Water - 4.1 Water Quality

Poor quality water can transfer contaminants to livestock, poultry and food.

 

This good agricultural practice applies to all farms.

What Needs to Be Done

Reduce food safety hazards associated with contaminated water by ensuring water quality is suitable for its intended use.

How to Do It

Assess Water Source

Water quality for agricultural use varies depending on the:

  1. water source (e.g. river, stream, pond, ditch, lake, well, dugout or municipal, etc.), and
  2. usage of the water, (e.g. irrigation, crop washing, cleaning and sanitation procedures, or for livestock).

Water quality is a term used to describe the chemical, physical, and biological characteristics of water, usually in respect to its intended use.

Potable water means water provided by a domestic water system that meets the standards prescribed by regulation, and is safe to drink and fit for domestic purposes without further treatment.

Grey water is domestic wastewater that has been used to clean food or food contact surfaces. This used water is considered unfit for human consumption but may be recycled for an agricultural purpose that does not require potable water, such as washing a barn floor. Recycling this used water lowers the need for fresh water and puts less strain on an on-site septic system.

Wastewater contains both nutrients (for example, manure) and harmful contaminants, of which many are invisible. Contaminates of concern are:

  • pathogenic microbes like viruses, bacteria and parasites which can make both humans and animals sick, and
  • chemical contaminants from pesticides, petroleum-based products, heavy metals, and leachates. These are usually picked up by run-off water from a farm site.

Disposal of wastewater must follow both environmental and health legislation guidelines to ensure that wastewater is handled in such a manner as to protect other water sources, humans, and aquatic life.

Assess Intended Use

Cleaning & Sanitizing

  • Use potable water when cleaning and sanitizing food contact surfaces and for hand washing facilities.

Crops

  • For final washing, cooling and ice making use potable water (for example, the water complies with Canadian Drinking Water Quality Standards).

Canadian Drinking Water Standards:

E. coli: not detected in 100 mL water
Total coliforms: not detected in 100 mL water.

* Source: Health Canada, 2002. Guidelines for Canadian Drinking Water Quality – Summary Table.

For irrigation of crops eaten raw, use water that complies with the BC Ministry of Environment and Health Canada standards.

BC Ministry of Environment and Health Canada standards:

E. coli: <77 bacteria in 100 mL water;
Fecal coliforms: <200 bacteria in 100 mL water.

* Source: BCMAL, 2003. Treating Irrigation and Crop Wash Water for Pathogens. Factsheet #512.000-3.

For general irrigation, use water that complies with the Canadian Water Quality Guidelines for the Protection of Agricultural Water Uses.

Canadian Irrigation Water Standards:

Total coliforms: <1,000 bacteria in 100 mL water

* Source: Environment Canada, 2002. Canadian Water Quality Guidelines for the Protection of Agricultural Water Uses.

Livestock

There are no definite guidelines for the presence of microbes in livestock drinking water sources. Suggestions are given below:

Total bacteria: <10,000 per 100 mL, some reports suggest that total coliforms need only be <5,000 per 100 mL.

* Source: Agriculture and Agri-Food Canada, Prairie Farm Rehabilitation Administration

Canadian Water Quality Guidelines also have recommendations for heavy metals and pesticides levels for livestock drinking water.

Test Water Quality

  • Test water at the point of use ( for example, out of a tap, irrigation line), not at the source, because water can become contaminated by the time it reaches the point of use.
  • To test water for bacteria counts, contact an accredited laboratory. Here is a list of laboratories approved by BC Provincial Health Officer. [LINK BC Provincial Health Officer]
  • Water should be tested at least once a year. Frequency of water testing is dependent on water source and intended use.

Interpret the Results

  • When required, seek technical advice from various water, health and agricultural specialists.
  • When the results show a potential food safety hazard exists, stop using the water immediately. This source of water should not be used until it is properly treated and additional results confirm that the hazard no longer exists.
  • When water quality does not meet the requirements for the intended use, either treat water or find an alternate source.

Protect Water Sources

Be aware of sources of potential water contamination, such as upstream livestock, run-off, storm sewer overflows, or backflow of irrigation systems. Backflow prevention requirements are described in a BCMAL publication “Chemigation Guidelines for British Columbia”. The BCMAL Resource Management Branch’s Publications Series and BC Environmental Farm Plan Reference Guide can provide guidance to protect water sources and preserve water quality. See the “Useful references” section for more information.

Records to Keep

Lab-test results for water quality.

If You Need an Audit

Be prepared for the auditor to:

  • review water quality lab-test results,
  • review the frequency established for water testing, and
  • observe measures to protect water sources and preserve water quality.

Laws & Regulations that Apply

There are few specific laws that regulate the water quality to be used in agricultural production for food safety purposes. Generally, water quality in privately owned water systems for individuals is not specifically regulated by either the provincial or federal government, and individuals are responsible for ensuring their water is of good quality. However, requirements for very specific water quality standards are set out in laws regarding the processing of meat, fish and other food products, including egg-stations, as well as other services that deal with the public, which are outside the scope of this document. Laws to protect water quality are noted below.

 

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