myOFA - Water Treatment Resources
Prepared by Paul Fisher, Associate Professor and Extension Specialist, University of Florida

As part of the ongoing focus on water quality by OFA and the Young Plant Research Center, we are developing resources to help growers make informed decisions on monitoring and control of waterborne pathogens and contaminants. We have prepared a preliminary list of links to articles, people, and companies working on water quality and treatment, and encourage your contributions. To add links to this list, or to correct errors, please contact pfisher@ufl.edu.

CONTROL TECHNOLOGIES FOR DISINFECTING IRRIGATION WATER
Links in this section include a presentation and handout by Dr. Steven Newman from Colorado State University, who provides a clear overview of control options. Dr. Newman also provides information about Oxidation Reduction Potential (ORP) and its relationship to oxidizing chemicals such as chlorine or hydrogen dioxide. References by Ehret and others (Canadian and European researchers) and van Os provide an international perspective and interesting insights: "it is perhaps not right to kill all life in the solution, there is a certain microflora present playing its role in suppression of diseases".

Disinfecting irrigation water for disease management. Newman, Colorado State Univ. 2004.

Powerpoint presentation on disinfecting irrigation water for disease management. Newman. Colorado State University. 2005.

Research overview of disinfestation of recirculating nutrient systems. Ehret et al., Agronomie scientific journal. 2001.

Three part water quality series. Roseman, Aqua Ion Plus+ Technologies. 2002. See also related article links at the following Water Quality Products magazine site.

Perspectives on treatment options. Powell, Plant Health Advisory Services. GrowerTalks.

Bio-Sand Filtration. British Columbia Ministry of Ag, Food, and Fisheries. 1999.

Chlorine treatment of irrigation water. Clark and Smajstrla. University of Florida. 2006.

Chlorine dioxide and algae. Konjoian, Konjoian's Floriculture Education Service and Merrill, Selective Micro Technologies. 2005. OFA Bulletin (www.ofa.org/myofa.aspx, select OFA Bulletin Archive, July/Aug 2005).

BIOLOGY OF PATHOGENS
Dr. Hong provides specific data on dose response of Pythium and Phytophthora to chlorine, including research funded by the FIRST organization. Dr. Wick provides a good overview of waterborne pathogens.

Pythium and Phytophthora in irrigation water (including chlorine sensitivity). Hong et al. Virginia Polytechnic Institute. 2003.

Biology, spread, and survival of waterborne pathogens. Wick. 2006. Univ. of Massachusetts. OFA Bulletin (www.ofa.org/myofa.aspx, select OFA Bulletin Archive, March/Apr 2006).


GREENHOUSE SANITATION
Controlling waterborne pathogens is only component in reducing disease risk – basic sanitation is a key. Dr. Tina Smith provides common sense steps to sanitation, and reviews disinfectants available to growers.

Cleaning and disinfecting the greenhouse. Smith. Univ. of Massachusetts. 2006.

MONITORING
Dr. Newman provides information on onsite testing of pH, EC, ORP, and chlorine. Dr. Mylavarapu provides an overview of the main parameters in water quality tests, and Dr. Yeager provides guidelines on how to collect water samples for onsite or laboratory testing.

Powerpoint presentation on onsite water quality testing. Newman. Colorado State University. 2005.

Irrigation and Household Water Test and Interpretation. Rao Mylavarapu, University of Florida. 2004.

Collecting water samples for testing. Yeager, University of Florida. 2003.

WATER QUALITY, CONTAMINANTS, AND NUTRITION
These links provide detailed information on water quality tests for greenhouse and nursery growers, with an emphasis on salt levels, pH, alkalinity, and contaminants.

Understanding water quality (series, emphasizing salts and nutrition). Argo, Blackmore Co. and Fisher, Univ of New Hampshire. 2003. OFA Bulletin (www.ofa.org/myofa.aspx, select OFA Bulletin Archive, May/June 2003, July/Aug 2003, Nov/Dec 2003)

Water quality and alkalinity (several articles). Bailey et al. North Carolina State Univ. 1998 and later.

Foliar Deposits and Stains from Irrigation Water. Haman and Yeager. University of Florida. 2000.

