Greenhouse wastewater discharges provoke legislation debate

Friday, May 18, 2012

by SUSAN MANN

Ontario’s Environmental Commissioner Gord Miller questions whether the Nutrient Management Act can be used for wastewater discharges from greenhouses, an idea Ontario’s horticultural sector recently proposed to the provincial government. Currently, anyone discharging more than 10,000 litres of water a day must get an Environmental Compliance Approval from the environment ministry, which the industry describes as an onerous and expensive process.

The Act isn’t about discharges to waterways “it’s about the proper management of manure and spreading manure on agricultural land,” says Miller, the province’s independent environmental watchdog.

The government would have to pass an entirely new Nutrient Management Act “which identified water discharges from greenhouses not as sewage works under the Ontario Water Resources Act. They would have to change that whole structure of the Act,” he says.

The commissioner made the comments during an interview about a Ministry of the Environment study in Essex County, Greenhouse Wastewater Monitoring Project, 2010 and 2011, released this month. Policy-making is not a part of his role and he is not a member of the provincial environment ministry, which published the study.

The study found many greenhouses discharged wastewater containing high levels of phosphorous into nearby creeks that flow into Lake Erie. In particular, environment ministry water quality monitoring from greenhouse outfalls found greenhouse discharge to be responsible for direct degradation of the water quality in Sturgeon Creek and Lebo Drain. “They are the most polluted waterways in Ontario with respect to phosphorus and nitrate and in the top five most polluted with respect to potassium and copper,” the study’s summary claims.

In a May 9 press release, the Ontario Greenhouse Vegetable Growers says farmers are concerned about the wastewater test results. Growers consider it important to protect water quality because they live on or near properties containing their greenhouses and depend on that water for their families and crops.

The industry wants to be accountable for its actions and take whatever steps are necessary to reduce its impact on the environment. That’s why the association formally requested in January that the greenhouse sector be under the Nutrient Management Act, “which we believe to be the best approach to improve environmental performance while maintaining the competitiveness of our farms,” the release says.

George Gilvesy, general manager of the Ontario Greenhouse Vegetable Growers, explains greenhouse agriculture is currently listed in the definitions section of the Nutrient Management Act. When the government passed the Act, “our belief is the intention of government at the time was to involve other forms of agriculture.”

Being under the Nutrient Management Act doesn’t mean the greenhouse sector would be exempt from the Water Resources Act. “It just means that it deals with things in an agricultural perspective with agricultural solutions for farmers,” he says.

Mark Cripps, spokesman for Ontario Agriculture Minister Ted McMeekin, says the agriculture and environment ministries are reviewing the requests and plan to the report back to the sector this summer. The Ontario Fruit and Vegetable Growers Association has also asked the government to draft regulations under the Nutrient Management Act to govern wash water from produce on farms and implement a moratorium on the environment ministry requiring farmers to get their compliance approvals until the new regulations are in place.

Another point of concern for the greenhouse growers is the study’s conclusion that the environment ministry can’t support further greenhouse development in the Leamington and Kingsville areas unless appropriate wastewater treatment technology is implemented.

Ministry spokesperson Kate Jordan says they’ve inspected all of the greenhouses in the Leamington and Kingsville areas and talked to growers about their rules and what they need to do to comply with the ministry’s approval requirements.

“We’re helping them come up with plans to come into compliance,” she says.

Gilvesy questions what the ministry considers to be “appropriate” wastewater treatment technology. “Everyone’s working on solutions,” he says. “It’s a global problem.”

He says the greenhouse association has been working with the agriculture and environment ministries for the past 18 months on a strategic approach to the situation after the environment ministry released preliminary results of their study to the industry. One part of their work involves developing education programs and materials for farmers, including a detailed set of Best Management Practices for water use. Development of the practices is under the oversight of the agriculture ministry and is almost completed.

The greenhouse association has also been doing research to “develop improved technology and practices,” Gilvesy says. “A number of those projects involve selective membrane filtration” and use of proper systems to match fertilizer applications with crop requirements. The greenhouse association’s board also approved a policy statement encouraging members to “move towards recycling their nutrients.”

The greenhouse vegetable growers association represents about 223 Ontario greenhouse vegetable growers producing 2,067 acres of tomatoes, peppers and cucumbers. In 2011, the farm gate revenue for the Ontario greenhouse vegetable industry was worth more than $698 million.

In its release, the environment ministry says phosphorus is harmful because it’s a major contributor to algae blooms that foul beaches and are sometimes toxic. The summary notes phosphorous discharges from greenhouse outfalls are significantly compromising Ontario’s commitment in water quality agreements with the United States to achieve point source reduction of phosphorus. BF