What is the minimum distance separation formula and how does it affect building near a livestock operation in Ontario?

Minimum distance separation, usually called MDS, is a formula-based planning tool Ontario municipalities use when deciding how close new development can be sited to an existing livestock operation, and how close a new or expanding livestock facility can be sited to existing homes and other land uses. Rather than a single fixed number of metres, it's calculated using factors specific to the operation, such as the type and size of the livestock facility and how manure is stored and managed, to produce a setback distance meant to reduce conflict between farming and other land uses.

This formula gets applied through the municipal planning process under Ontario's land use planning framework, so it typically comes up when a landowner applies to sever a lot, build a new dwelling, or expand a barn near an existing farm, rather than as something a private buyer calculates independently. A rural buyer looking to build near an established livestock operation, or a farmer looking to expand near residential development, should raise MDS with the municipality and their planning or legal advisor early in the process, since it can significantly limit where a building can actually be placed, or block a severance or building permit outright if the required separation can't be met on the available land.