Drinking water quality
The Government Laboratory has a wide range of both chemical and microbiological test methods in place to enable the assessment of the quality of water and its suitability for drinking.
Routinely applied tests include looking for the presence of common bacteria that can cause illness or which indicate inadequate purification of the water, contamination by metallic impurities that might be leached from the ground in areas from which the water is drawn, and abnormalities such as acidity or excessive residue of chemicals from treatment processes.
Other tests may be applied from time to time in the event of any specific problem being identified or suspected.
Public water supply
As public analyst for the Isle of Man, the Government Analyst has a statutory duty to sample and analyse the public water supply to assess its quality.
On the Island the public water supply is provided by the Isle of Man Water and Sewerage Authority, to 7 defined supply areas. Drinking water is sampled on a regular basis by the Government Laboratory's staff from consumers' own taps in each of the supply areas and taken back to the laboratory for assessment of its chemical and microbiological quality. Any failure to meet EU water quality requirements results in notification to the Water and Sewerage Authority, and further investigation to verify that any problem is resolved.
In addition, since closure of their own testing laboratory a full routine analytical service has been provided to the Water and Sewerage Authority, providing essential microbiological and chemical data on the supply water at its various stages of production and treatment to enable the authority to check that its processes are working satisfactorily and to identify any problems with quality or contamination at an early stage.
Private water supply
Some properties are not connected to the mains public water supply, instead having private water supplies, for example from boreholes. These are sampled periodically, usually by Environmental Health Officers, and submitted to the Government Laboratory for assessment of chemical and microbiological quality, following which a report is issued identifying any deficiencies found.
Water sold in containers is covered by the requirements of the Food Act 1996 and subordinate legislation, and may be sampled by Environmental Health Officers for analysis at the Government Laboratory to verify that it complies with all relevant requirements, including any claims made on the label or in any advertising.