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Report on 4 Mile Lake Water Quality

The monitoring of recreational water quality at public bathing beaches is a mandated program under the authority of the Mandatory Health Programs and Services Guidelines as authorized by the Health Protection and Promotion Act.

All such public beaches are monitored for bacteriological quality on a weekly basis over the bathing season (5 samples each week/minimum 9x per season) by Environmental Health Officers of the Haliburton Kawartha Pine Ridge District Health Unit.

[See latest 4ML Secchi depth History and 4ML Phosphorus History]

Contamination sources are monitored over the bathing season to determine and assess potential pollution sources and their potential impact on the suitability of beach water for public bathing purposes. Contamination sources include but are not limited to the following: · Streams · Private sewage disposal systems · Sewage treatment plants · Combined or storm sewer outlets · Industrial outlets · Sanitary landfills · Open dumps · Bird populations · Animal enclosures · Feed lots · Soil erosion areas · Marinas · Bather loads · Beach aesthetics (algae, dead fish) · Meteorological (rainfall, water currents, temperature)

Laboratory results are processed at the Public Health Laboratory in Peterborough and enumerated for E. coli bacteria. E. coli are bacteria found in the gastro-intestinal tract of warm blooded animals including humans. They indicate recent faecal pollution which potentially is a contaminate of the beach environment. Faecal matter, particularly that which is human in nature has the potential of carrying disease causing micro-organisms. E. coli bacteria is an indicator of faecal contamination. With such increases in the levels of E.coli in bathing beach water(>100 E. coli/100mL) comes an increased risk to bathers of acquiring infections of the GI tract, eye, skin and ears.

Environmental Health officers will consider posting a public bathing beach when the geometric mean taken from 5 samples is >100 E. coli per 100mL.

Four Mile Lake Beach is one such public bathing beach which is monitored regularly over the bather season. Historically this beach has yielded satisfactory bacteriological results with ONE beach posting over these two years. Below are the results from these bathing beaches for the years 2004 and 2005. The public bathing beach was posted once in 2005, in part as a result of heavy rainfall 24 hrs prior to sampling. See Table 1.1 below.

Table 1.1 Laboratory Results of Bacteriological Water Quality taken from Four Lake Beach 2004 and 2005(Expressed as E. coli cfu's/100mL).

Sampling Date: Geometric Mean

June, 14, 2005: 257**

June 21, 2005: 10

June 29, 2005: 10

July 4, 2005: 10

July 12, 2005: 10

July 18, 2005: 26

July 25, 2005: 11

August 2, 2005: 22

August 8, 2005: 10

August 15, 2005: 11

August 23, 2005: 11

August 29, 2005: 10

June 21, 2004: 11

June 29, 2004: 10

July 6, 2004: 11

July 13, 2004: 10

July 19, 2004: 10

July 26, 2004: 10

August 3, 2004: 10

August 25, 2004: 10

August 31, 2004: 19

Further information related to weekly beach postings can be accessed through the Health Unit's website at

FMLA There could be a number of reasons for the cause of eleveated E.coli levels at the public beach resulting in the single posting this year. In conversation with the Health Unit, it was said that fecal matter could have come from animals and fowl (dog, bear, bird (duck) etc.) on or near the ramp. Once the rains came, the heavy run-off, could have contaminated the sampling area.

Though sampling was correctly carried out, the initial June sampling was made from shore and not off the public dock as per usual; the dock was not in the water at that time.

The subsequent results for the balance of the summer indicate that FML has consistantly good water quality well below the 100 mark.

FMLA tried to obtain comparative data from other local lakes to show that FML has consistantly high quality conditions in the lake. However, these data were not made available by "press time".

[Original text prepared by: Haliburton Kawartha Pine Ridge District Health Unit]

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