2021	41	10	41	130
5 January 2022	180	110	680	1200
8 February 2022	160	41	120	20
5 April 2022	41	<10	240	150
12 October 2022	31	10	<10	31
9 November 2022	<10	20	10	10
14 December 2022*	E.coli: 52	E.coli: 63	E.coli: 220	E.coli: 20
11 January 2023	30	20	590	2300
8 February 2023	86	360	820	710
8 March 2023	10	210	3900	1700
12 April 2023	180	10	3900	190

*Due to a lab error, only E.coli results were obtained in December 2022.