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New Greenhouse Regulation Supporting Sustainability

Archived Backgrounder

New Greenhouse Regulation Supporting Sustainability

As of January 1, 2015, the new Greenhouse Nutrient Feedwater Regulation will allow the land application of greenhouse nutrient feedwater (GNF) under the Nutrient Management Act.  The regulation provides eligible greenhouse growers with a new option to manage GNF in a way that enhances the protection of the natural environment and supports the sector's sustainability through a streamlined approval process.

Supporting the 3Rs and making the best use of a resource 

Many greenhouse operations use circulation systems to deliver water and fertilizer as a nutrient solution to greenhouse crops that are grown without the use of soil. After reusing multiple times, the excess solution may no longer be optimal for growing greenhouse crops, but can still have nutrient value suitable for other agricultural crops and can be recycled on agricultural lands to support plant growth.

The new regulation supports the greenhouse sector's efforts towards improving compliance by adding to the toolbox of options available to properly manage this greenhouse material:

  • Reduce excess nutrient solution by applying best management practices within the greenhouse;
  • Reuse nutrient solution by optimizing recirculation within the greenhouse;
  • Recycle nutrient solution that cannot be recirculated by applying to crops grown on agricultural lands; and
  • If necessary, responsible disposal under the Ontario Water Resources Act or the Environmental Protection Act.

GNF benefits local farmers by providing a new source of inexpensive nutrients that can reduce the need for expensive commercial fertilizers and by providing supplemental irrigation water that can replace water drawn from lakes, rivers and wells.

Protecting the environment

The regulation protects surface water, groundwater and soil by setting out a framework for managing, storing and land applying GNF. This framework requires:

All participating greenhouse operations to register,

  • The development of management strategies for adequate and  safe storage where needed,
  • Approval of plans for land application,
  • Tracking of the proper transportation of greenhouse nutrient feedwater to agricultural operations,
  • Sampling of greenhouse nutrient feedwater and soil, and
  • Training for famers, transporters and crop advisers who work with greenhouse nutrient feedwater.

The regulation supports Ontario's Great Lakes Strategy, 2012, to reduce nutrient inputs to the environment. It will be complemented by an approval exemption for sewage works managing GNF under the Ontario Water Resources Act and consequential amendments to the general waste management regulation under the Environmental Protection Act.

One more tool in greenhouse operators' toolbox

With this new addition, greenhouse growers have another tool they can use to comply with environmental standards. All options available to greenhouse operations under the Nutrient Management Act (NMA) or Ontario Water Resources Act (OWRA) / Environmental Protection Act (EPA) frameworks now include:

  • Reuse of nutrient feedwater in a greenhouse;
  • Application on land under NMA;
  • Application on land under Environmental Compliance Approval;
  • Treatment and discharge using a sewage works under Environmental Compliance Approval;
  • Disposal off-site by approved waste hauler to an approved waste disposal site; and
  • Discharge to sanitary sewer.

The Ministry of Environment and Climate Change is responsible for enforcing compliance with the Ontario Water Resources Act, the Environmental Protection Act and the Nutrient Management Act.

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