Water Quality Testing Methods

All samples were analysed according to the American Public Health Association's (APHA) Standard Methods for the Analysis of Water and Wastewater, 21st edition.

Sites

Routine sampling is carried out at the below specified sites during the months of August, October, November, December, January, February, March and May. Beach sampling is carried out weekly between the second week of October and the mid week in April, however this can be varied according to the needs existing at the time.

Midstream Sites

  • LBG529 – East Basin. Due to the shallow depth of water all analysis at this site is carried out on samples taken at approximately 0.3m below the water surface. These samples are considered surface samples.
  • LBG530 – Central Basin. The microbiological samples are collected from the surface, while the chemical and biological samples are collected using a purpose-built tube sampler. The tube depth is at least 0.5m off the bottom, and a maximum of 5 metres in depth.
  • LBG504 – West Lake. The microbiological samples are collected from the surface, while the chemical and biological samples are collected using the tube sampler. The tube sample is 5 metres in depth.
  • LBG507 – Scrivener Dam. The microbiological samples are collected from the surface, while the chemical and biological samples are collected using the tube sampler. The tube sample is 5 metres in depth.
  • LBG505 – West Lake (2). The microbiological samples are collected from the surface, while the chemical and biological samples are collected using the tube sampler. The tube sample is 5 metres in depth (site added April 2009).

Beach Sites (Designated Recreational Sites)

  • LBG512 – Boathouse – East Basin – Secondary contact
  • LBG511 – Ferry Terminal – West Basin – Primary contact
  • LBG510 – Lotus Bay – West Lake – Secondary contact
  • LBG514 – Yarralumla Beach – West Lake – Primary contact
  • LBG516 – Weston Park East – Tarcoola Reach – Primary contact
  • LBG515 – Black Mountain Beach – Tarcoola Reach – Primary contact
  • LBG517 – Weston Park West – Yarramundi Reach – Primary contact
  • LBG532 – Rond Terrace – Central Basin – Secondary contact (added February 2011)
  • LBG533 – Yarralumla Beach - West Lake - Secondary contact (added January 2016)

Water Temperatures

Measurements are taken of water temperature at each site by calibrated thermometer concurrently with the collection of beach water samples.

Sample Sheets

A sample-reporting sheet is used to record the presence/absence of blue-green algae by visual inspection, evidence of stormwater discharge from nearby (obvious) piping and noting the presence of any surface scums or discharge at each site. Note is also taken of any noticeable odours occurring at the sampling site, and anything else that might be considered unusual.

Chemical and Biological Analysis of Samples

Standards/Accreditation

All tests are to be National Association of Testing Authorities (NATA) accredited with accreditation number. All procedures and quality assurance within the laboratory are based on AS/NZS ISO 9002 standards, and have to have been recently audited under the NATA Guide 17025 standard.

Testing Regime

There is a combination of chemical, microbiological and biological testing done at each site, since an assessment of water quality, especially in open environmental waters such as this, must be based on the results of comprehensive data analysis.

The beach sites are routinely monitored for temperature, dissolved oxygen, and intestinal enterococci, although additional testing is carried out on some samples.