Calculating designated greenfield area densities

The calculation of designated greenfield area densities, a challenging task at best, is further complicated by the different methods used by each upper- and single-tier municipality. The Province has not stipulated a standardized method for these calculations.

What is meant by 50 people and jobs combined per hectare (p+j/ha)? It is not simply a matter of dividing the number of people and jobs in a given area by the total land base. Rather, the Growth Plan specifies certain areas and features on which development is not permitted, and requires municipalities to exclude these areas from the density calculation.[1] These areas and features (sometimes called "takeouts") include provincially significant woodlands, wetlands, valley lands, fish and wildlife habitat, and areas of natural and scientific interest. So, for example, an area of 10 hectares that contains a 3-hectare provincially significant wetland is considered as 7 hectares of greenfield land for the purposes of the density calculation. If 300 people and jobs occupy this area, the density is calculated as 300 divided by 7, or 42.8 people and jobs per hectare.

In addition to the features specified in the Growth Plan, there are many other types of land and features on which development is not feasible or permitted, ranging from railways easements and hydro corridors to cemeteries, golf courses, and buffer areas around significant natural features. If those other areas are also excluded from the calculation, the apparent greenfield area density level rises. For example, if in addition to a 3-hectare wetland, the greenfield area mentioned in the previous paragraph contains a 1-hectare cemetery and a 2-hectare hydro corridor, the area of designated greenfield area for the purposes of the density calculation is considered to be only 4 hectares. If 300 people and jobs occupy this area, the density can now be calculated as 300 divided by 4 or 75 p+j/ha, instead of 42.8 p+j/ha.

Figure 3.7 shows how, using one method of calculating greenfield density, accommodating 15,000 people and jobs on 1,000 total hectares leads to a calculated density of 23 p+j/ha, while another method yields a density figure of 50 p+j/ha. Yet the same number of people are accommodated on the same amount of land in both cases. The difference lies in how much designated greenfield area land is excluded from the density calculation.[2]

Figure 3.7: Calculating designated greenfield area density

This is not an academic exercise; these "takeout" numbers matter. Consider the example in Figure 3.7 above. Municipality B, represented by the right side of the figure, uses the density calculation to demonstrate that it has achieved the requirement of 50 p+j/ha. Municipality A, however, would have to increase the number of people and jobs that are planned in the area in order to meet the same requirement. To achieve a density of 50 p+j/ha on 650 hectares of land, it would need to plan for 33,000 people and jobs in the overall area - more than twice as many people and jobs as Municipality B.

Furthermore, if Municipality B needs to plan for a forecast population of more than 15,000, it may use these figures to argue for an expansion to the urban boundary to increase the amount of land designated for development. The municipality could justify the expansion on the basis of having met the requirement for accommodating 50 people and jobs on the available greenfield land. Therefore the method of calculating designated greenfield area densities has important implications for the amount of land that will be urbanized to accommodate forecasted growth.

Municipalities that exclude more land from the density calculation are effectively able to develop designated greenfield area land at overall lower densities compared with municipalities that exclude only the areas and features specified in the Growth Plan. The four regional municipalities in the Inner Ring have all elected to use more "takeouts" than those specified in the Growth Plan. In the Outer Ring, Waterloo Region has chosen to use only those "takeouts" indentified in the Growth Plan, while Niagara is using some addition "takeouts" beyond those in the Plan. The approaches taken by the other upper-tier municipalities are not known at this time.

Unless the Province sets a standardized approach for this calculation, designated greenfield area densities calculated by municipalities across the GGH will not be comparable to each other due to the differences in takeouts. It is also possible that the municipalities that originally chose not to take out more land than was permitted under the Growth Plan may choose to do so in the next review of their official plan. If this occurs, a municipality might be able to justify a boundary expansion for additional land to accommodate growth, even though the growth forecasts may not have changed.


[1] Growth Plan, Section 2.2.7.3.
[2] The amount of land excluded can be considerable. For example, a study of the City of Brampton in Peel Region found that only about 50% of the total land area is used for employment and residential uses. Open space, utilities, and institutional uses make up the other half. Hemson Consulting Ltd., Assessment of Planned and Potential Growth in Designated Greenfield Areas, Discussion Paper for Public Review, City of Brampton, February 2009.