Greenhouse growers' water practices under scrutiny

Thursday, May 26, 2011

by SUSAN MANN

An Ontario Environment Ministry study has concluded Leamington-area greenhouses are impacting local waterways.

Kate Jordan, ministry spokesperson, says environment officials saw increased phosphorous levels in local waterways because of the fertilizer products and irrigation practices growers use. But “there’s nothing in the study and in the data that we have to suggest there’s any type of immediate risk to the public.”

Instead ministry officials have “identified that greenhouses are having an impact so they need to take action to improve their operations,” she says.

The ministry worked with the local conservation authority to do the study in the Leamington area. The study was completed within the past year. The ministry has since been working with the greenhouse industry, growers and the local municipality “to make sure that we address the situation,” Jordan explains.

George Gilvesy, general manager of the Ontario Greenhouse Vegetable Growers, says “a strategic approach to dealing with issues pertaining to greenhouse production” was the focus of the industry’s work with the environment and agriculture ministries for more than a year. “Now we’re coming down to the implementation of what we think is the way to approach it,” he explains. “We want to continue to be treated as farmers. Our farmers want a farmer-friendly solution to this issue.”

The Ontario Ministry of Agriculture, Food and Rural Affairs is helping to develop and provide technical resources and information for growers says Annette Anderson, the ministry’s manager of greenhouse, agroforestry and specialty crop programs. It’s also developing a best management practices document and supporting research on effective water management and nutrient use.

“The greenhouse grower associations do take these types of issues very seriously,” she says, noting they’re working hard to promote and implement best management practices and plans.

Jordan says the environment ministry is taking an education and outreach approach. Ministry officials first shared the study with the municipality, the greenhouse industry and growers. “We wanted them to understand what we were finding, what our requirements were and what needed to be done to improve environmental performance.”

The ministry is also working with the industry to promote best management practices and improvements in operations, such as different ways for growers to handle their wastewater.

Jordan says most greenhouses have on site ponds to hold storm water. Growers often recycle irrigation water throughout their greenhouses but at some point the water can no longer be reused. That water is piped to an on site storage pond. But the vast majority of the ponds aren’t really built to be storm water management ponds. Rain and other factors cause the ponds to overflow and then they discharge directly into surface water.

“They’re not really designed for treating and holding wastewater,” she says. “To have a storm water pond and to discharge directly into the environment you do require approval from us.”

Jordan says most of the greenhouses in Essex County don’t have the required approvals for those ponds and growers don’t have measures in place to ensure the wastewater used in the greenhouse is being properly treated and handled.

“We’re working with them to make sure they understand what our requirements are and what they have to do to meet those.”

Several weeks ago, the ministry hosted meetings in the Leamington area for growers, greenhouse and municipal officials. The idea isn’t to target individual greenhouse operations, she says. Instead the ministry is working at the municipal level and with the industry to improve practices industry-wide.

The ministry is “not looking at putting in new burdens,” says Jordan. “We’re just looking at helping them improve their environmental performance to make sure they’re not impacting waterways.” BF