It depends on their water uses and what is being done to the water. If water is used for a final rinse, then it needs to be tested, as the result is used to see if the equipment itself is clean. If water is treated, then it must be tested to determine that the treatment is working. If water is stored, then it must be tested to ensure that the storage vessel is not a source of contamination. If water is being used for humidity/misting or post-harvest applications of agricultural chemicals, it must be tested from the equipment itself to ensure it is clean. Otherwise, a test is unnecessary; it is assumed the municipality is doing its job providing potable water. If the municipality advises of an adverse water event, this is treated as a deviation and the operation must take appropriate corrective action (e.g., use alternate source, treat water, test water, etc.).
For countries other than Canada, refer also to the next question.