Water, Water Everywhere

Is your irrigation water clean? Water treatment is becoming more necessary to ensure healthier plants.

by Michael Kovalycsik, National Sales & Marketing Director, Delta T Solutions

It’s the wettest known year in history. What are you doing to make sure your water quality is protected?

If you use city water and think your water supply is fine because your municipality already cleans and treats it, be warned that presumption is not necessarily true.

Young plants are susceptible to waterborne diseases, and sediment in water often clogs systems up, causing problems with plant health. As more growers recapture and reuse irrigation water, there is a growing need for more education on water treatment.

WATER RESEARCH REVEALS DIRTY WATER

In a Young Plant Research Center study completed in summer 2009 by then Ph.D. candidate Dustin Meador and Dr. Paul Fisher of the University of Florida, water samples were collected from 24 greenhouses and nurseries across 11 states. The samples were evaluated for physical, chemical and biological water quality to determine whether current practices were maintaining water quality within guidelines recommended by the Environmental Protection Agency (EPA). These were the results:

Physical Properties:

• Suspended solids were below the EPA-recommended range for non-edible crops.

• Ultraviolet light transmission was above the recommended minimum in all but one source sample.

Chemical Properties:

• Water alkalinity ranged widely among sources, showing the need for acid injection in many locations to neutralize it, as high water alkalinity often causes gradual increase of growing medium pH.

• Water pH was above 7.5 in more than half of the greenhouse and nursery locations, indicating a need to inject acid when using chemicals like copper ionization or clorine to improve sanitizing power.

• Electrical conductivity (EC) was low in source water, which showed need for reverse osmosis or water source blending at a few locations.

Biological Properties:

• Only 10% of source samples exceeded bacteria counts, but high levels of bacteria were found in other parts of irrigation systems.

• Most bacteria found in irrigation is often benign or even beneficial, high bacteria counts indicated a need for sanitizing agent like chlorine to control biofilm build-up in the system; however, sanitizer may be less effective against disease pathogens like Pythium.

As the survey indicates, irrigation water has more swimming in it than you think.

SUBIRRIGATION IMPROVES PLANT QUALITY

Many growers are adopting subirrigation systems in their greenhouses, due to the many benefits it offers, including quick ebb and flow watering on specially shaped floors and benches for plants in pots or cell packs.

Delta T Solutions’ flood floor and bench packages are tailored to meet operational needs. The Flood and Bench Irrigation Line provides high levels of quality and reliable performance in both flood floors and benches. It works with many crops; waters evenly, resulting in uniform plant growth; and minimizes the risk of disease and produces no runoff, which means no pollution. Water, fertilizer and sanitizer chemicals are not wasted and subirrigation promotes good sanitation. Systems like these are reliable and low-maintenance, offering excellent payback in crop quality, ease of operation and environmental compliance.

Implement water quality Best Management Practices, such as this compost filter berm, at your greenhouse operation.

GO GREEN, USE RAINWATER

With this year’s record precipitation, think about implementing rainwater collection systems. This is popular among home gardeners and is available in large-scale systems for commercial operations. It can be used to either supply additional water to the greenhouse system or to replenish an underground aquifer. You can also reduce environmental impact by capturing and reusing runoff, which is accomplished easily using recirculating irrigation systems.

Prevent runoff and protect water quality by implementing the U.S. Environmental Protection Agency’s stormwater best management practices and learn more about the importance of protecting ground water.

Delta T Solutions has decades of experience developing high-quality irrigation systems to provide you with the cleanest irrigation water possible. We will work with you to develop a custom greenhouse water treatment system and tail water runoff control collection system. Contact a Delta T Solutions Representative to learn more by calling 800-552-5058 or email: info@deltatsolutions.com.