This page explains what the rule means for Ontario farmers planning barn construction, livestock expansion, manure storage, or nutrient application.
What Is the Nutrient Management Act?
The Nutrient Management Act, 2002 (NMA) is Ontario's primary legislation governing how nutrients — mainly livestock manure, but also biosolids and other non-agricultural source materials — are managed on agricultural operations across the province.
The Act was created to protect Ontario's water, soil, and air from the environmental risks associated with nutrient generation, storage, and land application. It provides the legal authority for the Province to require plans, strategies, and approvals before farmers build barns, expand livestock operations, or apply certain materials to their land.
For any Ontario farmer planning a construction project, livestock expansion, or changes to manure handling, this Act is the starting point. Understanding it is essential to avoiding costly delays and compliance issues.
What the Act Regulates
The Nutrient Management Act establishes the regulatory framework for the entire lifecycle of nutrients on Ontario farms:
Generation of nutrients from livestock operations (manure, bedding, washwater)
Storage of manure and other prescribed materials
Land application of nutrients, including rates, timing, and methods
Use of non-agricultural source materials (NASM) such as biosolids and food processing waste
Construction and expansion of agricultural buildings that house livestock or store manure
Transfer and transportation of nutrients between operations
Key Takeaway: The Act doesn't just cover manure spreading — it covers the entire chain from barn to field, including how nutrients are generated, stored, and ultimately applied.
Key Definitions Under the Act
The Nutrient Management Act establishes the regulatory framework for the entire lifecycle of nutrients on Ontario farms:
Generation of nutrients from livestock operations (manure, bedding, washwater)
Storage of manure and other prescribed materials
Land application of nutrients, including rates, timing, and methods
Use of non-agricultural source materials (NASM) such as biosolids and food processing waste
Construction and expansion of agricultural buildings that house livestock or store manure
Transfer and transportation of nutrients between operations
Nutrient
Under the Act, a "nutrient" includes any material that can be applied to land as a source of plant nutrition. This encompasses livestock manure, compost, biosolids, septage, and other non-agricultural source materials. The definition is deliberately broad to capture all materials that could impact soil and water quality.
Nutrient Management Strategy (NMS)
An NMS is a document required before constructing or expanding livestock housing or manure storage. It addresses how nutrients generated on the farm will be managed — including storage capacity, land base requirements, and compliance with Minimum Distance Separation (MDS) setbacks. An NMS must be approved by OMAFRA before a building permit can be issued.
Nutrient Management Plan (NMP)
An NMP addresses how nutrients are applied to land. It is required for operations generating 300 or more nutrient units, or when triggered by an NMS approval. The plan specifies application rates, timing, and methods to ensure nutrients are applied responsibly and within regulatory limits.
Regulatory Authority
The Nutrient Management Act grants the Province of Ontario broad regulatory authority over nutrient management practices. Specifically, the Act empowers the government to:
Create detailed regulations prescribing standards, practices, and requirements
Require preparation and submission of nutrient management strategies and plans
Appoint provincial officers to inspect farms and enforce compliance
Issue orders, impose administrative penalties, and prosecute offences
Establish nutrient unit thresholds that trigger regulatory requirements
The Act itself sets out the broad framework. The detailed, day-to-day rules that farmers must follow are found in the regulations made under the Act — most importantly, Ontario Regulation 267/03.
Relationship to O. Reg. 267/03
One of the most common sources of confusion is the relationship between the Nutrient Management Act and Ontario Regulation 267/03. Here's how they work together:
The Act (NMA, 2002)
The framework. It establishes the legal authority, defines key terms, sets out the power to make regulations, and provides for enforcement. Think of it as the foundation.
The Regulation (O. Reg. 267/03)
The rules. It prescribes the specific requirements — nutrient unit thresholds, storage standards, setback distances, plan content, and submission processes. This is where the practical requirements live.
In Practice: The rules. It prescribes the specific requirements — nutrient unit thresholds, storage standards, setback distances, plan content, and submission processes. This is where the practical requirements live.