Removing contaminants from recycled water. Kovach. Kinetico Inc., GPN magazine article. 2000.

POLLUTION AND RUN OFF
Runoff from greenhouses and nurseries are being increasingly regulated and the University of Georgia site is an example of how universities are focusing on best management practices to minimize potential for pollution. The site by Dr. Yeager is full of practical technical advice, including information on how to improve irrigation efficiency. 

Pollution prevention in greenhouses (best management practices). Panter, Newman and Waskom. Colorado State Univ. 1999.

How to run a water audit: assess water sources, quality, and technology at your site (Greenhouse*A*Syst program). Thomas et al. Univ. of Georgia. 2005.

Maximizing fertilizer and minimizing runoff. Dole and Cole. North Carolina State Univ.

Irrigation publications for nursery growers. Yeager and others, University of Florida.

INJECTOR SYSTEMS
For any oxidative or acid materials injected into the irrigation system, maintenance and correct selection of an injector is essential. I also suggest looking at websites for injector manufacturers (Anderson, Dosatron, Dosmatic, and others).

Dilution rates. Clark et al. University of Florida. 2005.

Chemical injection methods. Haman et al. University of Florida. 2003.

SOME COMPANIES PRODUCING WATER QUALITY PRODUCTS
This list is inevitably very incomplete, and please contact Paul Fisher with other related company websites.

Accu-Tab System/PPG Industries (tablet chlorination system): www.ppgaccu-tab.com

Aqua Ion Plus+ Technologies (water treatment systems): http://aquaionplus.com

Argus Control Systems (water treatment, irrigation, and nutrient controls) www.arguscontrols.com

BioSafe Systems (ZeroTol hydrogen dioxide algaecide/fungicide): www.biosafesystems.com

Chemilizer (Water powered, chemical injectors): www.chemilizer.com

Dosatron (injectors): www.dosatron.com

Dosmatic (injectors): www.dosmatic.com

Fischer EcoWorks (water treatment system design): www.fischerecoworks.com

H.E. Anderson (injectors): www.heanderson.com

HortiMaX (environmental, irrigation and nutrient controls): www.qcomcorp.com

Priva North America (high-pressure UV disinfection with Priva Vialux): www.priva.ca

Pure-O-Tech, Inc. (water treatment systems): http://pureotech.com

Selective Micro Technologies (Selectrocode chlorine dioxide disinfectant/sanitizer/fungicide/algaecide): www.selectivemicro.com

Trueleaf Technologies (water treatment and management systems): www.trueleaf.net

REFERENCE LISTS, BOOKS, AND JOURNALS
Water and Nutrient Management for Greenhouses, NRAES-56. Weiler and Sailus (ed.)

Preventive Control Measures for Microbial Hazards on Fresh and Fresh-Cut Produce. U. S. Food and Drug Administration. 2001.

Water resource fact sheets. Colorado State Univ. 2006.

International symposium on greenhouse water quality & quantity. International Soc. of Hort. Science. 1998.

Greenhouse Product News water quality archives: www.gpnmag.com, select "Archives - Articles" and "Water quality/irrigation". See also archives under Water Quality Products magazine also from Scranton Gillette Interactive Media (www.wqpmag.com/).

International Water Association list of journals.

UNIVERSITY RESEARCHERS WORKING ON WATERBORNE PATHOGENS AND WATER TREATMENT
Water quality is an active area of research in both universities and industry. Here is a partial list of academics working on water treatment in the U.S.

Robert Berghage (artificial wetlands), Pennsylvania State University.
http://hortweb.cas.psu.edu/dept/faculty/berghage/berghage.html

Margery Daughtrey, Cornell University.
http://www.plantpath.cornell.edu/Directory/Faculty_Info/Daughtrey.html

Chuanxue Hong, Virginia Technical Institute and State University.
http://ipm.ppws.vt.edu/faculty/hong.html

Gary Moorman, Pennsylvania State University.
http://www.ppath.cas.psu.edu/FACULTY/moorman.htm

Steven Newman (monitoring, technology), Colorado State University.
http://ghex.colostate.edu/flor_faculty/newman/index.htm

Robert Wick, University of Massachusetts.
http://www.umass.edu/psis/personnel/wick.html