The current SQF requirements and guidance are:
11.5.2 Monitoring and Water Microbiology and Quality
184.108.40.206 Water used for
....iii. cleaning food contact surfaces; .....
shall comply with local, national or internationally recognized potable water microbiological and quality standards as required.
11.5.2 Implementation Guidance
What does it mean?
Any water that is used in the process that could come in contact with the product must be verified to be in compliance with local and national standards.
In the US and Australia for example, the potability standard for drinking water is <1 coliform / 100 mL water and membrane filtration is the preferred method.
However, standards also apply for Salmonella spp, Shigella spp, enterovirulent E.coli, Vibrio cholera, Yersinia enterocolitica, Campylobacter jejuni, and protozoa.
220.127.116.11 Microbiological analysis of the water and ice supply shall be conducted to verify the cleanliness of the supply, the monitoring activities and the effectiveness of the treatment measures implemented. 18.104.22.168 Water and ice shall be analyzed using reference standards and methods.
11.5.6 Implementation Guidance
What does it mean?
Even though the water supply may come from the town or regional water supply in which the water is treated, safety tested and maintained by the local authority, it is required that food processers implement their own testing to ensure the safety of the potable water used within the facility.
What do I have to do?
The monitoring may involve one or a number of the following:
• Regular testing of water (e.g., pH, turbidity);
• Checking filtration apparatus and changing it as required (refer to supplier specifications);
• Regular cleaning of water holding tanks and reservoirs;
• Regular monitoring of sanitizer levels in water (levels normally tested at various sites in the food handling and processing areas).
Water should be tested at least every 12 months for potability and any additional quality or safety attribute. When utilizing an outside laboratory, seeking a laboratory that is properly accredited to complete the desired analysis is required.
So your water should be tested as a minimum annually for the organisms specified. These checks are for your water supply, note that it is also good practice to test water as close to the point of use as possible, this is to check the water isn't being contaminated in your distribution system.