Approvals and Compliance
The Act establishes the approval framework that farmers must navigate. Depending on your operation, you may be required to:
Submit a Nutrient Management Strategy (NMS)
Required before constructing or expanding a livestock barn or manure storage facility. Must be approved by OMAFRA before a municipal building permit is issued.
Prepare a Nutrient Management Plan (NMP)
Required for phased-in operations generating 300 or more nutrient units, or when triggered as a condition of an NMS approval. Filed with OMAFRA.
Obtain a NASM Plan Approval
Required before applying non-agricultural source materials (biosolids, septage, food processing waste) to farmland. Approved by OMAFRA.
Enforcement and Penalties
The Nutrient Management Act includes strong enforcement provisions. Understanding these is important for every farm operator:
Provincial Officers
The Act authorizes the appointment of provincial officers who have broad powers to enter agricultural operations, conduct inspections, take samples, and issue compliance orders.
Inspections
Officers may inspect your operation without a warrant to verify compliance with the Act and its regulations. This includes reviewing records, plans, and physical infrastructure.
Administrative Penalties
The Act provides for administrative monetary penalties (AMPs) for non-compliance. These can be issued without a court proceeding and are separate from prosecution.
Strict Liability
Many offences under the Act are strict liability offences — meaning the Crown does not need to prove intent. If a violation occurred, the farmer bears the burden of demonstrating they exercised due diligence to prevent it.
Many offences under the Act are strict liability offences — meaning the Crown does not need to prove intent. If a violation occurred, the farmer bears the burden of demonstrating they exercised due diligence to prevent it.
Interaction with Other Legislation
The Nutrient Management Act does not operate in isolation. It interacts with several other Ontario statutes that may apply to your operation:
Environmental Protection Act (EPA)
The EPA applies broadly to environmental contamination. If manure or nutrients cause an "adverse effect" — such as contaminating a neighbour's well — the EPA may apply in addition to the NMA.
Ontario Water Resources Act (OWRA)
The OWRA prohibits the discharge of materials that may impair water quality. Improper manure storage or application near watercourses can trigger liability under this Act as well.
Key Takeaway: Compliance with the Nutrient Management Act does not automatically mean compliance with all environmental legislation. Multiple statutes may apply simultaneously.
Practical Implications for Farmers
Here's when the Nutrient Management Act is most likely to affect you:
You are building a new barn or expanding an existing one
You are increasing the number of livestock on your operation
You are constructing or modifying manure storage
Your operation generates or will generate 300 or more nutrient units
You are applying non-agricultural source materials (NASM) to your land
You are purchasing a farm with an existing nutrient management obligation
You are changing your livestock type in a way that increases nutrient generation
Tip: If you're unsure whether the Act applies, it's better to check early. Discovering a requirement after construction has started can delay your project by an entire growing season.
Common Misunderstandings
"The Act only applies to large farms."
Not true. Any farm that builds or expands livestock housing may trigger the requirement for an NMS — regardless of size. The 300 nutrient unit threshold is only one of several triggers.
"I only need a plan if I spread manure."
An NMS is about generation and storage, not application. You can trigger a requirement simply by building a barn — even if you export all your manure.
"My municipality handles everything."
Municipalities issue building permits, but they cannot issue one for livestock housing until OMAFRA has approved the required NMS. The provincial process is separate and must happen first.
"I can sort out the paperwork after I start building."
The Act requires approvals before construction. Starting without them risks orders to stop work, penalties, and having to retrofit or relocate structures.
Why This Act Matters When Building a Barn
Barn construction is one of the most common triggers for the Nutrient Management Act. When you build or expand a livestock barn in Ontario, you are increasing the nutrient generation capacity of your operation — and the Act requires that this be addressed before construction begins.
Specifically, you will need to demonstrate:
Adequate manure storage capacity for the proposed operation
Compliance with Minimum Distance Separation (MDS) setbacks
Sufficient land base for nutrient application (or confirmed export agreements)
That the proposed operation will not cause an adverse effect
You are applying non-agricultural source materials (NASM) to your land