Janice LeBoeuf, OMAFRA Vegetable Crop Specialist, Ridgetown
A number of educational resources on water quality and monitoring (for irrigation or postharvest) can be found on the website of the Water Education Alliance for Horticulture. Browse them here: http://www.watereducationalliance.org/education.asp.
If you scroll down and click on Monitoring, you will find an excellent video explaining ORP (oxidation-reduction potential) and how it affects water sanitizers such as chlorine. This is important for postharvest dump tanks and washing.
There are other useful resources on irrigating, water quality, and monitoring throughout the website. Technical articles can be found at http://www.watereducationalliance.org/techlinks.asp and http://www.watereducationalliance.org/irrigationlinks.asp.
The Water Education Alliance for Horticulture is a partnership between universities and industry designed to help growers use water efficiently and sustainably. Their goal is to provide growers with information on water treatment and to fill informational gaps on technology efficacy.